DeWees, Todd A

AbstractBackgroundLocal‐regional failure (LF) for locally advanced bladder cancer (LABC) after radical cystectomy (RC) is common even with chemotherapy and is associated with high morbidity/mortality. Postoperative radiotherapy (PORT) can reduce LF and may enhance overall survival (OS) but has no defined role. We hypothesized that the addition of PORT would improve OS in LABC in a large nationwide oncology database.MethodsWe identified ≥ pT3pN0‐3M0 LABC patients in the National Cancer Database diagnosed 2004‐2014 who underwent RC ± PORT. OS was calculated using Kaplan‐Meier and Cox proportional hazards regression modeling was used to identify predictors of OS. Propensity matching was performed to match RC patients who received PORT vs those who did not.Results15,124 RC patients were identified with 512 (3.3%) receiving PORT. Median OS was 20.0 months (95% CI, 18.2‐21.8) for PORT vs 20.8 months (95% CI, 20.3‐21.3) for no PORT (P = 0.178). In multivariable analysis, PORT was independently associated with improved OS: hazard ratio 0.87 (95% CI, 0.78‐0.97); P = 0.008. A one‐to‐three propensity match yielded 1,858 patients (24.9% receiving PORT and 75.1% without). In the propensity‐matched cohort, median OS was 19.8 months (95% CI, 18.0‐21.6) for PORT vs 16.9 months (95% CI, 15.6‐18.1) for no PORT (P = 0.030). In the propensity‐matched cohort of urothelial carcinoma patients (N = 1,460), PORT was associated with improved OS for pT4, pN+, and positive margins (P < 0.01 all).ConclusionIn this observational cohort, PORT was associated with improved OS in LABC. While the data should be interpreted cautiously, these results lend support to the use of PORT in selected patients with LABC, regardless of histology. Prospective trials of PORT are warranted.

AbstractBackgroundThis study evaluates the prognostic significance of 18F‐fluorodeoxyglucose‐positron emission tomography ([F‐18]FDG‐PET)‐derived metabolic tumor volume (MTV) in human papillomavirus (HPV)‐associated oropharyngeal squamous cell carcinomas (OPSCCs) in the context of AJCC 8th edition staging.MethodsWe performed a retrospective study of HPV‐associated OPSCCs treated with postoperative or definitive radiation. The prognostic significance of pretreatment MTV for freedom from recurrence (FFR), freedom from distant metastasis (FFDM), and overall survival (OS) was determined using Kaplan‐Meier analysis. Multivariate analysis (MVA) was performed using Cox regression.ResultsIn this 153‐patient cohort, stratifying by the optimum MTV (24 cm3) was prognostic for FFR (P = .0002), FFDM (P = .001), and OS (P < .0001). Metabolic tumor volume (MTV) was prognostic of FFR in AJCC 8th edition stage I/II (P = .03), and stage III patients (P = .04). On multivariate analysis only MTV was a significant factor for OS.ConclusionMetabolic tumor volume (MTV) is a significant prognostic factor in HPV‐associated OPSCCs, independent of AJCC 8th edition stage.