Carboplatin based induction chemotherapy for nonorgan confined bladder cancer--a reasonable alternative for cisplatin unfit patients?

Purpose: We investigated induction carboplatin based chemotherapy in patients with nonorgan confined urothelial carcinoma who were considered unfit for cisplatin. A comparison was made with patients who received induction cisplatin based combination chemotherapy.

Materials and methods: We identified 167 patients with nonorgan confined urothelial carcinoma who received induction cisplatin based combination chemotherapy (126) or gemcitabine and carboplatin (41) at our hospital between 1990 and 2010. Of the patients 124 completed 4 cycles of cisplatin based combination chemotherapy or gemcitabine and carboplatin. Clinical response (ycTNM) was evaluated according to RECIST (Response Evaluation Criteria in Solid Tumors) 1.1. Radical cystectomy and bilateral extended pelvic lymph node dissection were performed in 106 patients. A pathological complete response was defined as no evidence of disease (ypT0N0). Disease specific survival was analyzed using the Kaplan-Meier method. Multivariate analysis was performed.

Results: Complete clinical response rates did not differ significantly among the treatment groups. A pathological complete response was seen in 33.7% of specimens in the cisplatin based combination chemotherapy group vs 30.3% in the gemcitabine and carboplatin group (p = 0.808). We found no significant difference in disease specific survival between patients who started cisplatin based combination chemotherapy and those who started gemcitabine and carboplatin. For patients who completed 4 cycles and underwent radical cystectomy there was also no significant difference in disease specific survival between the groups. On multivariate analysis a pathological complete response was the only variable significantly associated with disease specific survival (p <0.045).

Conclusions: Induction gemcitabine and carboplatin for nonorgan confined urothelial carcinoma achieves clinical and pathological response rates, and survival outcomes comparable to those of the cisplatin based combination chemotherapy schemes. Our data suggest that a carboplatin based regimen can be considered a reasonable alternative for cisplatin unfit patients in the preoperative setting.