Selecting the Best Candidates for Cisplatin-based Adjuvant Chemotherapy After Radical Cystectomy Among Patients with pN+ Bladder Cancer.

A trend towards greater benefit from adjuvant chemotherapy (ACT) in pN+ bladder cancer (BCa) has been observed in multiple randomized controlled trials. However, it is still unclear which patients might benefit the most from this approach. We retrospectively analyzed a multicenter cohort of 1381 patients with pTany pN1-3 cM0 R0 urothelial BCa treated with radical cystectomy (RC) with or without cisplatin-based ACT. The main endpoint was overall survival (OS) after RC. We performed 1:1 propensity score matching to adjust for baseline characteristics and conducted a classification and regression tree (CART) analysis to assess postoperative risk groups and Cox regression analyses to predict OS. Overall, 391 patients (28%) received cisplatin-based ACT. After matching, two cohorts of 281 patients with pN+ BCa were obtained. CART analysis stratified patients into three risk groups: favorable prognosis (≤pT2 and positive lymph node [PLN] count ≤2; odds ratio [OR] 0.43), intermediate prognosis (≥pT3 and PLN count ≤2; OR 0.92), and poor prognosis (pTany and PLN count ≥3; OR 1.36). Only patients with poor prognosis benefitted from ACT in terms of OS (HR 0.51; p < 0.001). We created the first algorithm that stratifies patients with pN+ BCa into prognostic classes and identified patients with pTany BCa with PLN ≥3 as the most suitable candidates for cisplatin-based ACT. PATIENT SUMMARY: We found that overall survival among patients with bladder cancer and evidence of lymph node involvement depends on cancer stage and the number of positive lymph nodes. Patients with more than three nodes affected by metastases seem to experience the greatest overall survival benefit from cisplatin-based chemotherapy after bladder removal. Our study suggests that patients with the highest risk should be prioritized for cisplatin-based chemotherapy after bladder removal.