Survival and oncologic outcomes of complete transurethral resection of bladder tumor prior to neoadjuvant chemotherapy for muscle-invasive bladder cancer

Abstract

Objectives: Prior studies have shown that pathologic complete response at radical cystectomy, a significant prognostic factor, can be attributed to both neoadjuvant chemotherapy (NAC) and high-quality transurethral resections (TURBT) prior to NAC. It remains unclear whether the visual completeness of TURBT prior to NAC plays an important role in subsequent outcomes. We sought to assess the association of completeness of TURBT prior to NAC with response and survival outcomes.

Methods and materials: We retrospectively reviewed all patients with clinically localized muscle-invasive bladder cancer at our institution who received NAC from 2000 to 2017. Complete TURBT was defined as resection of all visible tumor in entirety, resection to normal-appearing muscle, and/or repeat pre-NAC TURBT revealing cT0. Patients who were restaged as cT0 after NAC and refused cystectomy were placed on an active surveillance/delayed intervention (ASDI) protocol. The primary endpoints were overall and cancer-specific survival. The secondary endpoints were recurrence-free and muscle-invasive recurrence-free survival.

Results: Of 93 patients, 62 (67%) underwent complete TURBT prior to chemotherapy. Compared to patients with incomplete TURBT, those with complete TURBT had lower rates of variant histology (13% vs. 32%) and hydronephrosis (15% vs. 39%). Also, 36% of patients with incomplete TURBT had ≥cT3 disease prior to NAC, compared to none in the complete TURBT cohort. Patients with complete TURBT were more likely to defer RC and pursue ASDI (61% vs. 32%). Those with complete TURBT had lower rates of pT2 or higher disease at cystectomy (48% vs. 75%), with a lower rate of N+ disease trending towards significance (17% vs. 37%). Patients with complete TURBT had higher 5-year overall (77% vs. 46%, P = 0.003) and cancer-specific (85% vs. 50%, P = 0.001) survival. On Cox regression analysis, complete TURBT was significantly associated with superior cancer-specific, recurrence-free, and muscle-invasive recurrence-free survival.

Conclusions: A complete TURBT prior to NAC is associated with improved survival and oncologic outcomes in this cohort with muscle-invasive bladder cancer. The extent to which complete TURBT simply represents a proxy for less aggressive disease or is actually a beneficial therapeutic intervention which improves response to chemotherapy is difficult to define retrospectively.

Keywords: Cystectomy; Neoadjuvant therapy; Recurrence; Survival analysis; Urinary bladder neoplasms.