[Comparative study of pure epidermoid carcinoma of the bladder and transitional cell carcinoma with squamous or mixed differentiated foci]. / Estudio comparativo del carcinoma epidermoide de vejiga puro y el carcinoma transicional con focos de diferenciación escamosa o mixto.

INTRODUCTION: The epidermoid bladder carcinoma is an infrequent tumour in our environment accounting for 5-8% of total vesical tumours, but is not so uncommon to find foci of squamous differentiation within a transitional carcinoma. We conducted a comparative study between these two histologic forms and analyzed the pattern of their clinical behaviour. MATERIAL AND METHODS: Retrospective study on a total of 32 cases of epidermoid carcinoma diagnosed between 1986-1996 that following histological confirmation were divided into two groups; plain epidermoid carcinoma (PEC), 11 cases; and transitional carcinoma with foci of squamous differentiation (MEC), 19 cases. After further review 2 cases were excluded. RESULTS: PEC appears in older patients. Both tumoral forms are more frequent in males, the male/female ratio being lower in PEC. Presence of irritative factors is significantly associated to PEC (P < 0.01) and smoking to MEC. Presentation signs are similar in both groups, and haematuria is the most frequent sign. Most usual location in both groups was the trigone, which caused uni/bilateral hydronephrosis in over 50% patients. At the time of diagnosis all PECs were invasive versus only 86% in the MEC group. TREATMENT: PEC group underwent the following procedures: 4 radical cystectomies, 2 cystectomies plus radiotherapy, 3 palliative TUR and 2 TUR with radiotherapy. In the MEC group there were 3 radical cystectomies, 2 cystectomies plus radiotherapy, 1 cystectomy with previous chemotherapy, 8 palliative TUR, 2 TUR with endovesical chemotherapy, 1 TUR with systemic chemotherapy, 1 TUR with radiotherapy and 1 systemic chemotherapy. Mean survival was 12.5 months (0-43) in PEC and 26.55 (0-96) in MEC. Disease-free time in PEC and MEC was 5 months (0-37) and 10.25 (0-70) respectively. Only one patient achieved 5-year survival. CONCLUSION: Epidermoid carcinoma both plain and mixed is an aggressive tumour with poor prognosis and short survival. 100% PECs in our series are invasive at diagnosis, and no statistically significant differences were found in survival and disease-free time between both histological variants. Cystectomy remains the choice therapy.