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Controversies About Indications for Transurethral Resection of the Prostate
0022-5347 /89/1413-D4 75$02.CO/O
Vol. 141, March Printed in U.S.A.
THE JOURNAL OF UROLOGY
Copyright© 1989 by The Williams & Vililkins Co.
Review Article CONTROVERSIES ABOUT INDICATIONS FOR TRANSURETHRAL RESECTION OF THE PROSTATE PEDER H. GRA VERSEN, THOMAS C. GASSER, JOHN H, WASSON, FRANK HINMAN, JR. REGINALD C. BRUSKEWITZ
AND
From the Urology Section, Veterans Administration Hospital and Department of Surgery, University of Wisconsin School of Medicine, Madison, Wisconsin, Department of Medicine, Veterans Administration Hospital and Regional Office Center, White River Junction, Vermont, and Division of Urology, University of California School of Medicine, San Francisco, California
Transurethral resection of the prostate was used initially to correct complete urinary obstruction due to benign prostatic hypertrophy. With its increased safety and availability, transurethral resection of the prostate currently is used primarily to alleviate less severe symptoms and signs of urinary outflow obstruction to improve quality of life. In 1983 urologists in the United States performed an estimated 357,000 transurethral prostatectomies, making it the tenth most frequent operation (fig. 1). 1 " The controversies about indications for prostatectorny, and some economic and political consequences of clinical uncertainty about its benefits and risks are reviewed. USUAL INDICATIONS FOR PROSTATECTOMY
Total outflow obstruction. The indication for prostatectomy for benign prostatic hypertrophy is clear and near absolute in any healthy elderly man who has acute retention, who cannot void satisfactorily after retention has been relieved and for whom a discrete precipitating cause, such as anticholinergic medication use or a recent operation, is not identified. Of 70 patients with acute retention and assumed benign prostatic hypertrophy treated initially with simple bladder drainage by catheterization 70 per cent had recurrent retention within 1 week and approximately 90 per cent required definitive treatment within 1 year.4 In another study of patients who had an episode of acute retention but who did not undergo immediate prostatectomy 57.5 per cent required an operation within the first 3 months." Although many patients with acute retention have had preceding symptoms of benign prostatic hypertrophy, the subjective and objective criteria of prostatism including prostate size do not appear to be good indicators of eventual urinary retention.6·' In an actuarial analysis of 123 patients with varying degrees of prostatism followed for 7 years about 10 per cent of the patients were expected to have acute retention." The unpredictability of acute retention implies a mechanism other than just culmination of the progression of benign prostatic hypertrophy: prostatic infarction was revealed histologically in 85 per cent of the patients operated on for acute retention but in only 3 per cent of those with benign prostatic hypertrophy without retention. 8 However, infarction may be a secondary event and most often a specific cause is not identified. Chronic outflow obstruction, post-void residual urine volume and azotemia. Chronic outflow obstruction with increasing volumes of residual urine may lead to overflow incontinence and eventually threaten life by embarrassment of renal function, particularly in a patient presenting with a urinary tract infection." Azotemia is a dreaded outcome of benign prostatic hypertrophy; azotemia was the single most significant finding influencing morbidity and mortality. 10 However, although up to 20 per cent of the patients undergoing transurethral resection 475
of the prostate may have elevated creatinine and/or blood urea nitrogen, milder grades of renal failure unrelated to benign prostatic hypertrophy are not uncommon in elderly people and the risk of azotemia developing in a man with prostatism is unclear. The observation of post-void residual urine commonly is taken as an indication of chronic obstruction. 11 A plain film after excretory urography (IVP) is inaccurate for determination of bladder volume and ultrasound is poor in quantitation of bladder volumes of less than 100 ml. but accurate for volumes greater than that amount. 12 • 11 Since some urologists may select patients for surgery on criteria of a residual urine level between 60 and 200 ml. or more, 11 · 14- 16 reliable measurements of volume by catheterization and the phenolsulfonphthalein test appear to be more appropriate when such specific criteria are used. However, setting such a volume cutoff is controversial in that other studies have shown that residual urine may originate from conditions other than outflow obstruction 17-' 9 and that severely obstructed patients may present with no post-void urine residual. Absence of residual urine is not proof that treatment can be postponed safely. 20 Moreover, residual urine volumes may vary widely in the same patient on repeated measurements and the volume does not correlate with the degree of obstruction as judged symptoms, urodynamic studies and cystoscopy. 19 A progressive increase in residual urine volumes with time may be observed in men with prostatism when subjected to annual residual urine determinations preoperatively (fig. 2). The duration of symptoms seems to correlate with residual urine volumeo 21 However, no positive correlation between preoperative residual urine volume and postoperative outcome has been observed. Urinary tract infection. Hasner showed that of 221 patients with prostatic obstruction who had no previous instrumentation and who had 50 ml. or more of residual urine 19 (8.6 per cent) presented with infection. 22 Of the 19 patients 9 had sev-ere obstruction with disordered renal function. Other studies of patients who underwent transurethral resection of the prostate suggest even higher rates of urinary tract infection but these patients often had catheter drainage for retention. 10 On the other hand, Bruskewitz and associates found no correlation between the amount of residual urine and history of urinary tract infection. 19 Thus, while elevated residual urine leading to infection seems to make sense, there is little evidence one way or the other to support the view that residual urine per se predisposes to urinary tract infection. Chronic bacterial prostatitis may be the most common cause of recurrent urinary tract infection in men. 2 " The prostate serves as a reservoir of bacteria between episodes of bladder bacteriuria. The troublesome medical treatment of the condi-
476
GRAVERSEN AND ASSOCIATES
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much asymptomatically as other patients without incontinence and all lost the urge incontinence by 1 year of followup. The symptoms of prostatism are not stable with time. A considerable proportion of patients may improve spontaneously.5'6''35-'39 Therefore, men with moderate or mild symptoms of prostatism are not necessarily predestined to have a gradual progression of symptoms. Unfortunately, neither the probability of spontaneous symptomatic change with time nor the development of retention can be predicted for the individual patient.
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tion may at times justify transurethral resection. Because the infection also is located in the peripheral prostate a thorough resection is especially important. Cure rates for infectious prostatitis range from 30 to 50 per cent after transurethral resection of the prostate 24 but the outcome of similar patients not undergoing transurethral resection of the prostate is not available for comparison. Prostate size. Estimation of prostatic size by digital palpation alone is an unreliable guide to determine anatomical size 25 ' 26 and prostatic size does not correlate with symptomatology18• 21 or postoperative outcome.2 7 However, if prostatic weight is estimated by cystoscopy along with simultaneous rectal examination it does correlate with the resected weight and with the preoperative obstructive symptoms. 26 - 28 Unless there is suggestion of significant obstruction the fact that a man has an enlarged prostate is not an indication for an operation. Indeed, many who benefit from transurethral resection of the prostate for significant obstruction have small prostates and postoperatively patients with small and large prostates fare equally well urodynamically and symptomatically. 27 However, there is an increased incidence of postoperative bladder neck contracture in patients with small prostates. 29 Analysis of symptoms. Symptoms of benign prostatic hypertrophy are obstructive (weak stream, abdominal straining, hesitancy, intermittency, incomplete bladder emptying and terminal dribbling) and irritative (frequency, nocturia and urgency); for comparison and analysis these symptoms can be graded by a symptom score scheme." 0 Only the symptoms of hesitancy and slow stream have been consistently correlated to urodynamic findings of obstruction." 1 Irritative symptoms are not statistically associated with obstruction but, rather, they may signify bladder instability 21 ·'n although this is not a consistent finding." 2 ·"3 There is disagreement as to the significance of severe irritative symptoms and whether these patients require urodynamic examination." 2 ,'34 In 1 study patients with mild or moderate preoperative urge incontinence improved as
SPECIAL EVALUATION METHODS
!VP. An IVP identifies incidental upper urinary tract pathological conditions but seldom influences the treatment of infravesical obstruction.4° The radiographic assessment ofprostatic size, bladder trabeculation, residual urine and presence of bladder stones is unreliable.41 However, for the evaluation of other entities, such as hematuria, the selective use of the IVP is indicated. The probability of finding significant disease in patients with prostatism alone does not appear to be greater than in the general population of similar age.4 2 Cystoscopy. Cystourethroscopy provides information about the configuration of the prostatic uret.hra and bladder. In addition, cystoscopy can identify obstructing urethral strictures and prostatic size can be reasonably estimated. Cystoscopic assessment of prostatic weight and length, and occlusion of the prostatic urethra correlate with the urodynamic parameters indicating infravesical obstruction. Andersen and Nordling concluded that symptom analysis, uroflowmetry and cystoscopy were sufficient to evaluate patients fully in whom the cystoscopic examination suggests obstruction. 28 Further urodynamic studies were recommended in patients with voiding symptoms and reduced flow rate but insignificant findings on cystourethroscopy. Trabeculation found at cystoscopy commonly is regarded as a sign of bladder hypertrophy secondary to long-standing infravesical obstruction. A study demonstrated that trabeculation correlated with detrusor opening pressure and with estimated prostatic weight at cystoscopy. 28 Severe trabeculation is accompanied by increased connective tissue infiltration of the detrusor muscle and is of importance in relation to bladder dysfunction. Cystoscopy by itself cannot be used to determine which patients should have surgical treatment and it cannot predict postoperative outcome largely because of the fact that some male patients with marked bladder outlet obstruction have endoscopically normal-appearing prostatic urethras, while other asymptomatic unobstructed male patients have enlarged prostates. Therefore, some urologists believe that cystoscopy need not be performed routinely to make the decision for prostatectomy but it may be done when the resectoscope is inserted at operation. Urodynamic studies. Whether urodynamic procedures should be performed to evaluate men with presumed benign prostatic hypertrophy is extremely controversial. 48 ' 44 The most useful flow variable in prostatism has been the maximum flow rate. Normal values have been defined statistically, and corrected for total volume voided, total bladder volume (volume voided plus residual) and patient age.4·5 - 47 Abrams and Griffiths showed that a maximum flow of less than 10 ml. per second in older men with prostatism usually correlated with additional urodynamic parameters suggesting infravesical obstruction. 17 ' 4 " They believed that a flow rate of less than 10 ml. with a sufficient voided volume and typical symptoms made further studies unnecessary. Patients with a maximum flow of 10 to 15 ml. per second may or may not be obstructed and should have further urodynamic investigations.4 8 Patients with higher flows in excess of 15 ml. per second generally are not obstructed, although 7 to 25 per cent of the patients with prostatism 49 ' 50 have higher
CONTROVERSIES ABOUT INDICATIONS FOR TRANSURETHRAL RESECTION OF PROSTATE
flow concomitant with benign prostatic hypertrophy and obstruction. However, a recent study found that the median maximum flow decreased from 18.5 ml. per second at a patient age of 50 years to 6.5 ml. per second at 80 years in asymptomatic elderly men." The conclusion was that the basis for evaluation of uroflowmetry should be normal values from age-matched controls. This would imply lower critical values. Abrams found that patients with higher preoperative flow rates had a lower success rate from prostatectomy and a tendency to more preoperative frequency and urgency.4 5 However, Iversen and associates found that patients with high flow and symptoms of prostatism, some of whom were unobstructed on further urodynamic evaluation, did as well as patients with lower flow when subjected to transurethral resection of the prostate. 50 Moreover, Jensen and associates, using statistical analysis and grouping patients with maximum flow of less than 10, 10 to 15 and greater than 15 ml. per second, were unable to identify a group of patients with less favorable outcome of surgery (that is patients with higher flow rates did as well as those with lower flow rates as judged by symptom score improvement).52 There was a trend towards a more favorable clinical outcome in patients with lower flows, although this finding lacked statistical significance. A pressure-flow study is performed when bladder pressure is measured via a urethral or suprapubic catheter during voiding. Urine flow is measured simultaneously. The most frequent recorded pressure-flow parameters are bladder opening pressure, maximum intravesical or detrusor pressure, and pressure at maximum flow. Other parameters are abdominal pressure and maximum voiding pressure. Voiding disorders caused by deficient relaxation of the external sphincter and pelvic floor can be determined simultaneously by electromyography. The pressure-flow relationship sometimes is used to calculate a urethral resistance factor as well. A committee of the International Continence Society identified 9 different formulas that have been used to characterize urethral resistance, all of which "originate from rigid tube hydrodynamics". 53 In that the urethra is far from rigid, this assumption may explain why the minimum urethral resistance factor generally has been of little predictive value. Elevated infravesical or detrusor opening pressure, elevated pressure at maximum flow and elevated minimum resistance have all been related to obstruction. However, none of them has been found useful to predict prospectively which patients would benefit from transurethral resection of the prostate. 54·"5 Measurement of static pressure in the urethral lumen yielding a urethral pressure profile with parameters, such as functional profile height, plateau height and prostatic plateau area, has been recommended for documentation of infravesical obstruction. 56 However, results may be difficult to reproduce and this method has little usefulness in the routine evaluation of patients with prostatism. In summary, although uroflowmetry is easy to perform and noninvasive, it cannot be used exclusively to diagnose infravesical obstruction nor predict less favorable surgical outcome. 57 • 58 It can be used as the first screening test and in a high percentage of patients uroflowmetry is useful to document outflow obstruction, although a low urine flow also may signify bladder decompensation. Pressure-flow studies and urethral pressure profiles, on the other hand, cannot as yet be recommended for the routine evaluation of patients who seem to have benign prostatic hypertrophy. Cystometry. The cystometrogram is used to study the bladder capacity, compliance and the presence of uninhibited contractions. The terms unstable, uninhibited or detrusor hyperreflexia have been applied when a patient cannot suppress an increase in intravesical pressure secondary to detrusor contractions. Uninhibited detrusor contractions have been defined as contractions exceeding 15 cm. water when the patient tries to suppress the contraction. Even pressure elevations of less than
477
15 cm. water may indicate uninhibited contractions but "clinical judgment should be exercised" in such cases. 53 Uninhibited bladder contractions often are associated with neurological disorders (for example multiple sclerosis, Parkinson's disease and after cerebrovascular accidents) and uninhibited detrusor contractions occur with increasing frequency with advancing patient age. The reported incidence of uninhibited detrusor contractions in healthy elderly men without symptomatic benign prostatic hypertrophy varies between 25 and 53 per cent. 59 • 60 Jones and Schoenberg reported uninhibited detrusor contractions in 11 per cent of elderly women, suggesting this as a baseline for uninhibited detrusor contractions in this age group. 61 The etiology of unstable contractions in benign prostatic hypertrophy is not clear. Increased vesical sensory input as well as a decreased cortical inhibition of the voiding reflex owing to age-related functional neurological changes have been suggested. 62 Chalfin and Bradley proposed a theory of increased sensory input: by injecting lidocaine into the lateral lobes of the prostate in patients with uninhibited detrusor contractions they eliminated the contraction in most patients. 63 Uninhibited contractions, which may explain the irritative symptoms in some patients with benign prostatic hypertrophy, are seen preoperatively in more than 50 per cent of the patients.21·33·58 However, correlation of uninhibited detrusor contractions with the degree of irritative symptoms is poor, 32 although a trend toward lower preoperative maximum flow rate, reduced total bladder capacity and increased age was noted in patients with postoperative uninhibited contractions. 33 Postprostatectomy uninhibited detrusor contractions are found in 20 to 30 per cent of the patients. 33·58·64 Several investigators have found that postoperative uninhibited contractions are associated with symptom treatment failure. 31 ·58·65·66 However, since only approximately 15 per cent of all patients undergoing transurethral resection of the prostate have a poor postoperative result32 ·58 a preoperative cystometrogram is not specific to identify patients who may not benefit from an operation. ECONOMIC AND POLITICAL IMPLICATIONS OF UNCERTAINTY ABOUT INDICATIONS FOR PROSTATECTOMY
The preceding discussion indicates that short of an extreme situation, such as azotemia or complete retention secondary to benign prostatic hypertrophy, indications for prostatectomy are difficult to define. The symptoms of prostatism are not pathognomonic of benign prostatic hypertrophy and the relative value of the clinical signs, physical findings, and endoscopic and urodynamic measurements is controversial. Urethral obstruction due to benign prostatic hypertrophy does not correlate strongly with any particular symptom, or physical, endoscopic or urodynamic finding. Since the indications for prostatectomy allow substantial room for disagreement, urologists should not be surprised that wide variations in the rate of prostatectomy exist: 67 an international comparison of prostatectomy rates in the 6 New England states in the United States, and England and Norway showed a mean age-standardized surgical rate per 100,000 population of 264, 132 and 236 respectively (that is men in New England were twice as likely to have undergone prostatectomy as were men in England). 68 In addition to the differences in average prostatectomy rates among countries, the amount of variation within 1 health care system is large in all countries studied, and unrelated to organization and financing of the medical care system. For example, in New England the prostatectomy rate at various locales ranged between roughly 180 and 420 per year per 100,000 men. The chance that male residents in Iowa who reach age 85 years have undergone prostatectomy range from 15 to more than 60 per cent in different hospital markets. 69 A survey of variations in small areas of medical care demonstrated that the rates for transurethral resection of the prostate varied as much as 4-fold. 70 Surgical procedures exhibiting the most variation often are for
478
GRAVERSEN AND ASSOCIATES
conditions that are part of the aging process, for example transurethral resection of the prostate for benign prostatic hypertrophy and hysterectomy for noncancerous diseases. 20, 6s, 10, n Since well defined scientific criteria that define the minimum symptomatology necessary for surgical treatment simply do not exist, the number of potential candidates for transurethral resection of the prostate is limited to some extent only by the size of the population. Consequently, the probability of being admitted to a hospital for treatment of suspected outflow obstruction can depend partly on the supply of physicians and hospitals in the region. 72 The population in the United States is aging and the number of senior citizens is increasing. In 1968 Lytton and associates reported that a 40-year-old man had a 10 per cent chance of undergoing prostatectomy during his lifetime. n A normative aging study in 1985 showed a 29 per cent probability. 74 A larger absolute number of men with prostatism due to benign prostatic hypertrophy explains part of the over-all increase in the number of transurethral prostatectomies performed but a substantial increase in the rate of surgery during the intervening years appears to be the main reason: the age-adjusted rate of transurethral resection of the prostate increased 150 per cent between 1968 and 1978. 73 ' 75 The varying probabilities that patients undergo transurethral resection of the prostate translates into strikingly varied costs in health and economic terms. In 1975 an estimated 3,421 patients in the United States died after transurethral resection of the prostate. 76 It was estimated-using actual rates for transurethral resection of the prostate and for postoperative mortality in Vermont and Maine-that under a low utilization rate 1,900 deaths would have occurred nationally, while a high rate of transurethral resection of the prostate would have meant 6,800 deaths as a direct consequence of prostatectomy. Likewise, the dollar expendit,ures for prostatectomy in 1975 could vary between $366 million and $1,195 million projected from low and high rates of utilization for transurethral resection of the prostate. 76 In 1983 an estimated 357,000 transurethral prostatectomies were conducted at an estimated cost of $4,200 per patient. This translates into a total expenditure of $1,499 million (fig. 3). This figure also depicts the projected differences in expenditures between the extreme examples of actual use of transurethral resection of the prostate in Vermont and Maine; if the surgery rates used in low rate regions of Vermont and Maine were the norm across the United States, the estimated expenditure would have been $0.81 billion, while the high utilization rate would have resulted in an estimated expenditure of $2.88 .
billion. However, fewer operations might mean more deaths among those who are not operated upon and higher dollar costs for nonoperative management of prostatism. Data by which to estimate these costs are not available. One of the first methods used by hospitals and their staffs in an attempt to regulate unwarranted procedures was through hospital tissue committees. These committees concentrated on reviewing all tissue removed and reported as histologically normal. Some studies have shown these committees to be effective in reducing the proportion of unjustified operations. 8 • 20 • 77 Yet, in the field of prostatectomy this does not appear to be the appropriate method to evaluate an operation. Benign prostatic hypertrophy is ubiquitous in the elderly male population, and the prostate size and, therefore, the amount of tissue removed neither reflect indications for nor predict the outcome of the procedure. The elective surgery second opinion program39• 78 is viewed as a means to contain health care costs but the review process has not influenced the patterns of variation substantially. After evaluation of a surgical second opinion program, Schachter and associates concluded that health care costs were not influenced substantially, since the programs could generate as much surgery as they avoided. 79 In the Federal Professional Standards Review Program, which is concerned with detecting examples of unnecessary services rendered by physicians, standards and guidelines have been developed. The standard attempts to identify unjustified treatments. 80 The goal of these programs is to ensure the making of some uniform professional decisions but it rests heavily on the presumption that an underlying professional consensus exists. On the contrary, the discretionary nature of evaluation of benign prostatic hypertrophy is suggested strongly by the 3 different sources of evidence discussed: variation in the rates of surgical procedures, 70 implications of second opinion programs 39 and a lack of consistency among surgeons evaluating identical clinical situations.81 Therefore, W ennberg and associates suggested a new public policy "away from its concentration on deviant professional behavior toward a policy of promoting improved and more uniform professional decision-making". 67 A plan combining feedback of information on the variation in community rates of use to physicians along with development of outcome studies was suggested. Information concerning outcome and variation in the use of operations has previously influenced the professional behavior of surgeons. 9 • 20 An example is tonsillectomy in Maine. 71 DISCUSSION
3000 2500 V, ~
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C
1500
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~
1000 500 0
A
... B
C
FIG. 3. Estimated total expenditures for transurethral prostatectomies in 1983 (B) compared to expenditures under low (A) and high (C) utilization rate.
Then, what is the appropriate use of transurethral resection of the prostate? A complete answer does not exist because we do not yet have the information to define precise indication for transurethral resection of the prostate: data, especially longterm followup data, concerning the outcome of transurethral resection of the prostate are incomplete, the risks and benefits of alternative therapies are poorly documented and quality of life after transurethral resection of the prostate or alternative therapies are most often not considered. For instance, are urinary function, sexual performance, activities of daily living (for example, sleep, mobility outside of home, social activities and work) and psychological well being (for example energy level and anxiety) better preserved or improved with one treatment than with another? It generally is accepted by urologists that transurethral resection of the prostate is a safe procedure with mortality rates of approximately 1 per cent; 10•14 most existing data are based on mortality within 30 days of procedure. However, 3 studies suggest that a longer followup is necessary to estimate the increased risk of death after prostatectomy. Sach and Marshall followed 477 consecutive patients subjected to prostatectomy (only 16 per cent were transurethral resections) and found that
INDIC"~.TI0l\T8 FOR TR.AJ"JSUR,ETHRAL RE8ECTI0~J OF' PROSTATE
4,2 c2nt vvere dead -within 3 months. 81 For n>lns»·.·,·Q 80 years or there was a 5-fold increase in mortality age-matched men as predicted from life tables. Another study demonstrated that within 1 year after transurethral resection of the prostate, patients had a considerably higher risk of death than agematched men;"' it was estimated that in a group of men 65 to 69 years old approximately 9 per cent would die within 1 year after prostatectomy compared to a predicted rate of 3.5 per cent in age-matched nonoperated men. In a recent report evaluating incidence of death and nonfatal complications after prostatectomy the over-all death rate within 91 days postoperatively was 3.7 per cent; most deaths occurred after the patient was discharged from the hospital. 82 Quantitation of the probability of various outcomes is necessary for the informed decision-making as well. For example, the incidence of impotence after prostatectomy is 4 to 40 per cent."''- 8 "· 84 In a recent study describing preoperative and postoperative sexual function 72 per cent of the patients were sexually active preoperatively and 31 per cent gave up their sexual activity postoperatively. Of the men still sexually active 49 per cent noticed retrograde ejaculation. 85 Since approximately half of the patients enrolled in the study were not completely followed these results must be interpreted carefully. The chance that a patient will require a subsequent urethral operation is important in deciding to perform prostatectomy. In 2 recent studies the 8-year cumulative rates of a second urethral or prostatic operation after transurethral resection of the prostate and open prostatectomy were 20.2 per cent and 16.8 per cent at a constant rate of 2.5 and 2 per cent per year, respectively .82 •86 Finally, it has been estimated that·the clinical diagnosis of obstructive benign prostatic hypertrophy is correct and prostatectomy is successful in approximately 85 per cent of the cases. However, the other 15 per cent translates into approximately 50,000 unnecessary or ineffective transurethral prostatectomies annually. Identification of even a portion of the unsuccessful treatments would result in considerable benefit. CONCLUSION
Most men with symptoms of benign prostatic hypertrophy are not predestined for obstructive uropathy or acute urinary retention. For most patients the decision whether to operate should be made by the patient after being fully informed. However, for patients to be truly informed we need additional information regarding the natural history of the disease, and we need clinical trials that provide more direct information on the outcomes of different treatments or treatment versus nontreatment. Postoperative mortality, morbidity and disability must be vv"'""'"'u against the complication rate of nontreatment and subsequent need for transurethral resection of the prostate in this control group. The of life must be assessed in the transurethral resection and control groups, When such information is available we will come closer to understanding the indications for prostatectomy in benign prostatic hypertrophy. A Veterans Administration Cooperative Study looking at these issues is underway. In addition, the analysis of epidemiological data can provide information on such things as surgical rate variation, mortality and re-treatment rates. When such population based data are combined with the results of improved clinical information about the risks and benefits of different evaluation and treatment strategies, urologists and their patients should be less uncertain about the proper course of action. REFERENCES l. Rutkow, I. M.: Urological operations in the United States: 1979 to 1984. J. Urol., 135: 1206, 1986. 2. Health-United States, 1982. United States Department of Health and Human Services, Publication No. (PHS) 83-1232. 3. Health-United States, 1985. United States Department of Health
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and Human 4. Breum, L., Klarskov, Munck, L. H. and Nordestgaard, A. G.: Significance of acute urinary retention due to intravesical obstruction. Scand. J. Urol. Nephrol., 16: 21, 1982, 5. Craigen, A. A., Hickling, J.B., Saunders, C.R. G. and Carpenter, R. G.: Natural history of prostatic obstruction. A prospective survey. J. Roy. Coll. Gen. Pract., 18: 226, 1969. 6. Birkhoff, J. D., Wiederhorn, A. R, Hamilton, M. L. and Zinsser, H. H.: Natural history of benign prostatic hypertrophy and acute urinary retention. Urology, 7: 48, 1976. 7. Powell, P. H., Smith, P. J. B. and Feneley, R. C. L.: The identification of patients at risk from acute retention. Brit. J. Urol., 52: 520, 1980. 8. Spiro, L. H., Labay, G. and Orkin, L. A.: Prostatic infarction: role in acute urinary retention. Urology, 3: 345, 1974. 9. Shortliffe, L. M. D. and Stamey, T. A.: Patients at risk of serious morbidity and/or renal scarring from recurrent bacteriuria. In: Campbell's Urology, 5th ed. Edited by P. C. Walsh, R. F. Gittes, A. D. Perlmutter and T. A. Stamey. Philadelphia: W. B. Saunders Co., vol. 1, sect. VII, chapt. 14, pp. 784-790, 1986. 10. Melchior, J., Valk, W. L., Foret, J. D. and Mebust, W. K.: Transurethral prostatectomy: computerized analysis of 2,223 consecutive cases. J. Urol., 112: 634, 1974. 11. Hinman, F., Jr.: Residual urine: measurement and influence on management of obstruction. In: Benign Prostatic Hypertrophy. Edited by F. Hinman, Jr. and 8. Boyarsky. New York: SpringerVerlag, Inc., chapt. 57, pp. 589-596, 1983. 12. Abrams, P. H., Farman, P., Lawrence, J. P. and Sherwood, T.: Residual urine in prostatism estimated by ultrasound scanning: a simple rule. Radiography, 49: 194, 1983. 13. Orgaz, R. E., Gomez, A. Z., Ramirez, C. T. and Torres, J. L. M.: Applications of bladder ultrasonography. I. Bladder content and residue. J. Urol., 125: 174, 1981. 14. Lund, B. L. and Dingsor, E.: Benign obstructive prostatic enlargement. A comparison between the results of treatment by transurethral electro-resection and the results of open surgery. Scand. J. Urol. Nephrol., 10: 33, 1976. 15. Smolev, J. K.: Bladder outlet obstruction. In: Principles of Ambulatory Medicine, 2nd ed. Edited by L. R. Barker, J. R. Burton and P. D. Zieve. Baltimore: The Williams & Wilkins Co., chapt. 48,pp. 568-573, 1986. 16. Whitmore, W. F., III: Benign prostatic hyperplasia: widespread and sometimes worrisome. Geriatrics, 36: 119, 1981. 17. Abrams, P. H. and Griffiths, D. J.: The assessment of prostatic obstruction from urodynamic measurements and from residual urine. Brit. J. Urol., 51: 129, 1979. 18. Castro, J.E., Griffiths, H.J. L. and Shackman, R.: Significance of signs and symptoms in benign prostatic hypertrophy. Brit. Med. J., 2: 598, 1969. 19. Bruskewitz, R. C., Iversen, P. and Madsen, P. 0.: Value ofpostvoid residual urine determination in evaluation of prostatism. Urology, 20: 602, 1982. 20. Dyck, F. J., Murphy, F. A., Murphy, J. K, Road, D. A., Boyd, M. S., Osborne, E., de Vlieger, D., Korchinski, B., Ripley, C., Bromley, A. T. and Innes, P. B.: Effect of surveillance on the number of hysterectomies in the province of Saskatchewan. New Engl. J. Med., 296: 1326, 1977. 21. Andersen, J. T., Nordling, J. and Walter, S.: Prostatism. I. The correlation between symptoms, cystometric and urodynamic findings. Scand. J. Uroi. Nephrol., 13: 229, 1979. 22. Hasner, E.: Prostatic urinary infection. Acta Chir. Scand., suppl. 285, p. 1, 1962. 23. Meares, E. M. and Stamey, T. A.: Bacteriologic localization patterns in bacterial prostatitis and urethritis. Invest. Urol., 5: 492, 1968. 24. Meares, E. M., Jr.: Prostatitis syndromes: new perspectives about old woes. J. Urol., 123: 141, 1980. 25. Meyhoff, H. H. and Hald, T.: Are doctors able to assess prostatic size? Scand. J. Urol. Nephrol., 12: 219, 1978. 26. Meyhoff, H. H., Ingemann, L., Nordling, J. and Hald, T.: Accuracy in preoperative estimation of prostatic size. A comparative evaluation of rectal palpation, intravenous pyelography, urethral closure pressure profile recording and cystourethroscopy. Sc and. J. Urol. Nephrol., 15: 45, 1981. 27. Jensen, K. M.-E., Bruskewitz, R. C., Iversen, P. and Madsen, P. 0.: Significance of prostatic weight in prostatism. Urol. Int., 38: 173, 1983.
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28. Andersen, J. T. and Nordling, J.: Prostatism. IL The correlation between cysto-urethroscopic, cystometric and urodynamic findings. Scand. J. Urol. Nephrol., 14: 23, 1980. 29. Bruskewitz, R. C., Larsen, E. H., Madsen, P. 0. and D0rflinger, T.: 3-Year followup of urinary symptoms after transurethral resection of the prostate. J. Urol., 136: 613, 1986. 30. Madsen, P. 0. and Iversen, P.: A point system for selecting operative candidates. In: Benign Prostatic Hypertrophy. Edited by F. Hinman, Jr. and S. Boyarsky. New York: Springer-Verlag, chapt. 79,pp. 763-765, 1983. 31. Abrams, P. H. and Feneley, R. C. L.: The significance of the symptoms associated with bladder outflow obstruction. Urol. Int., 33: 171, 1978. 32. Frimodt-M0ller, P. C., Jensen, K. M.-E., Iversen, P., Madsen, P. 0. and Bruskewitz, R.: Analysis of presenting symptoms in prostatism. J. Urol., 132: 272, 1984. 33. D0rflinger, T., Frimondt-M0ller, P. C., Bruskewitz, R. C., Jensen, K. M.-E., Iversen, P. and Madsen, P. 0.: The significance of uninhibited detrusor contractions in prostatism. J. Urol., 133: 819, 1985. 34. Blaivas, J. G.: Urodynamics: the second generation. J. Urol., 129: 783, 1983. 35. Jensen, K. M.-E. and Madsen, P. 0.: Candicidin treatment of prostatism: a prospective double-blind placebo-controlled study. Urol. Res., 11: 7, 1983. 36. Abrams, P.H.: A double-blind trial of the effects of Candicidin on patients with benign prostatic hypertrophy. Brit. J. Urol., 49: 67, 1977. 37. Ball, A. J., Feneley, R. C. L. and Abrams, P.H.: The natural history of untreated "prostatism". Brit. J. Urol., 53: 613, 1981. 38. Hedlund, H., Andersen, K.-E. and Ek, A.: Effects of prazosin in patients with benign prostatic obstruction. J. Urol., 130: 275, 1983. 39. Schlossberg, S. M., Finkel, M. L., Vaughan, E. D., Jr., Jensen, D., Riehle, R. A., Jr. and McCarthy, E. G.: Second opinion for urologic surgery. J. Urol., 131: 209, 1984. 40. Abrams, P. H.: Use of the intravenous urogram in diagnosis. In: Benign Prostatic Hypertrophy. Edited by F. Hinman, Jr. and S. Boyarsky. New York: Springer-Verlag, chapt. 60, pp. 605-609, 1983. 41. Andersen, J. T., Jacobsen, 0. and Standgaard, L.: The diagnostic value of intravenous pyelography in infravesical obstruction in males. Scand. J. Urol. Nephrol., 11: 225, 1977. 42. Bauer, D. L., Garrison, R. W. and McRoberts, J. W.: The health and cost implications of routine excretory urography before transurethral prostatectomy. J. Urol., 123: 386, 1980. 43. Gammelgaard, P.A., Andersen, J. T. and Meyhoff, H. H.: Clinical significance of urodynamic measurements. In: Benign Prostatic Hypertrophy. Edited by F. Hinman, Jr. and S. Boyarsky. New York: Springer-Verlag, chapt. 46, pp. 502-506, 1983. 44. Hinman, F., Jr.: Urodynamic testing: alternatives to electronics. J. Urol., 121: 643, 1979. 45. Abrams, P. H.: Prostatism and prostatectomy: the value of urine flow rate measurement in the preoperative assessment for operation. J. Urol., 117: 70, 1977. 46. Drach, G. W., Layton, T. and Bottaccini, M. R.: A method of adjustment of male peak urinary flow rate for varying age and volume voided. J. Urol., 128: 960, 1982. 47. Siroky, M. B., Olsson, C. A. and Krane, R. J.: The flow rate nomogram: I. Development. J. Urol., 122: 665, 1979. 48. Hald, T.: High-flow high-pressure obstruction. In: Benign Prostatic Hypertrophy. Edited by F. Hinman, Jr. and S. Boyarsky. New York: Springer-Verlag, chapt. 52, pp. 550-552, 1983. 49. Gerstenberg, T. C., Andersen, J. T., Klarskov, P., Ramirez, D. and Hald, T.: High flow infravesical obstruction in men: symptomatology, urodynamics and the results of surgery. J. Urol., 127: 943, 1982. 50. Iversen, P., Bruskewitz, R. C., Jensen, K. M.-E. and Madsen, P. 0.: Transurethral prostatic resection in the treatment of prostatism with high urinary flow. J. Urol., 129: 995, 1983. 51. J0rgensen, J. B., Jensen, K. M.-E., Bille-Brahe, N. E. and Morgensen, P.: Uroflowmetry in asymptomatic elderly males. Brit. J. Urol., 58: 390, 1986. 52. Jensen, K. M.-E., Bruskewitz, R. C., Iversen, P. and Madsen, P. 0.: Spontaneous uroflowmetry in prostatism. Urology, 24: 403, 1984. 53. Bates, P., Bradley, W. E., Glen, E., Griffiths, D., Melchior, H., Rowan, D., Sterling, A., Zinner, N. and Hald, T.: The standard-
54. 55. 56. 57.
58.
59. 60. 61.
62. 63. 64. 65. 66. 67. 68.
69. 70. 71. 72. 73. 74.
75.
76. 77. 78. 79.
ization of terminology of lower urinary tract function. J. Urol., 121: 551, 1979. Jensen, K. M.-E., Bruskewitz, R. C., Iversen, P. and Madsen, P. 0.: Predictive value of voiding pressures in benign prostatic hyperplasia. Neurourol. Urodynam., 2: 117, 1983. Bruskewitz, R., Jensen, K. M.-E., Iversen, P. and Madsen, P. 0.: The relevance of minimum urethral resistance in prostatism. J. Urol., 129: 769, 1983. Djurhuus, J. C., Nerstr0m, B., Mortensen, S., Hansen, R. I. and Rask-Andersen, H.: Urethral pressure profile in prostatic surgery. Urol. Int., 32: 146, 1977. Turner-Warwick, R., Whiteside, C. G., Arnold, E. P., Bates, C. P., Worth, P.H. L., Milroy, E.G. J., Webster, J. R. and Weir, J.: A urodynamic view of prostatic obstruction and the results of prostatectomy. Brit. J. Urol., 45: 631, 1973. Abrams, P. H., Farrar, D. J., Turner-Warwick, R. T., Whiteside, C. G. and Feneley, R. C. L.: The results of prostatectomy: a symptomatic and urodynamic analysis of 152 patients. J. Urol., 121: 640, 1979. Andersen, J. T., Jacobsen, 0., Worm-Petersen, J. and Hald, T.: Bladder function in healthy elderly males. Scand. J. Urol. Nephrol., 12: 123, 1978. Jensen, K. M.-E., Bruskewitz, R. C. and Madsen, P. 0.: Urodynamic findings in elderly males without pr,ostatic complaints. Urology, 24: 211, 1984. Jones, K. W. and Schoenberg, H. W.: Comparison of the incidence of bladder hyperreflexia in patients with benign prostatic hypertrophy and age-matched female controls. J. Urol., 133: 425, 1985. Andersen, J. T.: Detrusor hyperreflexia in benign infravesical obstruction. A cystometric study. J. Urol., 115: 532, 1976. Chalfin, S. A. and Bradley, W. E.: The etiology of detrusor hyperreflexia in patients with infravesical obstruction. J. Urol., 127: 938, 1982. Andersen, J. T.: Prostatism. Ill. Detrusor hyperreflexia and residual urine. Clinical and urodynamic aspects and the influence of surgery on the prostate. Scand. J. Urol. Nephrol., 16: 25, 1982. Cote, R. J., Burke, H. and Schoenberg, H. W.: Prediction of unusual postoperative results by urodynamic testing in benign prostatic hyperplasia. J. Urol., 125: 690, 1981. Abrams, P. H.: Investigation of postprostatectomy problems. Urology, 15: 209, 1980. Wennberg, J. E., Barnes, B. A. and Zubkoff, M.: Professional uncertainty and the problem of supplier-induced demand. Soc. Sci. Med., 16: 811, 1982. McPherson, K., Wennberg, J.E., Hovind, 0. B. and Clifford, P.: Small-area variations in the use of common surgical procedures: an international comparison of New England, England, and Norway. New Engl. J. Med., 307: 1310, 1982. Wennberg, J. E.: Dealing with medical practice variations: a proposal for action. Health Affairs, 3: 6, 1984. Wennberg, J. and Gittelsohn, A.: Variations in medical care among small areas. Sci. Amer., 246: 120, 1982. Wennberg, J. E., Blowers, L., Parker, R. and Gittelsohn, A.: Changes in tonsillectomy rates associated with feedback and review. Pediatrics, 59: 821, 1977. Lewis, C. E.: Variations in the incidence of surgery. New Engl. J. Med., 281: 880, 1969. Lytton, B., Emery, J. M. and Harvard, B. M.: The incidence of benign prostatic obstruction. J. Urol., 99: 639, 1968. Glynn, R. J., Campion, E.W., Bouchard, G. R. and Silbert, J.E.: The development of benign prostatic hyperplasia among volunteers in the Normative Aging Study. Amer. J. Epidemiol., 121: 78, 1985. Birkhoff, J. D.: Natural history of benign prostatic hypertrophy. In: Benign Prostatic Hypertrophy. Edited by F. Hinman, Jr. and S. Boyarsky. New York: Springer-Verlag, sect. I, chapt. 1, pp. 59, 1983. Wennberg, J. E., Bunker, J. P. and Barnes, J.: The need for assessing the outcome of common medical practices. Ann. Rev. Public Health, 1: 277, 1980. Weinert, H. V. and Brill, R.: Effectiveness of hospital tissue committee in raising surgical standards. J.A.M.A., 150: 992, 1952. Grafe, W. R., McSherry, C. K., Finkel, M. L. and McCarthy, E. G.: The elective surgery second opinion program. Ann. Surg., 188: 323, 1978. Schachter, M., Oppenheimer, G., Cannoodt, L. and Sieverts, S.: Evaluation of a surgical second opinion program. Qual. Rev.
CONTROVERSIES ABOUT INDICATIONS FOR TRANSURETHRAL RESECTION OF PROSTATE Bull., 9: 11, 1983. 80. Feldman, P. and Roberts, M.: Magic bullets or seven card stud: understanding health care regulation. In: Issues in Health Care Regulation. Edited by R. S. Gordon. New York: McGraw-Hill Book Co., pp. 66-109, 1980. 81. Sach, R. and Marshall, V. R.: Prostatectomy: its safety in an Australian teaching hospital. Brit. J. Surg., 64: 210, 1977. 82. Wennberg, J.E., Roos, M., Sola, L., Schori, A. and Jaffe, R.: Use of claims data systems to evaluate health care outcomes. Mortality and reoperation following prostatectomy. J.A.M.A., 257: 933, 1987.
481
83. Hargreave, T. B. and Stephenson, T. P.: Potency and prostatectomy. Brit. J. Urol., 49: 683, 1977. 84. Holtgrewe, H. L. and Valk, W. L.: Late results of transurethral prostatectomy. J. Urol., 92: 51, 1964. 85. M0ller-Nielsen, C., Lundhus, E., M0ller-Madsen, B., N0rgaard, J. P., Simonsen, 0. H., Hansen, S. L. and Birkler, N.: Sexual life following "minimal" and "total" transurethral prostatic resection. Urol. Int., 40: 3, 1985. 86. Roos, N. P. and Ramsey, E. W.: A population-based study of prostatectomy: outcomes associated with differing surgical approaches. J. Urol., 137: 1184, 1987.
Vol. 141, March Printed in U.S.A.
THE JOURNAL OF UROLOGY
Copyright© 1989 by The Williams & Vililkins Co.
Review Article CONTROVERSIES ABOUT INDICATIONS FOR TRANSURETHRAL RESECTION OF THE PROSTATE PEDER H. GRA VERSEN, THOMAS C. GASSER, JOHN H, WASSON, FRANK HINMAN, JR. REGINALD C. BRUSKEWITZ
AND
From the Urology Section, Veterans Administration Hospital and Department of Surgery, University of Wisconsin School of Medicine, Madison, Wisconsin, Department of Medicine, Veterans Administration Hospital and Regional Office Center, White River Junction, Vermont, and Division of Urology, University of California School of Medicine, San Francisco, California
Transurethral resection of the prostate was used initially to correct complete urinary obstruction due to benign prostatic hypertrophy. With its increased safety and availability, transurethral resection of the prostate currently is used primarily to alleviate less severe symptoms and signs of urinary outflow obstruction to improve quality of life. In 1983 urologists in the United States performed an estimated 357,000 transurethral prostatectomies, making it the tenth most frequent operation (fig. 1). 1 " The controversies about indications for prostatectorny, and some economic and political consequences of clinical uncertainty about its benefits and risks are reviewed. USUAL INDICATIONS FOR PROSTATECTOMY
Total outflow obstruction. The indication for prostatectomy for benign prostatic hypertrophy is clear and near absolute in any healthy elderly man who has acute retention, who cannot void satisfactorily after retention has been relieved and for whom a discrete precipitating cause, such as anticholinergic medication use or a recent operation, is not identified. Of 70 patients with acute retention and assumed benign prostatic hypertrophy treated initially with simple bladder drainage by catheterization 70 per cent had recurrent retention within 1 week and approximately 90 per cent required definitive treatment within 1 year.4 In another study of patients who had an episode of acute retention but who did not undergo immediate prostatectomy 57.5 per cent required an operation within the first 3 months." Although many patients with acute retention have had preceding symptoms of benign prostatic hypertrophy, the subjective and objective criteria of prostatism including prostate size do not appear to be good indicators of eventual urinary retention.6·' In an actuarial analysis of 123 patients with varying degrees of prostatism followed for 7 years about 10 per cent of the patients were expected to have acute retention." The unpredictability of acute retention implies a mechanism other than just culmination of the progression of benign prostatic hypertrophy: prostatic infarction was revealed histologically in 85 per cent of the patients operated on for acute retention but in only 3 per cent of those with benign prostatic hypertrophy without retention. 8 However, infarction may be a secondary event and most often a specific cause is not identified. Chronic outflow obstruction, post-void residual urine volume and azotemia. Chronic outflow obstruction with increasing volumes of residual urine may lead to overflow incontinence and eventually threaten life by embarrassment of renal function, particularly in a patient presenting with a urinary tract infection." Azotemia is a dreaded outcome of benign prostatic hypertrophy; azotemia was the single most significant finding influencing morbidity and mortality. 10 However, although up to 20 per cent of the patients undergoing transurethral resection 475
of the prostate may have elevated creatinine and/or blood urea nitrogen, milder grades of renal failure unrelated to benign prostatic hypertrophy are not uncommon in elderly people and the risk of azotemia developing in a man with prostatism is unclear. The observation of post-void residual urine commonly is taken as an indication of chronic obstruction. 11 A plain film after excretory urography (IVP) is inaccurate for determination of bladder volume and ultrasound is poor in quantitation of bladder volumes of less than 100 ml. but accurate for volumes greater than that amount. 12 • 11 Since some urologists may select patients for surgery on criteria of a residual urine level between 60 and 200 ml. or more, 11 · 14- 16 reliable measurements of volume by catheterization and the phenolsulfonphthalein test appear to be more appropriate when such specific criteria are used. However, setting such a volume cutoff is controversial in that other studies have shown that residual urine may originate from conditions other than outflow obstruction 17-' 9 and that severely obstructed patients may present with no post-void urine residual. Absence of residual urine is not proof that treatment can be postponed safely. 20 Moreover, residual urine volumes may vary widely in the same patient on repeated measurements and the volume does not correlate with the degree of obstruction as judged symptoms, urodynamic studies and cystoscopy. 19 A progressive increase in residual urine volumes with time may be observed in men with prostatism when subjected to annual residual urine determinations preoperatively (fig. 2). The duration of symptoms seems to correlate with residual urine volumeo 21 However, no positive correlation between preoperative residual urine volume and postoperative outcome has been observed. Urinary tract infection. Hasner showed that of 221 patients with prostatic obstruction who had no previous instrumentation and who had 50 ml. or more of residual urine 19 (8.6 per cent) presented with infection. 22 Of the 19 patients 9 had sev-ere obstruction with disordered renal function. Other studies of patients who underwent transurethral resection of the prostate suggest even higher rates of urinary tract infection but these patients often had catheter drainage for retention. 10 On the other hand, Bruskewitz and associates found no correlation between the amount of residual urine and history of urinary tract infection. 19 Thus, while elevated residual urine leading to infection seems to make sense, there is little evidence one way or the other to support the view that residual urine per se predisposes to urinary tract infection. Chronic bacterial prostatitis may be the most common cause of recurrent urinary tract infection in men. 2 " The prostate serves as a reservoir of bacteria between episodes of bladder bacteriuria. The troublesome medical treatment of the condi-
476
GRAVERSEN AND ASSOCIATES
400 0 0 0
c4
much asymptomatically as other patients without incontinence and all lost the urge incontinence by 1 year of followup. The symptoms of prostatism are not stable with time. A considerable proportion of patients may improve spontaneously.5'6''35-'39 Therefore, men with moderate or mild symptoms of prostatism are not necessarily predestined to have a gradual progression of symptoms. Unfortunately, neither the probability of spontaneous symptomatic change with time nor the development of retention can be predicted for the individual patient.
.Q
1i::,
a.
300
&3 0 0
X
--
Q ~2
.0
E ::,
z
.0
E ::,
z
0
1975
1979
1983
1975
Year
FIG. 1. Number of prostatectomies performed in United States 1· 3
160
E 120 Q)
C
·;::
=> 80 0 ::::,
-.::,
'iii
~ 40
10
9
8
7
6 5 4 Years Preop
3
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t Operated
FIG. 2. Mean residual urine volume in 57 patients recorded yearly before operation (adapted from data of Hinman) 11 •
tion may at times justify transurethral resection. Because the infection also is located in the peripheral prostate a thorough resection is especially important. Cure rates for infectious prostatitis range from 30 to 50 per cent after transurethral resection of the prostate 24 but the outcome of similar patients not undergoing transurethral resection of the prostate is not available for comparison. Prostate size. Estimation of prostatic size by digital palpation alone is an unreliable guide to determine anatomical size 25 ' 26 and prostatic size does not correlate with symptomatology18• 21 or postoperative outcome.2 7 However, if prostatic weight is estimated by cystoscopy along with simultaneous rectal examination it does correlate with the resected weight and with the preoperative obstructive symptoms. 26 - 28 Unless there is suggestion of significant obstruction the fact that a man has an enlarged prostate is not an indication for an operation. Indeed, many who benefit from transurethral resection of the prostate for significant obstruction have small prostates and postoperatively patients with small and large prostates fare equally well urodynamically and symptomatically. 27 However, there is an increased incidence of postoperative bladder neck contracture in patients with small prostates. 29 Analysis of symptoms. Symptoms of benign prostatic hypertrophy are obstructive (weak stream, abdominal straining, hesitancy, intermittency, incomplete bladder emptying and terminal dribbling) and irritative (frequency, nocturia and urgency); for comparison and analysis these symptoms can be graded by a symptom score scheme." 0 Only the symptoms of hesitancy and slow stream have been consistently correlated to urodynamic findings of obstruction." 1 Irritative symptoms are not statistically associated with obstruction but, rather, they may signify bladder instability 21 ·'n although this is not a consistent finding." 2 ·"3 There is disagreement as to the significance of severe irritative symptoms and whether these patients require urodynamic examination." 2 ,'34 In 1 study patients with mild or moderate preoperative urge incontinence improved as
SPECIAL EVALUATION METHODS
!VP. An IVP identifies incidental upper urinary tract pathological conditions but seldom influences the treatment of infravesical obstruction.4° The radiographic assessment ofprostatic size, bladder trabeculation, residual urine and presence of bladder stones is unreliable.41 However, for the evaluation of other entities, such as hematuria, the selective use of the IVP is indicated. The probability of finding significant disease in patients with prostatism alone does not appear to be greater than in the general population of similar age.4 2 Cystoscopy. Cystourethroscopy provides information about the configuration of the prostatic uret.hra and bladder. In addition, cystoscopy can identify obstructing urethral strictures and prostatic size can be reasonably estimated. Cystoscopic assessment of prostatic weight and length, and occlusion of the prostatic urethra correlate with the urodynamic parameters indicating infravesical obstruction. Andersen and Nordling concluded that symptom analysis, uroflowmetry and cystoscopy were sufficient to evaluate patients fully in whom the cystoscopic examination suggests obstruction. 28 Further urodynamic studies were recommended in patients with voiding symptoms and reduced flow rate but insignificant findings on cystourethroscopy. Trabeculation found at cystoscopy commonly is regarded as a sign of bladder hypertrophy secondary to long-standing infravesical obstruction. A study demonstrated that trabeculation correlated with detrusor opening pressure and with estimated prostatic weight at cystoscopy. 28 Severe trabeculation is accompanied by increased connective tissue infiltration of the detrusor muscle and is of importance in relation to bladder dysfunction. Cystoscopy by itself cannot be used to determine which patients should have surgical treatment and it cannot predict postoperative outcome largely because of the fact that some male patients with marked bladder outlet obstruction have endoscopically normal-appearing prostatic urethras, while other asymptomatic unobstructed male patients have enlarged prostates. Therefore, some urologists believe that cystoscopy need not be performed routinely to make the decision for prostatectomy but it may be done when the resectoscope is inserted at operation. Urodynamic studies. Whether urodynamic procedures should be performed to evaluate men with presumed benign prostatic hypertrophy is extremely controversial. 48 ' 44 The most useful flow variable in prostatism has been the maximum flow rate. Normal values have been defined statistically, and corrected for total volume voided, total bladder volume (volume voided plus residual) and patient age.4·5 - 47 Abrams and Griffiths showed that a maximum flow of less than 10 ml. per second in older men with prostatism usually correlated with additional urodynamic parameters suggesting infravesical obstruction. 17 ' 4 " They believed that a flow rate of less than 10 ml. with a sufficient voided volume and typical symptoms made further studies unnecessary. Patients with a maximum flow of 10 to 15 ml. per second may or may not be obstructed and should have further urodynamic investigations.4 8 Patients with higher flows in excess of 15 ml. per second generally are not obstructed, although 7 to 25 per cent of the patients with prostatism 49 ' 50 have higher
CONTROVERSIES ABOUT INDICATIONS FOR TRANSURETHRAL RESECTION OF PROSTATE
flow concomitant with benign prostatic hypertrophy and obstruction. However, a recent study found that the median maximum flow decreased from 18.5 ml. per second at a patient age of 50 years to 6.5 ml. per second at 80 years in asymptomatic elderly men." The conclusion was that the basis for evaluation of uroflowmetry should be normal values from age-matched controls. This would imply lower critical values. Abrams found that patients with higher preoperative flow rates had a lower success rate from prostatectomy and a tendency to more preoperative frequency and urgency.4 5 However, Iversen and associates found that patients with high flow and symptoms of prostatism, some of whom were unobstructed on further urodynamic evaluation, did as well as patients with lower flow when subjected to transurethral resection of the prostate. 50 Moreover, Jensen and associates, using statistical analysis and grouping patients with maximum flow of less than 10, 10 to 15 and greater than 15 ml. per second, were unable to identify a group of patients with less favorable outcome of surgery (that is patients with higher flow rates did as well as those with lower flow rates as judged by symptom score improvement).52 There was a trend towards a more favorable clinical outcome in patients with lower flows, although this finding lacked statistical significance. A pressure-flow study is performed when bladder pressure is measured via a urethral or suprapubic catheter during voiding. Urine flow is measured simultaneously. The most frequent recorded pressure-flow parameters are bladder opening pressure, maximum intravesical or detrusor pressure, and pressure at maximum flow. Other parameters are abdominal pressure and maximum voiding pressure. Voiding disorders caused by deficient relaxation of the external sphincter and pelvic floor can be determined simultaneously by electromyography. The pressure-flow relationship sometimes is used to calculate a urethral resistance factor as well. A committee of the International Continence Society identified 9 different formulas that have been used to characterize urethral resistance, all of which "originate from rigid tube hydrodynamics". 53 In that the urethra is far from rigid, this assumption may explain why the minimum urethral resistance factor generally has been of little predictive value. Elevated infravesical or detrusor opening pressure, elevated pressure at maximum flow and elevated minimum resistance have all been related to obstruction. However, none of them has been found useful to predict prospectively which patients would benefit from transurethral resection of the prostate. 54·"5 Measurement of static pressure in the urethral lumen yielding a urethral pressure profile with parameters, such as functional profile height, plateau height and prostatic plateau area, has been recommended for documentation of infravesical obstruction. 56 However, results may be difficult to reproduce and this method has little usefulness in the routine evaluation of patients with prostatism. In summary, although uroflowmetry is easy to perform and noninvasive, it cannot be used exclusively to diagnose infravesical obstruction nor predict less favorable surgical outcome. 57 • 58 It can be used as the first screening test and in a high percentage of patients uroflowmetry is useful to document outflow obstruction, although a low urine flow also may signify bladder decompensation. Pressure-flow studies and urethral pressure profiles, on the other hand, cannot as yet be recommended for the routine evaluation of patients who seem to have benign prostatic hypertrophy. Cystometry. The cystometrogram is used to study the bladder capacity, compliance and the presence of uninhibited contractions. The terms unstable, uninhibited or detrusor hyperreflexia have been applied when a patient cannot suppress an increase in intravesical pressure secondary to detrusor contractions. Uninhibited detrusor contractions have been defined as contractions exceeding 15 cm. water when the patient tries to suppress the contraction. Even pressure elevations of less than
477
15 cm. water may indicate uninhibited contractions but "clinical judgment should be exercised" in such cases. 53 Uninhibited bladder contractions often are associated with neurological disorders (for example multiple sclerosis, Parkinson's disease and after cerebrovascular accidents) and uninhibited detrusor contractions occur with increasing frequency with advancing patient age. The reported incidence of uninhibited detrusor contractions in healthy elderly men without symptomatic benign prostatic hypertrophy varies between 25 and 53 per cent. 59 • 60 Jones and Schoenberg reported uninhibited detrusor contractions in 11 per cent of elderly women, suggesting this as a baseline for uninhibited detrusor contractions in this age group. 61 The etiology of unstable contractions in benign prostatic hypertrophy is not clear. Increased vesical sensory input as well as a decreased cortical inhibition of the voiding reflex owing to age-related functional neurological changes have been suggested. 62 Chalfin and Bradley proposed a theory of increased sensory input: by injecting lidocaine into the lateral lobes of the prostate in patients with uninhibited detrusor contractions they eliminated the contraction in most patients. 63 Uninhibited contractions, which may explain the irritative symptoms in some patients with benign prostatic hypertrophy, are seen preoperatively in more than 50 per cent of the patients.21·33·58 However, correlation of uninhibited detrusor contractions with the degree of irritative symptoms is poor, 32 although a trend toward lower preoperative maximum flow rate, reduced total bladder capacity and increased age was noted in patients with postoperative uninhibited contractions. 33 Postprostatectomy uninhibited detrusor contractions are found in 20 to 30 per cent of the patients. 33·58·64 Several investigators have found that postoperative uninhibited contractions are associated with symptom treatment failure. 31 ·58·65·66 However, since only approximately 15 per cent of all patients undergoing transurethral resection of the prostate have a poor postoperative result32 ·58 a preoperative cystometrogram is not specific to identify patients who may not benefit from an operation. ECONOMIC AND POLITICAL IMPLICATIONS OF UNCERTAINTY ABOUT INDICATIONS FOR PROSTATECTOMY
The preceding discussion indicates that short of an extreme situation, such as azotemia or complete retention secondary to benign prostatic hypertrophy, indications for prostatectomy are difficult to define. The symptoms of prostatism are not pathognomonic of benign prostatic hypertrophy and the relative value of the clinical signs, physical findings, and endoscopic and urodynamic measurements is controversial. Urethral obstruction due to benign prostatic hypertrophy does not correlate strongly with any particular symptom, or physical, endoscopic or urodynamic finding. Since the indications for prostatectomy allow substantial room for disagreement, urologists should not be surprised that wide variations in the rate of prostatectomy exist: 67 an international comparison of prostatectomy rates in the 6 New England states in the United States, and England and Norway showed a mean age-standardized surgical rate per 100,000 population of 264, 132 and 236 respectively (that is men in New England were twice as likely to have undergone prostatectomy as were men in England). 68 In addition to the differences in average prostatectomy rates among countries, the amount of variation within 1 health care system is large in all countries studied, and unrelated to organization and financing of the medical care system. For example, in New England the prostatectomy rate at various locales ranged between roughly 180 and 420 per year per 100,000 men. The chance that male residents in Iowa who reach age 85 years have undergone prostatectomy range from 15 to more than 60 per cent in different hospital markets. 69 A survey of variations in small areas of medical care demonstrated that the rates for transurethral resection of the prostate varied as much as 4-fold. 70 Surgical procedures exhibiting the most variation often are for
478
GRAVERSEN AND ASSOCIATES
conditions that are part of the aging process, for example transurethral resection of the prostate for benign prostatic hypertrophy and hysterectomy for noncancerous diseases. 20, 6s, 10, n Since well defined scientific criteria that define the minimum symptomatology necessary for surgical treatment simply do not exist, the number of potential candidates for transurethral resection of the prostate is limited to some extent only by the size of the population. Consequently, the probability of being admitted to a hospital for treatment of suspected outflow obstruction can depend partly on the supply of physicians and hospitals in the region. 72 The population in the United States is aging and the number of senior citizens is increasing. In 1968 Lytton and associates reported that a 40-year-old man had a 10 per cent chance of undergoing prostatectomy during his lifetime. n A normative aging study in 1985 showed a 29 per cent probability. 74 A larger absolute number of men with prostatism due to benign prostatic hypertrophy explains part of the over-all increase in the number of transurethral prostatectomies performed but a substantial increase in the rate of surgery during the intervening years appears to be the main reason: the age-adjusted rate of transurethral resection of the prostate increased 150 per cent between 1968 and 1978. 73 ' 75 The varying probabilities that patients undergo transurethral resection of the prostate translates into strikingly varied costs in health and economic terms. In 1975 an estimated 3,421 patients in the United States died after transurethral resection of the prostate. 76 It was estimated-using actual rates for transurethral resection of the prostate and for postoperative mortality in Vermont and Maine-that under a low utilization rate 1,900 deaths would have occurred nationally, while a high rate of transurethral resection of the prostate would have meant 6,800 deaths as a direct consequence of prostatectomy. Likewise, the dollar expendit,ures for prostatectomy in 1975 could vary between $366 million and $1,195 million projected from low and high rates of utilization for transurethral resection of the prostate. 76 In 1983 an estimated 357,000 transurethral prostatectomies were conducted at an estimated cost of $4,200 per patient. This translates into a total expenditure of $1,499 million (fig. 3). This figure also depicts the projected differences in expenditures between the extreme examples of actual use of transurethral resection of the prostate in Vermont and Maine; if the surgery rates used in low rate regions of Vermont and Maine were the norm across the United States, the estimated expenditure would have been $0.81 billion, while the high utilization rate would have resulted in an estimated expenditure of $2.88 .
billion. However, fewer operations might mean more deaths among those who are not operated upon and higher dollar costs for nonoperative management of prostatism. Data by which to estimate these costs are not available. One of the first methods used by hospitals and their staffs in an attempt to regulate unwarranted procedures was through hospital tissue committees. These committees concentrated on reviewing all tissue removed and reported as histologically normal. Some studies have shown these committees to be effective in reducing the proportion of unjustified operations. 8 • 20 • 77 Yet, in the field of prostatectomy this does not appear to be the appropriate method to evaluate an operation. Benign prostatic hypertrophy is ubiquitous in the elderly male population, and the prostate size and, therefore, the amount of tissue removed neither reflect indications for nor predict the outcome of the procedure. The elective surgery second opinion program39• 78 is viewed as a means to contain health care costs but the review process has not influenced the patterns of variation substantially. After evaluation of a surgical second opinion program, Schachter and associates concluded that health care costs were not influenced substantially, since the programs could generate as much surgery as they avoided. 79 In the Federal Professional Standards Review Program, which is concerned with detecting examples of unnecessary services rendered by physicians, standards and guidelines have been developed. The standard attempts to identify unjustified treatments. 80 The goal of these programs is to ensure the making of some uniform professional decisions but it rests heavily on the presumption that an underlying professional consensus exists. On the contrary, the discretionary nature of evaluation of benign prostatic hypertrophy is suggested strongly by the 3 different sources of evidence discussed: variation in the rates of surgical procedures, 70 implications of second opinion programs 39 and a lack of consistency among surgeons evaluating identical clinical situations.81 Therefore, W ennberg and associates suggested a new public policy "away from its concentration on deviant professional behavior toward a policy of promoting improved and more uniform professional decision-making". 67 A plan combining feedback of information on the variation in community rates of use to physicians along with development of outcome studies was suggested. Information concerning outcome and variation in the use of operations has previously influenced the professional behavior of surgeons. 9 • 20 An example is tonsillectomy in Maine. 71 DISCUSSION
3000 2500 V, ~
a 2000 0
0
C
1500
0
~
1000 500 0
A
... B
C
FIG. 3. Estimated total expenditures for transurethral prostatectomies in 1983 (B) compared to expenditures under low (A) and high (C) utilization rate.
Then, what is the appropriate use of transurethral resection of the prostate? A complete answer does not exist because we do not yet have the information to define precise indication for transurethral resection of the prostate: data, especially longterm followup data, concerning the outcome of transurethral resection of the prostate are incomplete, the risks and benefits of alternative therapies are poorly documented and quality of life after transurethral resection of the prostate or alternative therapies are most often not considered. For instance, are urinary function, sexual performance, activities of daily living (for example, sleep, mobility outside of home, social activities and work) and psychological well being (for example energy level and anxiety) better preserved or improved with one treatment than with another? It generally is accepted by urologists that transurethral resection of the prostate is a safe procedure with mortality rates of approximately 1 per cent; 10•14 most existing data are based on mortality within 30 days of procedure. However, 3 studies suggest that a longer followup is necessary to estimate the increased risk of death after prostatectomy. Sach and Marshall followed 477 consecutive patients subjected to prostatectomy (only 16 per cent were transurethral resections) and found that
INDIC"~.TI0l\T8 FOR TR.AJ"JSUR,ETHRAL RE8ECTI0~J OF' PROSTATE
4,2 c2nt vvere dead -within 3 months. 81 For n>lns»·.·,·Q 80 years or there was a 5-fold increase in mortality age-matched men as predicted from life tables. Another study demonstrated that within 1 year after transurethral resection of the prostate, patients had a considerably higher risk of death than agematched men;"' it was estimated that in a group of men 65 to 69 years old approximately 9 per cent would die within 1 year after prostatectomy compared to a predicted rate of 3.5 per cent in age-matched nonoperated men. In a recent report evaluating incidence of death and nonfatal complications after prostatectomy the over-all death rate within 91 days postoperatively was 3.7 per cent; most deaths occurred after the patient was discharged from the hospital. 82 Quantitation of the probability of various outcomes is necessary for the informed decision-making as well. For example, the incidence of impotence after prostatectomy is 4 to 40 per cent."''- 8 "· 84 In a recent study describing preoperative and postoperative sexual function 72 per cent of the patients were sexually active preoperatively and 31 per cent gave up their sexual activity postoperatively. Of the men still sexually active 49 per cent noticed retrograde ejaculation. 85 Since approximately half of the patients enrolled in the study were not completely followed these results must be interpreted carefully. The chance that a patient will require a subsequent urethral operation is important in deciding to perform prostatectomy. In 2 recent studies the 8-year cumulative rates of a second urethral or prostatic operation after transurethral resection of the prostate and open prostatectomy were 20.2 per cent and 16.8 per cent at a constant rate of 2.5 and 2 per cent per year, respectively .82 •86 Finally, it has been estimated that·the clinical diagnosis of obstructive benign prostatic hypertrophy is correct and prostatectomy is successful in approximately 85 per cent of the cases. However, the other 15 per cent translates into approximately 50,000 unnecessary or ineffective transurethral prostatectomies annually. Identification of even a portion of the unsuccessful treatments would result in considerable benefit. CONCLUSION
Most men with symptoms of benign prostatic hypertrophy are not predestined for obstructive uropathy or acute urinary retention. For most patients the decision whether to operate should be made by the patient after being fully informed. However, for patients to be truly informed we need additional information regarding the natural history of the disease, and we need clinical trials that provide more direct information on the outcomes of different treatments or treatment versus nontreatment. Postoperative mortality, morbidity and disability must be vv"'""'"'u against the complication rate of nontreatment and subsequent need for transurethral resection of the prostate in this control group. The of life must be assessed in the transurethral resection and control groups, When such information is available we will come closer to understanding the indications for prostatectomy in benign prostatic hypertrophy. A Veterans Administration Cooperative Study looking at these issues is underway. In addition, the analysis of epidemiological data can provide information on such things as surgical rate variation, mortality and re-treatment rates. When such population based data are combined with the results of improved clinical information about the risks and benefits of different evaluation and treatment strategies, urologists and their patients should be less uncertain about the proper course of action. REFERENCES l. Rutkow, I. M.: Urological operations in the United States: 1979 to 1984. J. Urol., 135: 1206, 1986. 2. Health-United States, 1982. United States Department of Health and Human Services, Publication No. (PHS) 83-1232. 3. Health-United States, 1985. United States Department of Health
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