We assessed the clinical significance of squamous differentiation (SD) of urothelial carcinoma (UC) in patients who receive radical cystectomy for locally invasive bladder cancer. Patients with urothelial carcinoma with squamous differentiation (UCSD) had a poor pathologic response to neoadjuvant chemotherapy compared with those with pure UC. SD was an independent predictor for disease-free survival and overall survival in locally invasive bladder cancer.Objective:
The efficacy of chemotherapy on UCSD is not known. This study was conducted to investigate the efficacy of cisplatin-based chemotherapy and prognosis of patients with UC with or without SD of the bladder.Methods:
Patients with invasive bladder cancer (clinical T3-4aN0M0) who were treated between March 2003 and March 2015 with 2 or 3 cycles of neoadjuvant chemotherapy followed by radical cystectomy were retrospectively evaluated. Treatment outcomes were compared for each pathologic type in UCSD and pure UC. The primary end point was pathologic response in the cystectomy specimens. Disease-free survival and overall survival were secondary end points.Results:
We evaluated 9 patients with UCSD and 29 patients with pure UC. In the cystectomy specimens, pathologic complete response without residual tumors was not seen in any patients with UCSD, but evident in 10 patients (34.5%) with pure UC. The proportion of pathologic downstaging was significantly lower in patients with UCSD than in those with pure UC (11.1% vs. 51.7%; P = .031). Patients with UCSD had poorer disease-free survival (P < .001) and overall survival (P = .001) than those with pure UC. On multivariate Cox regression analysis, SD in UC was an independent predictor of recurrence (hazard ratio, 4.43; 95% confidence interval, 1.44-13.6, P = .009) and mortality (hazard ratio, 3.51; 95% confidence interval, 1.11-11.1, P = .032).Conclusions:
UCSD of the bladder is less sensitive to cisplatin-based chemotherapy and has poor prognosis.