Squamous Differentiation Predicts Poor Response to Cisplatin-Based Chemotherapy and Unfavorable Prognosis in Urothelial Carcinoma of the Urinary Bladder.

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.