Excision repair cross-complementing 1 (ERCC1) and survival in advanced bladder cancer: Confirmatory results using immunohistochemistry

5025 Background: DNA damaging agents are the backbone of combination chemotherapy regimens for the treatment of advanced bladder cancer. We hypothesized that levels of DNA repair genes such as ERCC1 could predict survival in patients receiving platinum based therapy. Our previous work (Bellmunt J et al, Ann Oncol. 2007) showed that survival was significantly higher in advanced bladder cancer patients with low gene expression levels of ERCC1 measured by RT-qPCR (25.4 versus 15.4 months; p = 0.03). We aimed to confirm these findings using immunohistochemistry (IHC) in an independent cohort of advanced bladder cancer patients treated with cisplatin-based chemotherapy at our institution. Methods: Formalin-fixed paraffin-embedded tumor tissue was available from 51 patients. IHC stains for ERCC1 protein levels were scored as percentage and intensity of positive cells. ERCC1 staining was considered positive if detected in ≥1% tumor cells. The Kaplan-Meier method was used to calculate survival and the Cox proport...