Mertens, Laura S

Objective To validate International Bladder Cancer Group (IBCG) definitions of Bacillus Calmette‐Guérin (BCG)‐unresponsive and BCG‐exposed non‐muscle‐invasive bladder cancer (NMIBC) and assess prognostic heterogeneity across various BCG‐failure types. Patients and Methods From a multicentre international cohort of 3806 BCG‐treated patients, 591 who developed high‐grade NMIBC recurrence following BCG between 2003 and 2024 were included. Progression‐free survival (PFS) was the primary endpoint; cancer‐specific (CSM) and overall mortality (OM) were secondary endpoints. Cumulative incidence functions, competing‐risk models and multivariable Cox regression were used. Results Patients with BCG‐unresponsive and BCG‐exposed disease showed similar PFS, CSM, and OM (all P > 0.05). When stratified into five subgroups, prognosis varied: 5‐year progression rates were 29% for BCG‐unresponsive, 32.5% for late relapse (between 6 and 24 months) after adequate BCG, 30% for BCG‐exposed with inadequate BCG (<24 months from induction), 6.2% for BCG‐resistant, and 14% for very late relapse (>24 months since last BCG) ( P < 0.01). In multivariable analysis, BCG‐exposed after inadequate BCG (subdistribution hazard ratio [sHR] 3.42, 95% confidence interval [CI] 1.33–8.84), late relapse (sHR 3.74, 95% CI 1.59–8.78), and BCG‐unresponsive (sHR 2.34, 95% CI 1.00–5.44) were associated with higher progression risks compared to very late relapse. Limitations include retrospective design and treatment heterogeneity. Conclusions Under IBCG definitions, BCG‐unresponsive and BCG‐exposed NMIBC have similarly poor outcomes. A refined classification reveals prognostic heterogeneity, with late relapses after adequate BCG demonstrating outcomes comparable to BCG‐unresponsive, and very late relapses conferring better prognosis.

Objective To investigate the optimal number of induction chemotherapy cycles needed to achieve a pathological response in patients with clinically lymph node‐positive (cN+) bladder cancer (BCa) who received three or four cycles of induction chemotherapy followed by consolidative radical cystectomy (RC) with pelvic lymph node dissection. Patients and Methods We included 388 patients who received three or four cycles of cisplatin/gemcitabine or (dose‐dense) methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC), followed by consolidative RC for cTanyN1–3M0 BCa. We compared pathological complete (pCR = ypT0N0) and objective response (pOR = yp ≤T1N0) between treatment groups. Predictors of pCR and/or pOR were assessed using uni‐ and multivariable logistic regression analysis. The secondary endpoints were overall (OS) and cancer‐specific survival (CSS). We evaluated the association between the number of induction chemotherapy cycles administered and survival outcomes on multivariable Cox regression. Results Overall, 101 and 287 patients received three or four cycles of induction chemotherapy, respectively. Of these, 72 (19%) and 128 (33%) achieved pCR and pOR response, respectively. The pCR (20%, 18%) and pOR (40%, 31%) rates did not differ significantly between patients receiving three or four cycles ( P > 0.05). The number of cycles was not associated with pCR or pOR on multivariable logistic regression analyses. The 2‐year OS estimates were 63% (95% confidence interval [CI] 0.53–0.74) and 63% (95% CI 0.58–0.7) for patients receiving three or four cycles, respectively. Receiving three vs four cycles was not associated with OS and CSS on uni‐ or multivariable Cox regression analyses. Conclusion Pathological response and survival outcomes did not differ between administering three or four induction chemotherapy cycles in patients with cN+ BCa. A fewer cycles (minimum three) may be oncologically sufficient in patients with cN+ BCa, while decreasing the wait for definitive local therapy in those patients who end up without a response to chemotherapy. This warrants further validation.