Percutaneous Aspiration of Selected Expanding Renal Lesions

PERCFL\.KEOCS ASPIRATION OF SELECTED EXPANTHNG RENAL LESIONS JAMES H. DEWEERD /?rnrn the Scrhon of Urology, il1ayo Clinfr ,rnd Mayo Foundation. Rochcslci, Minn.

;\ qniek glance through the urologic literature of the past decade or two will serve to point up the well-establishrcl fact that the differential diagnosis und treatment of renal 1mrnses han, twen, und prnbabl)- will continue to be, of major com·ern to the urologist. His concern is shaq,ly focmrd on the fact thn.t extirpation of the maligmmt renal lesion continues to be the nal lesions. Some: han, thought that all expanding renal ksions slwuld be: explored and that the .,imple or sermrn c.rnt, 01' at least it,c; free Rend ;it annual meeting of Amcriea11 Associat.io11 of Genito- l:rinan· ::.;urgeons, Las 'Vegas. :'\cvada., [7-19, HJIH. 1 l'rather, C.: SurgicaJ treatment of serous c,,st of 1.he kidney. J. Urol ., 77: 14-18, Hl57. 'Clarke, B. C., Goade. W. J, .Jr., Ruch·, ILL. and Rockwood, Lawrence Differential diagnosis between r,ancer and serous cyst of the kidney . .J. UroL, 75: 922-\)29,

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wau,1. 2 should be pxciscd lwcalrnc of local prec1-· sure plwnomena, destruction of renal cortical tissue, danger of infection, a,Rsociated hypertension, danger of rupture and hC'rnorrhage, :we! the possibility of carcinoma in the 01 associated carcinoma. J:-Iowun,r, tlw muin con. cern seems to be, and rightfull.v should the urologist's inability to be certain that the lesion is a erst and not a malignant tumor. It would appear further that, except when pressure canses symptoms or urographic evidence of obstruction llnd therefore parcud1~·mal darrrngc or when infection, hypertension m liemonbagc: ente:rn the clinical picture, the justification for attack on any gi\·eu simple sen>us cyst lies in tlw production of irrefutable C'viclcm·e that the lesion is henign and not DTAGKOST!C CONSIDEHATfONc,

I shall not belabor the mutter of differential diagno,is het,veen cyst aud tumor. The litc:mt111·1· is replete with rccmmts of the urographic featurf's of cach. 3·'' One would be inclined to condurk that the gamut of procedmc8 including excretory urographr, retrograde pydography, and intran,nous arkriography, ncphrogrnphY and nephrotomogmphy, 1d1en coupled with the clinical appraisal, should prodL1ce the diagnosi:s, ac; indeed it will in manr cases. Diagnmis oftc,n depends not on the clinicaJ and findings set dmrn in rote fashion like puzzle, but on the uroJogist's experiencr, and acumen. In many sitmttions of any total, the clinical ancl laboratory findings plu~ an cxcretor.v urograrn ffill suffice to permit categoric: conclusion that a gin,n lesion is renal neoplasm and that surgical intervention 12 indicated. The information prmlucl'd by the retrograde,'. pyelogram has enabled and wi I! continue to enable the urologist to add to the 3 Ochsner, H. C. · H.oentgenol., 65:

of the kidney. Arn 19.51.

4 Shivers, C. H. deT. and clinical comparison bet.ween benign cysts ,rnd malignant lesions of the renal parenchynrn. Urol., 79: 36:3--3G7, HJ58. 'Prather, G. C. · Different,ial diagnosis betwPen renal tumor n.ml renal cyst J. 1Jrol , 64: 19:l-Hlfl lD50. "

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number of cases in which he would do an exploration without further specific examination. At this point of the investigation a large percentage of any given number of lesions must be categorized as being either a cyst or a tumor, and only in the rare case does one have the courage to state dogmatically, "this is a renal cyst, I advise observation." Interest and experience enable us to state a preferred diagnosis, but each of us can point to cases in which our most considered opinions have been wrong. It is this eA'})erience, I am sure, that has induced leading urologists to decree that "solitary cysts deserve exploration."1 • 4 • 5 Aortography promised for a time to aid in the distinction between tumor and cyst. However, several inconclusive results and experience with false-negative reports dampened the enthusiasm that my colleagues and I may have had for this procedure. Recently, we have improved our technique and have greatly increased the use of intravenous arteriography and nephrotomography which, we believe, will prove more informative and reliable than translumbar aortography. Recent experience with a false-negative report, however, has served to renew my caution in interpretation and evaluation of nephrotomograms. The controversial procedure that is the subject of this presentation is not new. Twenty-two years ago, Dean 6 reported his experience with aspiration in 150 cases of renal tumor. He reported no ill effects and recommended aspiration of renal cysts under local anesthesia, as he had done in 15 patients. In 1951, Ainsworth and Vest,7 believing that exploration was neither necessary nor desirable in most instances of so-called cortical cyst, reported their excellent results with needle puncture as an office procedure in more than 20 cases of large renal mass in which cyst was strongly suspected. Only one tumor was encountered in their series. Lindblom,8 in 1952, reported the aspiration of 80 renal lesions under local anesthesia, this being done simultaneously with excretory urography or retrograde pyelography. Forty (50 per cent) 6 Dean, A. L.: Treatment of solitary cyst of the kidney by aspiration. Trans. Am. A. G-U Surg.,

32: 91-95, 1939.

7 Ainsworth, W. L. and Vest, S. A.: The differential diagnosis between renal tumors and cysts. J. Urol., 66: 740-749, 1951. 8 Lindblom, K.: Diagnostic kidney puncture of cysts and tumors. Am. J. Roentgenol., 68: 209-215,

1952.

of the lesions were cysts, 34 were renal tumors, three were pararenal tumors and three were normal renal structures; during the same period, 59 patients were operated on without aspiration, representing 55 hypernephromas and four pelvic tumors. Nineteen years ago, Wheeler 9 reported the aspiration of two renal cysts under anesthesia. My personal interest in this procedure was stimulated in 1955 when I was confronted with the problem of an asymptomatic, accidentally discovered renal mass in the 70-year-old mother of a medical colleague. All evidence pointed to the probability of renal cyst. The patient, anxious to avoid an operation, was content to let the matter rest there, but the physician-son as well as his brothers and sisters, realizing that there was still some uncertainty about the diagnosis, was loath to allow a shadow of doubt to obscure the future of his remarkably wellpreserved mother. The resolution of this doubt for all concerned by aspiration of the lesion under anesthesia was highly satisfactory. SELECTION OF PATIENTS AND PERFORMANCE OF PROCEDURE

Being mindful of the criticism leveled against aspiration procedures, I developed a modus operandi that to me seems logical and sound, provides maximal security with minimal risk, and avoids the morbidity, risk and expense incident to surgical exploration. The criteria that were gradually evolved and rather firmly adhered to, to provide a carefully selected group of patients for aspiration, are as follows: 1) An expanding renal lesion which urographically (a) is solitary, (b) does not jeopardize renal function by obstruction, excessive distortion or compression, and (c) conforms to urographic findings consistent with a solitary cyst. 2) Such an expanding lesion in a patient who (a) has not had asymptomatic gross hematuria, (b) has no symptoms referable to the upper part of the urinary tract, (c) has no increase of the erythrocyte-sedimentation rate, (d) has no signs or symptoms of occult malignant tumor, (e) has reached middle age or is older, and (f) has other problems (eye, orthopedic, and so forth) for which an elective operation hinges on resolution of the renal diagnosis. 9 Wheeler, B. C.: Use of the aspirating needle in the diagnosis of solitary renal cyst. New Eng. J. Med., 226: 55-57, 1942.

PERCUTANEOUS ASPIRATION OF RENAL LESIONS

In such a situation I acquaint the patient with his problem and tell him that although the lesion may be either a tumor or a cyst and although I strongly favor the latter diagnosis, I cannot be certain. The procedure is as follows: 1) Patient is hospitalized and prepared for exploration of the kidney. 2) Patient is anesthetized, positioned and draped for renal exploration (fig. 1). 3) Preliminary percutaneous aspiration of renal lesion is done (fig. 2). 4) Diagnosis of simple serous cyst is made if (a) crystal-clear (usually light-yellow) fluid is

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obtained in quantities of 15 cc or more, (b) Papanicolaou stain of centrifuged specimen of fluid fails to demonstrate malignant cells, and (c) injection of contrast medium demonstrates cystic space conforming with urographic deformity of expanding lesion without intracystic filling defects (fig. 3). 5) Intermediate incision and exploration of the kidney are done if (a) blood, (b) bloody fluid, (c) cloudy or turbid fluid, or (d) tissue or debris is aspirated. OBSERVATI0N5

During the 6-year period 1955 through 1960 I followed this general scheme of selection and treatment in 212 cases of renal mass. Exclusion of

FIG. 1. Position of patient for aspiration and possible exploration through flank.

FIG. 3. Large smooth-walled cyst of upper pole confirmed by roentgenogram made after injection of contrast medium.

FIG. 2. a, Equipment includes 25 cc syringe, 6 inch 20 gauge needles with obturator, and urographic medium. b, Successful aspiration produces crystal-clear, light-yellow fluid in quantities of 15 cc or more.

Fm. 4. a, Urographic deformity caused by small expanding lesion of left kidney is evident. b, Opaque medium outlines cyst.

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19 cases of tumor origmating in the renal pelvis, 12 cases of vVilms tumor, and 2 cases of angiolipoleiomyoma leaves 179 cases which are made up of 101 cases of renal cyst and 78 cases of renal adenocarcinoma. Fifty-nine, or 33 per cent, of the 179 cases were considered suitable for attempted aspiration. In 42 of the 59 cases, a cyst (fig. 4) was diagnosed on the basis of the criteria outlined, and exploration was not clone. In the other 17

cases, blood or bloody fluid, cloudy fluid, or debris was aspirated and immediate exploration revealed nine additional cysts. Two of the nine cysts were rnultilocular (aspiration had produced only a few cubic centimeters of clear fluid) (fig. 5), one contained crystalline material thought to be the result of ancient hemorrhage, and one was filled with old degenerated blood pigment (fig. 6). Blood-tinged fluid was obtained from the other five cysts. The blood was attrib-

Fm. ,5. a, Urographic deformity of calyces in lower pole. b, Multilocular cyst excised after aspiration had produced only few cubic centimeters of fluid.

Fm. 6. Huge benign cyst, although asymptomatic, had been site of ancient hemorrhage.

PERCUTANEOUS ASPIRATION OF RENAL LESIONS

uted 1) to passage of the needle through normal renal tissue before encountering the cyst as was true in 3 cases of intrarenal or subcortical cysts less than 3 cm. in diameter (fig. 7), or 2)

Fm. 7. Urographic deformity caused by small intrarenal or subcortical cyst; aspiration failed.

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to abrasion of the far wall of the cyst, which may occur in any case but is more likely when the cyst is small. In eight of the 17 cases, adenocarcinoma of the kidney was found and nephrectomy was performed after attempted percutaneous aspiration. In four of these 8 cases, special circumstances led me to disregard the established criteria for percutaneous aspiration, and failure to demonstrate a cyst came as no surprise. One hundred and twenty, or 67 per cent, of the 179 renal masses were explored without preliminary aspiration. Fifty of these proved to be cysts and 70 adenocarcinomas. The average age of the 59 patients subjected to preliminary aspiration was 61 years and the range 41 to 82. Five patients with proved renal cysts had a history of gross hematuria secondary to disease in the lower part of the urinary tract. One patient with asymptomatic gross hematuria had a recurrent stone in one kidney and a hypernephroma in the other. Only one patient had symptoms of distress referable to the kidney in question. He proved to have a hypernephroma. Twenty-one of 51 patients with proved renal cyst and four of eight patients with tumor

Fm. 8. a and b, Large right renal cyst disappeared after single puncture with aspirating needle. c, "Cystogram" demonstrates diffusion of medium outside cyst.

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had microhematuria, grade 1 to 3, at the time of initial urinalysis. Two patients with signs of occult malignant tumor and grossly increased erythrocyte-sedimentation rate were found to have renal malignant tumor after unsuccessful aspiration. Morbidity. Thirty-eight of 42 patients subjected to aspiration either left the hospital or were able to leave the morning after the procedure. One patient was readmitted because of chills and fever 24 hours later. Her illness lasted 36 hours. She subsequently has remained well without signs of renal infection. Two patients, both elderly and obese, complained of transitory tenderness in the opposite flank, apparently due to the exaggerated position on the operating table. The 8 patients who proved to have carcinoma have been observed carefully for signs of recurrence in the flank. So far, none have had such a recurrence, four having been obser-rnd for more than 4 years. All are alive and well except a 75year-old man who is quite debilitated. COMMENT

I chose to perform percutaneous aspiration of selected renal masses with the patient under general anesthesia, rather than to perform it under local anesthesia as an office procedure, because 1) strict asepsis is available in the opera ting room, 2) optimal position is possible ,vithout discomfort to the patient, 3) apprehension on the patient's part is avoided, 4) the surgeon's maneuvers are not hampered by the patient's reactions and movement, 5) multiple attempts at puncture are quickly and easily made, 6) immediate surgical exploration follows unsuccessful puncture, thereby allaying the surgeon's apprehension concerning hemorrhage, continuing spread of malignant cells and the patient's worry that the test failed and operation for cancer is in the offing, and 7) risk of general anesthesia under present-day controlled conditions is minimal. Although the procedure was intended to be purely diagnostic, the cyst disappeared after percutaneous aspiration in five of 14 cases in which appropriate followup studies are available (fig. 8, a and b). Presumably this is due to dissipation of the cyst fluid through the aperture made by the needle in the exceedingly thin cyst wall. Several "cystograms" in this series

demonstrated diffusion of medium. in the retroperitoneal tissues (fig. 8, c). The risk of needling a mass and spreading carcinoma cells must be considered a real one, despite the reports by Dean and others and despite the present report. I do not advocate puncture of all masses, but do believe that, after careful evaluation of all aspects of each case, the risk that a malignant tumor may be needled is small~2 per cent when selective criteria were followed in this series. Four of 70 kidneys operated on without preliminary aspiration were found to contain one or more small cysts occurring simultaneously with adenocarcinoma. These were unsuspected in that they caused no urographic deformity. Conversely, I do not believe that the possibility of finding an unrecognized, unrelated, coincidentally occurring carcinoma is sufficient reason for exploring a simple single cyst. My personal experience and, to the best of my knowledge, the experience of others at the Mayo Clinic do not include a case wherein malignant disease was found in the base of a simple serous cyst that contained clear fluid. Rehm, Taylor and Taylor10 recently described an apparent exception. Critical analysis of other reports of associated cyst and tumor seems to exclude them as points of refutation of the procedure being reported. SUMMARY

Percutaneous aspiration of a carefully selected solitary expanding lesion of the kidney appears to have merit as a procedure that will provide an accurate diagnosis of renal cyst for a significant group of persons without the disability, morbidity and monetary burden imposed by surgical exploration. Fifty-nine (33 per cent) of 179 patients with an expanding renal lesion in this series were considered candidates for percutaneous aspiration, and 42 patients (23 per cent) of the series were spared exploration. Forty-two (71 per cent) of the 59 patients considered candidates for aspiration proved to have cysts that were successfully aspirated. The procedure would seem to find its greatest use in situations wherein specialized techniques, such as intravenous nephrotomography, are not available, cannot be utilized or fail to give a conclusive answer. 10 Rehm, R. A., Taylor, W. N. and Taylor, J. N., Personal communication to the author.