Carcinoma of the bladder: characteristic modes of local invasion.

It is now fairly generally agreed that the type of treatment to be chosen for an infiltrating carcinoma of the bladder will depend at least to some e:-:tent upon the depth to which this tumor has invaded the wall of the .bladder. However, the preoperative estimate of this depth of infiltration cannot be expected to equal in precision the postoperative or postmortem findings based. , upon the study of the · whole thickness of the bladder wall. But any information that .might increase the accuracy of one's preoperative estimate should be fully utilized. Preoperative segregation, by biopsy of the bladder wall and bimanual palpation of the bladder, is usually simple in most cases of small superficial tumors and large deep tumors. There are two situations, however, in which misinterpretation of the pr-eliminary findings. results in the preoperative classification of the tumor as superficial when in reality it is very deep. These two sources of error are attributable to the manner in which certain tumors invade the wall of the bladder, and the first is illustrated by the following case. A 56-year~old man (B.U.I. 55800) was referred on De9ember 3, 1956 because of intractable vesical irritability 14 months in duratio.n. In the beginning the .. urine was sterile and. biopsies had shown only chronic inflammation. On admissiOJ! . the only positive findings were pyuria with drug-resistant bacilli', a small bladder ~apacity, and bullou'S edema of the trigone and_ bladder neck. Biopsies again revealed only chronic cystitis. After 7 months of regular treatment I . with instillations and irrigations scattered areas of splotchy reddening were visible and biopsy of these showed marked epithelial pleomorphism suggestive of noninvasive carcinoma. On October 24, 1957 a number of small papi,llary tumors were present ·and these on biopsy were found to consist of poorly differentiated squamous carcinoma; invading only the superficial muscle and several nearby lymphatics. The outlook was considered favorable because of only superficial infiltration . -Read at annual meeting of American Associa· twn of Genito-Urinary Surgeons, Absecon, N.·J.,_ Aprill5-17, 1959. · as disclosed by transurethral biopsies, and on November 11, 1957, the urine was diverted by an ileal loop, and the bladder removed. Retroperitoneal ·metastases were present. Sections through the bladder wall showed poorly differentiated squamous carcinoma invading . as a mass only as far as the superficial portion of the musculature but metastasizing through the lymphatics to the perivesical fat and prostate (figs. 1 and 2). Following discharge from the hospital the patient's course was steadily downhill and he died on January 14, 1958. At postmortem examination widespread metastases were found in nodes, liver, and bone-marrow. . The first error was the apparently unavoidable delay in finding this elusive tumor; the error in judging it to be superficial, and therefore localized to the bladder, lay in the failure to recognize the significance of local lymphatic involvement a.S shown by biopsy. Whenever such involvement can be demonstrated, the likelihood bf intramurai metastasis is always considerable. To see how often tumors metastasized through the bladder wall in this !D-anner, microscopi~ slides of 303 cases of infiltrating carcinoma of the bladder were critically studied. These sections had been taken from specimens obtained by autopsy, cystectomy, and segmental resection. The cases ·were sep_arated into the following 4 stages of infiltration: A, submucosa only; B1, less than halfway through the muscle; B2, halfway or more through the muscle; C; perivesical fat or prostate, Fifty-one cases had to be eliminated from the 206 in stage.C because of insufficient data, leaving 155 in this group. The total series therefore consisted of 252 cases (table 1). Although the lymphatics ·were found to be invaded at some level in the bladder wall in 7~ cases (31 per cent), they were involved in only seven _in which the tumor had failed to eXtend to the halfway level in the muscle wall. Of these seven, · only two, both poorly differentiated squamous cancers, metastasized to a depth .greater than that reacb,ed by the primary growth. The results. of a detailed analysis of the relation-