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Computed tomography in diagnosis of pelvic lipomatosis
COMPUTED PELVIC DANIEL EDWIN
TOMOGRAPHY
IN DIAGNOSIS
OF
LIPOMATOSIS E. SUSMANO, H. DOLIN,
M.D.
M.D.
From the Departments of Surgery (Urology) Mercy Center for Health Care Services, Aurora, Illinois
and Radiology,
ABSTRACT - Pelvic lipomatosis is a disease characterized by abnormal deposition of mature adipose tissue within the confines of the pelvis surrounding the bladder, prostate, and rectosigmoid. The presenting symptoms are vague and nonspecijc, and it has typical radiologic features. Computed tomography is extremely useful in the di&ferential diagnosis because of its ability to differentiate fatty infiltration from other conditions which can cause elevation and compression of the urinary bladder and sigmoid colon. Computed tomographic confirmation of the presence of fat surrounding the bladder and rectum eliminates the need for surgical biopsy, unless indicated fw other reasons. The course of this disease is usually benign and indolent, however a close follow-up is mandatory to rule out those cases in which ureteral obstruction may develop requiring surgical relief of the obstruction. When cystitis glandularis is found in association with pelvic lipomatosis, periodic cystoscopic examinations are recommended because of the potential risk of malignant transformation.
Pelvic lipomatosis is a term coined by Fogg and Smyth in 1968l to describe an entity first reported by Engels in 195g2 and characterized by an overgrowth of normal fatty tissue limited to the perirectal and perivesical spaces in the pelvis. There is increased awareness of this disease as more cases are being reported in the lithowever it is likely that pelvic erature, lipomatosis is a more common disease than has been reported to date. Typical radiologic features of tear-shaped deformity of the bladder, increased radiolucency of the pelvic soft tissues, and elevation of the bladder and rectosigmoid outside the pelvis led some authors to believe that pelvic lipomatosis has pathognomonic radiologic findings which when present eliminate the need for surgical biopsy.3-5 To the contrary, others believe that tissue diagnosis is mandatory and that negative findings at biopsy should not be looked upon as unnecessary surgery.6-8 This article reports 3 cases of pelvic lipomatosis which we have had the opportunity to study with computed tomography (CT)
UROLOGY
/ FEBRUARY
1979 / VOLUME
XIII,
NUMBER
which we believe has a definite role in the diagnosis of this pathologic entity. All CT scans were performed on an EMI CT 5005 total body scanner. Scan time per slice was twenty seconds. Contrast enhancement scans were obtained after the intravenous infusion of 300 cc. of contrast material (Reno-M-Dip). Case Reports Case 1 This fifty-year-old black man (height 6 feet 3 inches, weight 245 pounds) was admitted because of persistent pain in the right lower abdominal quadrant and right inguinal pain. No gastrointestinal or genitourinary symptoms were present, and physical examination was unremarkable. Laboratory data were within normal limits except for a slight elevation of the serum alkaline phosphatase level. Upper gastrointestinal and gallbladder x-ray films were normal. Barium enema showed a fusiform appearance with elongation of the rectosigmoid (Fig. 1A). An
2
215
FIGURE 1. Case 1 (A) Barium enema showing fusiform appearance with elongation of rectosigmoid. (B) IVP showing mild bilateral ureteral dilatation, deformity of the bladder, and increased radiolucency of tissue surrounding bladder. (C) Computed tomography: bladder and rectum symmetrically surrounded by low density tissue with same absorption value as subcutaneous fat.
A intravenous pyelogram (IVP) showed mild bilateral ureteral dilatation with marked elevation of the floor of the bladder which also appeared to be displaced anteriorly (Fig. 1B). Cystoscopic examination was difficult to perform because of the marked elevation of the floor of the bladder and elongation of the prostatic urethra. The instrument barely entered the bladder. Minimal changes of cystitis cystica were noted. Exploratory surgery was performed on August 4, 1975. A tremendous proliferation of normalappearing fatty tissue was encountered intimately attached to the pelvic bone and completely surrounding the bladder and rectum.
Multiple biopsy specimens were taken. The peritoneum and bladder were entered during the dissection. It was considered impossible to remove completely all the fatty tissue. He had an uneventful postoperative course. Findings on IVP in December, 1975, were unchanged. The patient was readmitted to the hospital in March, 1977, because of recurrent pain in the right lower abdominal quadrant. IVP showed no progressive hydronephronic changes. Renal function remained normal. On computed tomography the bladder and rectum were symmetrically surrounded by low density tissue with the same absorption value as subcutaneous
FIGURE 2. Case 2. (A) IVP showing mild bilateral ureteral dilatation, deformity of bladder, and marked elevation of floor of bladder. (B) Barium enema showing typical deformity of rectosigmoid which appeared elevated out of pelvis. (C) Computed tomography showing similar findings to Case 1.
216
UROLOGY
/ FEBRUARY
1979 / VOLUME XIII, NUMBER 2
FIGURE 3. Case 3. (A) IVP showing normal upper tracts and deformity of bladder with elevation of floor of bladder. (B) Computed tomography again shows bladder and rectum surrounded by increased amount of low density tissue with same absorption value as subcutaneous fat.
fat (Fig. 1C). Absorption values ranged from -18 EM1 units to -70 EM1 units with a mean density of -40 EM1 units. Normal tissue planes were preserved. Case 2
The patient (height 5 feet 6 inches, weight 155 pounds) was first admitted to the hospital at age thirty-seven years. This was in July, 1974, because of suprapubic discomfort, occasional burning on urination, and terminal hematuria. IVP showed deformity of the bladder with elevation of the floor of the bladder and normal upper tracts (Fig. 2A). Cystoscopy revealed several papillary growths involving the bladder neck, trigone, and posterior urethra. Multiple biopsy specimens were taken and reported as cystitis glandularis. Cystogram showed a tearshaped bladder. Cystoscopic examination since then with biopsies of the involved areas revealed no changes in the histologic appearance of the lesion. Repeat IVP in March, 1976, showed no change in comparison with the IVP obtained in 1974. Barium enema demonstrated typical deformity of the rectosigmoid which appeared elevated out of the pelvis (Fig. 2B). Findings on computed tomography were similar to those in Case 1 (Fig. 2C). Case 3
This forty-four-year-old white man (height 6 feet 4 inches, weight 240 pounds) had a twoyear history of hypertension. A timed IVP showed slight differential dye excretion of the contrast material through both kidneys, also an oval-shaped configuration of the bladder with elevation of the floor of the bladder (Fig. 3A). There were no urinary tract symptoms. A workup for hypertension including an arteriogram
UROLOGY
/
FEBRUARY
1979 / VOLUME XIII, NUMBER 2
was negative. Cystogram showed a tear-shaped bladder with elevation of the floor of the bladder suggestive of pelvic lipomatosis. A barium enema revealed narrowing and elongation of the rectosigmoid caused by a radiolucent pelvic mass. Findings on computed tomography were similar to those in Case 1 (Fig. 3B). There was no evidence of lymphadenopathy, hematoma, or other condition which may simulate pelvic lipomatosis. Cystoscopy revealed minimal changes of cystitis cystica. Follow-up IVP six months later showed no change in the appearance of the bladder with no ureteral dilatation. The patient remained asymptomatic. The blood pressure has remained under control with triamterene and hydrochlorothiazide (Dyazide) and methyldopa (Aldomet). Comment The cause of pelvic lipomatosis remains uncertain, although several different opinions have been expressed. Engels suggested that pelvic lipomatosis resulted from chronic lower urinary tract infection. There had been, however, numerous cases of patients with no urinary symptoms and negative findings on urinalysis. Others have considered it to be a localized form of obesity. If this were the case, however, one would expect to encounter this abnormality fi-equently.g Rosenberg, Hurwitz, and Hermann’O suggested that pelvic lipomatosis may represent a variant of Dercum disease with retroperitoneal and perivesical fatty infiltration. Pelvic lipomatosis occurs predominantly in men, those between the ages of twenty-five to forty years being the most commonly affected. Only 3 cases have been reported in womenll and a single pediatric casee3 In those cases in which surgical exploration was performed, the bladder, prostate, and rectum have been found
217
to be enveloped but not invaded by dense, vascular, nonencapsulated lipomatous tissue. This fibrolipomatous tissue will occasionally extend outside of the pelvis into the retroperitoneal area surrounding the ureters and vena cava.12 The histologic findings have been of mature adipose tissue or with variable amount of fibrous matrix and chronic inflammatory cells. The nonencapsulation differentiates this condition from a true lipoma. The symptoms of patients with pelvic lipomatosis are nonspecific. Some present with genitourinary symptoms, frequency, dysuria, and difficulty starting urination. l-3,13 Gastrointestinal symptoms occur less frequently and may present as mild constipation. A significant number of cases have been diagnosed at evaluation for unrelated problems, especially hypertension. 3,5~14The significance of the apparent relation of hypertension to pelvic lipomatosis is not clear and may be a fortuitous occurrence. The physical findings also are often nonspecific. Mild obesity may be present. Abdominal examination may reveal a vague suprapubic mass. On rectal examination the prostate is characteristically found high in position owing to elevation from the fatty tissue. A pelvic mass representing the adipose tissue can be palpated on rectal examination. Because of elevation of the bladder base and deformity of the sigmoid colon, performance of sigmoidoscopy and cystoscopy are characteristically difficult. Laboratory tests usually reveal normal renal, liver, and endocrine function. The radiologic manifestations are more characteristic including: (1) increased radiolucency of the soft tissues of the pelvis which is due to the low radiographic density of the excess fat that surrounds the bladder and the rectum; (2) elevation out of the pelvis of the urinary bladder which often is teardrop or gourd in configuration; (3) elongation and narrowing of the rectosigmoid with an intact colonic mucosa. The intravenous pyelogram often reveals medial deviation of the distal ureters and mild to sometimes severe dilatation and lateral displacement of the mid and upper ureters. Sigmoidoscopy when it has been performed has confirmed the straightening of the colon and absence of intrinsic lesions. Cystoscopic examination has been difficult to perform because of marked elongation of the prostatic urethra. When successful, it has revealed the frequent association of various forms of proliferative cystitis with pelvic lipomatosis.14 Cystitis follicularis, cystitis cystica, and cystitis glandularis
218
have been found and confirmed by histologic examination. These various forms of proliferative cystitis are known to develop in the presence of chronic irritation due to infection or obstruction. Whether a chronic inflammatory reaction leads to the development of the proliferative cystitis and the pelvic lipomatosis or whether pelvic lipomatosis somehow is responsible for initiating the glandular metaplasia is still debatable. Adenocarcinoma of the bladder has been reported to arise from cystitis glandularis.15 There have been no reports, however, of this complication in association with pelvic lipomatosis, but the assumption should probably be made that cystitis glandularis in any setting is a premalignant condition.8 All our patients had a cystoscopic examination. In Case 1 it was technically difficult to perform, but minor changes of cystitis cystica were encountered as in Case 3. Case 2 presented with hematuria. Cystoscopy revealed severe vesical changes of cystitis glandularis which had been confirmed with multiple biopsies since he was first seen in 1974. Schechter in 197412 reported a case of pelvic lipomatosis associated with inferior vena caval and external iliac vein obstruction which on surgical exploration revealed a large amount of fibrous fatty tissue around the bladder and the inferior vena cava, also causing extrinsic pressure defects on the pelvic veins which he believed was the cause of the venous obstruction. Also in 1974 Abbott and Skinner’ reported a case in which complete occlusion of the inferior vena cava in association with pelvic lipomatosis was encountered. They believed that the obstruction of the inferior vena cava was of congenital origin. They also pointed out the high incidence of postoperative thrombophlebitis noted in these patients and the remarkable vascularity associated with this fatty tissue which suggest the possible association of pelvic lipomatosis with congenital venous anomalies. The differential diagnosis of pelvic lipomatosis includes perivesical hematoma secondary to trauma which can be diagnosed by history and demonstration of a pelvic fracture. One patient with radiographic evidence suggestive of pelvic lipomatosis was found at exploration to have extensive carcinoma of the prostate with lymph node involvement.’ Inferior vena caval obstruction has been reported to show teardrop deformity of the bladder and also narrowing of the rectum which was attributed to compression of the organs by enlargement of the venous collat-
UROLOGY
/ FEBRUARY
1979
/ VOLUME
XIII,
NUMBER
2
acterized by men more than sixty years of age in whom the disease was found during evaluation of an unrelated problem. He found neither serious sequelae nor significant progression of the lipomatosis in this group. The cases that we are reporting would not fall within those guidelines. Case 1 has been followed for almost two years. The intravenous pyelogram obtained eighteen months after the original one showed no progressive hydronephrotic changes. Our Case 2 has been followed for three years. Intravenous pyelogram has also revealed little change. The 3 patients have remained asymptomatic, with normal renal function. Treatment once the diagnosis had been established either by radiologic means or surgical biopsy has been directed to management of the problems which may arise, primarily ureteral obstruction, and in some of the cases antibiotic therapy when chronic infection was present. Carpenter’ and more recently Ballesterosz3 reported cases successfully treated by surgical removal of the fatty deposits with significant improvement of the changes present on excretory urography. Most authors, however, have believed that the surgical removal of the fatty deposits was surgically difficult to accomplish, and in our case which was surgically explored, this was found to be the case. Sacks and Drenick24 reported a case in which prolonged fasting produced an extensive weight loss and profound resolution of his presenting symptoms and radiologic abnormalities. Subsequent regain of weight resulted in reappearance of the disorder which they believed proved that pelvic lipomatosis may be a disease of accelerated and excessive fat deposition which could be reversed by dietary restriction.
erals within the pelvis.16 Liposarcoma of the perivesical space could cause deformity of the bladder somewhat suggestive but not quite similar to the one caused by pelvic 1ipomatosis.l’ Lipoplastic lymphadenopathy is a rare, benign disorder of the lymphoid tissue which is replaced by mature fat associated with enlargement of these nodes. Cases involving the pelvic and retroperitoneal nodes have been described. Manning, Pischinger, and BobrofP* reported a case of typical deformity of the bladder and rectum also causing a marked lateral displacement of the left ureter which is not usually associated with pelvic lipomatosis. Diagnosis was established by lymphangiography. O’Dea and Maleklg reported a case of a foreign body in the bladder with perivesical inflammation causing a teardrop deformity. However, a barium enema showed normal findings. Cystoscopic removal of a wooden toothpick led to complete resolution of the bladder deformity on follow-up IVP. Computed tomography is particularly useful in the differential diagnosis of pelvic lipomatosis because of its ability to demonstrate the density of the tissues surrounding the bladder and the rectum, differentiating fat from enlarged lymph nodes, hematomas, dilated blood vessels, or other causes of perivesical masses. Gerson, Gerzof, and Robbins ‘O have reported on the evaluation of 2 patients with pelvic lipomatosis studied with computed tomography. Both patients demonstrated abundant tissue with a density identical to subcutaneous fat surrounding the bladder and rectum with no other mass lesions. Normal tissue planes were preserved in both patients. This report adds 3 more cases to the literature with similar findings on computed tomography. The natural course of this disease is not well known. Patients have been followed for up to eight and nine years with little radiographic change in the pelvic fatty tissue.3.“,‘3 Most of the other cases reported have had a short follow-up. A significant number of patients, however, presented with marked ureteral obstruction and secondary hydronephrosis which require supravesical diversion or ureteral reimplantation. 1,5,14,21,22 Carpenter* separated two general clinical groups from the cases reported. In the first group he included young, stocky, obese men who had vague pelvic symptoms, gross hematuria, or hypertension, but were otherwise in good health. He found them to have a definite risk of progressive ureteral obstruction and uremia. The second clinical group was char-
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FEBRUARY
1979
/
VOLUME
XIII,
NUMBER
Aurora, Illinois 60506 (DR. SUSMANO) ACKNOWLEDGMENT. Deniz, and Dr. Thomas
To Dr. O’Shea.
Chi Feng
Su, Dr.
Engin
References 1. Fogg LB, and Smyth JW: Pelvic lipomatosis: a condition simulating pelvic neoplasm, Radiology 90: 558 (1968). 2. Engels EP: Sigmoid colon and urinary bladder in high fixation: roentgen changes simulating pelvic tumor, ibid. 72: 419 (1959). 3. Moss AA, Clark RE, and Goldberg HI: Pelvic lipomatosis: a roentaenonraphic diaenosis, A.I.R. 115: 411 (1972). 4. hatten jr, HP,Ch&g UP, and Rosenbaum HD: When is biopsy necessary in pelvic lipomatosis? Urology 9: 333 (1977). 5. Radinsky S, Cabal E, and Shields J: Pelvic lipomatosis, ibid. 7: 108 (1976).
2
219
6. Abbott DL, and Skinner DC: Congenital venous anomalies associated with pelvic lipomatosis - a case report, J. Ural. 112: 739 (1974). 7. Nussbaum PS: Carcinoma of the prostate presenting as pelvic lipomatosis, Surg. Clin. North Am. 52: 405 (1972). 8. Carpenter AA: Pelvic lipomatosis: successful surgical treatment, J. Ural. 110: 97 (1973). 9. Morettin LB, and Wilson M: Pelvic lipomatosis, A.J.R. 113: 181 (1971). 10. Rosenberg B, Hurwitz A, and Hermann H: Demum’s disease with unusual retroperitoneal and paravesical fatty infiltration, Surgery 54: 451 (1963). 11. Goldstein HM, and Vargas CA: Pelvic lipomatosis in females, J. Can. Assoc. Radiol. 2% 65 (1974). _ 12. Schechter LS: Venous obstruction in oelvic lioomatosis, 1. Ural. 111: 757 (1974). 13. Becker JA, et ol: Pelvic lipomatosis - a consideration in the diagnosis of intrapelvic neoplasms, Arch. Surg. 160: 94 (1970). 14. Yalla SV, Ivker M, Burros HM, and Dorey F: Cystitis glandularis with pelvic lipomatosis, Urology 5: 383 (1975). 15. Susmano D, Rubenstein AB, D&in A, and Lloyd FA: Cystitis elandularis and adenocarcinoma of the bladder, 1. Urol. 105: 671 (y971).
220
16. Amoe HE, Jr, and Lewis RE: Urographic and barium enema appearance in inferior vena cava obstruction, Radiology 108: 397 (1973). 17. Femicola A: Liposarcoma of paravesical space, Urology 6: 252 (1975). 18. Manning LG, Pischinger RJ, and Bobroff LM: Lipoplastic lymphadenopathy simulating malignant lymphoma and pelvic lipomatosis. Report of a case and review of the literature, J. Ural. 114: 788 (1975). 19. O’Dea MJ, and Malek RS: Foreign body in bladder and perivesical inflammation masquerading as pelvic lipomatosis, ibid. 116: 669 (1976). 20. Gerson ES, Gerzof SG, and Robbins AH: CT confirmation of pelvic lipomatosis: two cases, A. J.R. 129: 338 (1977). 21. Pepper HW, Clemett AR, and Drew JE: Pelvic lipomatosis causing urinary obstruction, Br. J. Radiol. 44: 313 (1971). 22. Golding PL, Singh M, and Worthington B: Bilateral ureteral obstruction caused bv, -oelvic liwmatosis. Br. I. Sure. 59: 69 23. Ballesteros JJ: Surgical treatment of perivesical lipomatosis, J. Ural. 118: 329 (1977). 24. Sacks SA, and Drenick EJ: Pelvic lipomatosis: effect of diet, Urology 6: 609 (1975).
UROLOGY
/
FEBRUARY
1979
/
VOLUME
XIII,
NUMBER
2
TOMOGRAPHY
IN DIAGNOSIS
OF
LIPOMATOSIS E. SUSMANO, H. DOLIN,
M.D.
M.D.
From the Departments of Surgery (Urology) Mercy Center for Health Care Services, Aurora, Illinois
and Radiology,
ABSTRACT - Pelvic lipomatosis is a disease characterized by abnormal deposition of mature adipose tissue within the confines of the pelvis surrounding the bladder, prostate, and rectosigmoid. The presenting symptoms are vague and nonspecijc, and it has typical radiologic features. Computed tomography is extremely useful in the di&ferential diagnosis because of its ability to differentiate fatty infiltration from other conditions which can cause elevation and compression of the urinary bladder and sigmoid colon. Computed tomographic confirmation of the presence of fat surrounding the bladder and rectum eliminates the need for surgical biopsy, unless indicated fw other reasons. The course of this disease is usually benign and indolent, however a close follow-up is mandatory to rule out those cases in which ureteral obstruction may develop requiring surgical relief of the obstruction. When cystitis glandularis is found in association with pelvic lipomatosis, periodic cystoscopic examinations are recommended because of the potential risk of malignant transformation.
Pelvic lipomatosis is a term coined by Fogg and Smyth in 1968l to describe an entity first reported by Engels in 195g2 and characterized by an overgrowth of normal fatty tissue limited to the perirectal and perivesical spaces in the pelvis. There is increased awareness of this disease as more cases are being reported in the lithowever it is likely that pelvic erature, lipomatosis is a more common disease than has been reported to date. Typical radiologic features of tear-shaped deformity of the bladder, increased radiolucency of the pelvic soft tissues, and elevation of the bladder and rectosigmoid outside the pelvis led some authors to believe that pelvic lipomatosis has pathognomonic radiologic findings which when present eliminate the need for surgical biopsy.3-5 To the contrary, others believe that tissue diagnosis is mandatory and that negative findings at biopsy should not be looked upon as unnecessary surgery.6-8 This article reports 3 cases of pelvic lipomatosis which we have had the opportunity to study with computed tomography (CT)
UROLOGY
/ FEBRUARY
1979 / VOLUME
XIII,
NUMBER
which we believe has a definite role in the diagnosis of this pathologic entity. All CT scans were performed on an EMI CT 5005 total body scanner. Scan time per slice was twenty seconds. Contrast enhancement scans were obtained after the intravenous infusion of 300 cc. of contrast material (Reno-M-Dip). Case Reports Case 1 This fifty-year-old black man (height 6 feet 3 inches, weight 245 pounds) was admitted because of persistent pain in the right lower abdominal quadrant and right inguinal pain. No gastrointestinal or genitourinary symptoms were present, and physical examination was unremarkable. Laboratory data were within normal limits except for a slight elevation of the serum alkaline phosphatase level. Upper gastrointestinal and gallbladder x-ray films were normal. Barium enema showed a fusiform appearance with elongation of the rectosigmoid (Fig. 1A). An
2
215
FIGURE 1. Case 1 (A) Barium enema showing fusiform appearance with elongation of rectosigmoid. (B) IVP showing mild bilateral ureteral dilatation, deformity of the bladder, and increased radiolucency of tissue surrounding bladder. (C) Computed tomography: bladder and rectum symmetrically surrounded by low density tissue with same absorption value as subcutaneous fat.
A intravenous pyelogram (IVP) showed mild bilateral ureteral dilatation with marked elevation of the floor of the bladder which also appeared to be displaced anteriorly (Fig. 1B). Cystoscopic examination was difficult to perform because of the marked elevation of the floor of the bladder and elongation of the prostatic urethra. The instrument barely entered the bladder. Minimal changes of cystitis cystica were noted. Exploratory surgery was performed on August 4, 1975. A tremendous proliferation of normalappearing fatty tissue was encountered intimately attached to the pelvic bone and completely surrounding the bladder and rectum.
Multiple biopsy specimens were taken. The peritoneum and bladder were entered during the dissection. It was considered impossible to remove completely all the fatty tissue. He had an uneventful postoperative course. Findings on IVP in December, 1975, were unchanged. The patient was readmitted to the hospital in March, 1977, because of recurrent pain in the right lower abdominal quadrant. IVP showed no progressive hydronephronic changes. Renal function remained normal. On computed tomography the bladder and rectum were symmetrically surrounded by low density tissue with the same absorption value as subcutaneous
FIGURE 2. Case 2. (A) IVP showing mild bilateral ureteral dilatation, deformity of bladder, and marked elevation of floor of bladder. (B) Barium enema showing typical deformity of rectosigmoid which appeared elevated out of pelvis. (C) Computed tomography showing similar findings to Case 1.
216
UROLOGY
/ FEBRUARY
1979 / VOLUME XIII, NUMBER 2
FIGURE 3. Case 3. (A) IVP showing normal upper tracts and deformity of bladder with elevation of floor of bladder. (B) Computed tomography again shows bladder and rectum surrounded by increased amount of low density tissue with same absorption value as subcutaneous fat.
fat (Fig. 1C). Absorption values ranged from -18 EM1 units to -70 EM1 units with a mean density of -40 EM1 units. Normal tissue planes were preserved. Case 2
The patient (height 5 feet 6 inches, weight 155 pounds) was first admitted to the hospital at age thirty-seven years. This was in July, 1974, because of suprapubic discomfort, occasional burning on urination, and terminal hematuria. IVP showed deformity of the bladder with elevation of the floor of the bladder and normal upper tracts (Fig. 2A). Cystoscopy revealed several papillary growths involving the bladder neck, trigone, and posterior urethra. Multiple biopsy specimens were taken and reported as cystitis glandularis. Cystogram showed a tearshaped bladder. Cystoscopic examination since then with biopsies of the involved areas revealed no changes in the histologic appearance of the lesion. Repeat IVP in March, 1976, showed no change in comparison with the IVP obtained in 1974. Barium enema demonstrated typical deformity of the rectosigmoid which appeared elevated out of the pelvis (Fig. 2B). Findings on computed tomography were similar to those in Case 1 (Fig. 2C). Case 3
This forty-four-year-old white man (height 6 feet 4 inches, weight 240 pounds) had a twoyear history of hypertension. A timed IVP showed slight differential dye excretion of the contrast material through both kidneys, also an oval-shaped configuration of the bladder with elevation of the floor of the bladder (Fig. 3A). There were no urinary tract symptoms. A workup for hypertension including an arteriogram
UROLOGY
/
FEBRUARY
1979 / VOLUME XIII, NUMBER 2
was negative. Cystogram showed a tear-shaped bladder with elevation of the floor of the bladder suggestive of pelvic lipomatosis. A barium enema revealed narrowing and elongation of the rectosigmoid caused by a radiolucent pelvic mass. Findings on computed tomography were similar to those in Case 1 (Fig. 3B). There was no evidence of lymphadenopathy, hematoma, or other condition which may simulate pelvic lipomatosis. Cystoscopy revealed minimal changes of cystitis cystica. Follow-up IVP six months later showed no change in the appearance of the bladder with no ureteral dilatation. The patient remained asymptomatic. The blood pressure has remained under control with triamterene and hydrochlorothiazide (Dyazide) and methyldopa (Aldomet). Comment The cause of pelvic lipomatosis remains uncertain, although several different opinions have been expressed. Engels suggested that pelvic lipomatosis resulted from chronic lower urinary tract infection. There had been, however, numerous cases of patients with no urinary symptoms and negative findings on urinalysis. Others have considered it to be a localized form of obesity. If this were the case, however, one would expect to encounter this abnormality fi-equently.g Rosenberg, Hurwitz, and Hermann’O suggested that pelvic lipomatosis may represent a variant of Dercum disease with retroperitoneal and perivesical fatty infiltration. Pelvic lipomatosis occurs predominantly in men, those between the ages of twenty-five to forty years being the most commonly affected. Only 3 cases have been reported in womenll and a single pediatric casee3 In those cases in which surgical exploration was performed, the bladder, prostate, and rectum have been found
217
to be enveloped but not invaded by dense, vascular, nonencapsulated lipomatous tissue. This fibrolipomatous tissue will occasionally extend outside of the pelvis into the retroperitoneal area surrounding the ureters and vena cava.12 The histologic findings have been of mature adipose tissue or with variable amount of fibrous matrix and chronic inflammatory cells. The nonencapsulation differentiates this condition from a true lipoma. The symptoms of patients with pelvic lipomatosis are nonspecific. Some present with genitourinary symptoms, frequency, dysuria, and difficulty starting urination. l-3,13 Gastrointestinal symptoms occur less frequently and may present as mild constipation. A significant number of cases have been diagnosed at evaluation for unrelated problems, especially hypertension. 3,5~14The significance of the apparent relation of hypertension to pelvic lipomatosis is not clear and may be a fortuitous occurrence. The physical findings also are often nonspecific. Mild obesity may be present. Abdominal examination may reveal a vague suprapubic mass. On rectal examination the prostate is characteristically found high in position owing to elevation from the fatty tissue. A pelvic mass representing the adipose tissue can be palpated on rectal examination. Because of elevation of the bladder base and deformity of the sigmoid colon, performance of sigmoidoscopy and cystoscopy are characteristically difficult. Laboratory tests usually reveal normal renal, liver, and endocrine function. The radiologic manifestations are more characteristic including: (1) increased radiolucency of the soft tissues of the pelvis which is due to the low radiographic density of the excess fat that surrounds the bladder and the rectum; (2) elevation out of the pelvis of the urinary bladder which often is teardrop or gourd in configuration; (3) elongation and narrowing of the rectosigmoid with an intact colonic mucosa. The intravenous pyelogram often reveals medial deviation of the distal ureters and mild to sometimes severe dilatation and lateral displacement of the mid and upper ureters. Sigmoidoscopy when it has been performed has confirmed the straightening of the colon and absence of intrinsic lesions. Cystoscopic examination has been difficult to perform because of marked elongation of the prostatic urethra. When successful, it has revealed the frequent association of various forms of proliferative cystitis with pelvic lipomatosis.14 Cystitis follicularis, cystitis cystica, and cystitis glandularis
218
have been found and confirmed by histologic examination. These various forms of proliferative cystitis are known to develop in the presence of chronic irritation due to infection or obstruction. Whether a chronic inflammatory reaction leads to the development of the proliferative cystitis and the pelvic lipomatosis or whether pelvic lipomatosis somehow is responsible for initiating the glandular metaplasia is still debatable. Adenocarcinoma of the bladder has been reported to arise from cystitis glandularis.15 There have been no reports, however, of this complication in association with pelvic lipomatosis, but the assumption should probably be made that cystitis glandularis in any setting is a premalignant condition.8 All our patients had a cystoscopic examination. In Case 1 it was technically difficult to perform, but minor changes of cystitis cystica were encountered as in Case 3. Case 2 presented with hematuria. Cystoscopy revealed severe vesical changes of cystitis glandularis which had been confirmed with multiple biopsies since he was first seen in 1974. Schechter in 197412 reported a case of pelvic lipomatosis associated with inferior vena caval and external iliac vein obstruction which on surgical exploration revealed a large amount of fibrous fatty tissue around the bladder and the inferior vena cava, also causing extrinsic pressure defects on the pelvic veins which he believed was the cause of the venous obstruction. Also in 1974 Abbott and Skinner’ reported a case in which complete occlusion of the inferior vena cava in association with pelvic lipomatosis was encountered. They believed that the obstruction of the inferior vena cava was of congenital origin. They also pointed out the high incidence of postoperative thrombophlebitis noted in these patients and the remarkable vascularity associated with this fatty tissue which suggest the possible association of pelvic lipomatosis with congenital venous anomalies. The differential diagnosis of pelvic lipomatosis includes perivesical hematoma secondary to trauma which can be diagnosed by history and demonstration of a pelvic fracture. One patient with radiographic evidence suggestive of pelvic lipomatosis was found at exploration to have extensive carcinoma of the prostate with lymph node involvement.’ Inferior vena caval obstruction has been reported to show teardrop deformity of the bladder and also narrowing of the rectum which was attributed to compression of the organs by enlargement of the venous collat-
UROLOGY
/ FEBRUARY
1979
/ VOLUME
XIII,
NUMBER
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acterized by men more than sixty years of age in whom the disease was found during evaluation of an unrelated problem. He found neither serious sequelae nor significant progression of the lipomatosis in this group. The cases that we are reporting would not fall within those guidelines. Case 1 has been followed for almost two years. The intravenous pyelogram obtained eighteen months after the original one showed no progressive hydronephrotic changes. Our Case 2 has been followed for three years. Intravenous pyelogram has also revealed little change. The 3 patients have remained asymptomatic, with normal renal function. Treatment once the diagnosis had been established either by radiologic means or surgical biopsy has been directed to management of the problems which may arise, primarily ureteral obstruction, and in some of the cases antibiotic therapy when chronic infection was present. Carpenter’ and more recently Ballesterosz3 reported cases successfully treated by surgical removal of the fatty deposits with significant improvement of the changes present on excretory urography. Most authors, however, have believed that the surgical removal of the fatty deposits was surgically difficult to accomplish, and in our case which was surgically explored, this was found to be the case. Sacks and Drenick24 reported a case in which prolonged fasting produced an extensive weight loss and profound resolution of his presenting symptoms and radiologic abnormalities. Subsequent regain of weight resulted in reappearance of the disorder which they believed proved that pelvic lipomatosis may be a disease of accelerated and excessive fat deposition which could be reversed by dietary restriction.
erals within the pelvis.16 Liposarcoma of the perivesical space could cause deformity of the bladder somewhat suggestive but not quite similar to the one caused by pelvic 1ipomatosis.l’ Lipoplastic lymphadenopathy is a rare, benign disorder of the lymphoid tissue which is replaced by mature fat associated with enlargement of these nodes. Cases involving the pelvic and retroperitoneal nodes have been described. Manning, Pischinger, and BobrofP* reported a case of typical deformity of the bladder and rectum also causing a marked lateral displacement of the left ureter which is not usually associated with pelvic lipomatosis. Diagnosis was established by lymphangiography. O’Dea and Maleklg reported a case of a foreign body in the bladder with perivesical inflammation causing a teardrop deformity. However, a barium enema showed normal findings. Cystoscopic removal of a wooden toothpick led to complete resolution of the bladder deformity on follow-up IVP. Computed tomography is particularly useful in the differential diagnosis of pelvic lipomatosis because of its ability to demonstrate the density of the tissues surrounding the bladder and the rectum, differentiating fat from enlarged lymph nodes, hematomas, dilated blood vessels, or other causes of perivesical masses. Gerson, Gerzof, and Robbins ‘O have reported on the evaluation of 2 patients with pelvic lipomatosis studied with computed tomography. Both patients demonstrated abundant tissue with a density identical to subcutaneous fat surrounding the bladder and rectum with no other mass lesions. Normal tissue planes were preserved in both patients. This report adds 3 more cases to the literature with similar findings on computed tomography. The natural course of this disease is not well known. Patients have been followed for up to eight and nine years with little radiographic change in the pelvic fatty tissue.3.“,‘3 Most of the other cases reported have had a short follow-up. A significant number of patients, however, presented with marked ureteral obstruction and secondary hydronephrosis which require supravesical diversion or ureteral reimplantation. 1,5,14,21,22 Carpenter* separated two general clinical groups from the cases reported. In the first group he included young, stocky, obese men who had vague pelvic symptoms, gross hematuria, or hypertension, but were otherwise in good health. He found them to have a definite risk of progressive ureteral obstruction and uremia. The second clinical group was char-
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Aurora, Illinois 60506 (DR. SUSMANO) ACKNOWLEDGMENT. Deniz, and Dr. Thomas
To Dr. O’Shea.
Chi Feng
Su, Dr.
Engin
References 1. Fogg LB, and Smyth JW: Pelvic lipomatosis: a condition simulating pelvic neoplasm, Radiology 90: 558 (1968). 2. Engels EP: Sigmoid colon and urinary bladder in high fixation: roentgen changes simulating pelvic tumor, ibid. 72: 419 (1959). 3. Moss AA, Clark RE, and Goldberg HI: Pelvic lipomatosis: a roentaenonraphic diaenosis, A.I.R. 115: 411 (1972). 4. hatten jr, HP,Ch&g UP, and Rosenbaum HD: When is biopsy necessary in pelvic lipomatosis? Urology 9: 333 (1977). 5. Radinsky S, Cabal E, and Shields J: Pelvic lipomatosis, ibid. 7: 108 (1976).
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6. Abbott DL, and Skinner DC: Congenital venous anomalies associated with pelvic lipomatosis - a case report, J. Ural. 112: 739 (1974). 7. Nussbaum PS: Carcinoma of the prostate presenting as pelvic lipomatosis, Surg. Clin. North Am. 52: 405 (1972). 8. Carpenter AA: Pelvic lipomatosis: successful surgical treatment, J. Ural. 110: 97 (1973). 9. Morettin LB, and Wilson M: Pelvic lipomatosis, A.J.R. 113: 181 (1971). 10. Rosenberg B, Hurwitz A, and Hermann H: Demum’s disease with unusual retroperitoneal and paravesical fatty infiltration, Surgery 54: 451 (1963). 11. Goldstein HM, and Vargas CA: Pelvic lipomatosis in females, J. Can. Assoc. Radiol. 2% 65 (1974). _ 12. Schechter LS: Venous obstruction in oelvic lioomatosis, 1. Ural. 111: 757 (1974). 13. Becker JA, et ol: Pelvic lipomatosis - a consideration in the diagnosis of intrapelvic neoplasms, Arch. Surg. 160: 94 (1970). 14. Yalla SV, Ivker M, Burros HM, and Dorey F: Cystitis glandularis with pelvic lipomatosis, Urology 5: 383 (1975). 15. Susmano D, Rubenstein AB, D&in A, and Lloyd FA: Cystitis elandularis and adenocarcinoma of the bladder, 1. Urol. 105: 671 (y971).
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16. Amoe HE, Jr, and Lewis RE: Urographic and barium enema appearance in inferior vena cava obstruction, Radiology 108: 397 (1973). 17. Femicola A: Liposarcoma of paravesical space, Urology 6: 252 (1975). 18. Manning LG, Pischinger RJ, and Bobroff LM: Lipoplastic lymphadenopathy simulating malignant lymphoma and pelvic lipomatosis. Report of a case and review of the literature, J. Ural. 114: 788 (1975). 19. O’Dea MJ, and Malek RS: Foreign body in bladder and perivesical inflammation masquerading as pelvic lipomatosis, ibid. 116: 669 (1976). 20. Gerson ES, Gerzof SG, and Robbins AH: CT confirmation of pelvic lipomatosis: two cases, A. J.R. 129: 338 (1977). 21. Pepper HW, Clemett AR, and Drew JE: Pelvic lipomatosis causing urinary obstruction, Br. J. Radiol. 44: 313 (1971). 22. Golding PL, Singh M, and Worthington B: Bilateral ureteral obstruction caused bv, -oelvic liwmatosis. Br. I. Sure. 59: 69 23. Ballesteros JJ: Surgical treatment of perivesical lipomatosis, J. Ural. 118: 329 (1977). 24. Sacks SA, and Drenick EJ: Pelvic lipomatosis: effect of diet, Urology 6: 609 (1975).
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