Predictors of Response Following Neoadjuvant Cisplatin-Based Chemotherapy for Muscle Invasive Urothelial Bladder Cancer Using Molecular Profile: A Prospective Clinical Study.

OBJECTIVES:To predict response of patients with muscle invasive bladder cancer (MIBC) to neoadjuvant chemotherapy (NAC) through analysis of molecular profile assessed clinically (radiologically and by pathological examination of transurethral resection biopsy [TURBT] specimens) and definitively with histopathological examination after radical cystectomy (RC). METHODS:In a prospective study, tumor biopsies were obtained from patients with urothelial MIBC (T2-4a N0-2 M0) during TURBT. Patients were eligible for RC received 4 cycles of cisplatin-based NAC. DNA repair genes (BRACA1, ERCC1) & CTR gene m-RNA expression levels were assessed in resected tissue. The response to chemotherapy was assessed clinically (radiologically & TURBT) following NAC. Response was re-assessed for 64 patients who underwent RC and predictors of cancer-free survival (CFS) were calculated. Receiver operating characteristic (ROC) curve was used to delineate cutoff value copes with the best sensitivity and specificity for prediction of response to NAC. RESULTS:The study included 104 patients, 42 (40.4%) responded well to NAC clinically. Out of 64 patients who underwent RC, 26 (40.6%) showed good response to NAC. CFS at 18 months for patients who underwent RC was 60%. Statistical analysis showed that molecular profile was an independent predictor of good response to NAC both clinically and pathologically and also predicted better CFS. CONCLUSION:Molecular profile could play a decisive role in early detection of patients with MIBC who will get benefit from preoperative NAC.