Second-line single-agent versus doublet chemotherapy as salvage therapy for metastatic urothelial cancer: a systematic review and meta-analysis.

The efficacy and safety of a combination of chemotherapeutic agent compared with single-agent chemotherapy in the second-line setting of advanced urothelial carcinoma (UC) are unclear. We aimed to study the survival impact of single-agent compared with doublet chemotherapy as second-line chemotherapy of advanced UC.