Optimal Number of Cycles of First-line Platinum-based Chemotherapy for Metastatic Urothelial Carcinoma

Abstract

Background/aim: In recent years, switch maintenance after platinum-based chemotherapy has been a standard of care. However, the appropriate number of systemic chemotherapy cycles against advanced-stage urothelial carcinoma (UC) remains unclear. This study assessed the survival outcomes of first-line platinum-based chemotherapy according to treatment cycles in patients with metastatic disease.

Patients and methods: We retrospectively evaluated patients with metastatic bladder and upper urinary tract cancer who received platinum-based combination therapy. Overall survival (OS) was evaluated using the Kaplan-Meier method and the log-rank test.

Results: Of 179 patients, 47 (26.3%) were women, and 73 (40.8%) had upper urinary tract cancer. Furthermore, 47 (26.3%) who were not eligible for cisplatin received carboplatin. The median number of treatment cycles was 3 (range=1-14 cycles). The rates of progressive disease within two cycles, from two to four cycles, and from four to six cycles were 18.4%, 19.2%, and 30.6%, respectively. The median OS of patients with 2, 3, 4, 5-6, and ≥7 treatment cycles were 8.6, 14.3, 21.3, 24.4, and 26.1 months, respectively. The OS did not significantly differ between patients receiving four treatment cycles and those receiving ≥5 treatment cycles. In patients with disease control (complete or partial response or stable disease) receiving ≥4 treatment cycles, there was no significant difference in terms of OS between patients receiving four cycles and those receiving six cycles.

Conclusion: Four cycles of first-line platinum-based chemotherapy can be effective in patients with metastatic UC.

Keywords: Urothelial carcinoma; avelumab; carboplatin; chemotherapy; cisplatin; number of cycles; switch maintenance.