Neutrophil-to-lymphocyte ratio as a bladder cancer biomarker: Assessing prognostic and predictive value in SWOG 8710.

BACKGROUND: Risk stratification is a major challenge in bladder cancer (BC), and a biomarker is needed. Multiple studies have reported the neutrophil-to-lymphocyte ratio (NLR) as a promising candidate; however, these analyses have methodological limitations. Therefore, the authors performed a category B biomarker study to test whether NLR is prognostic for overall survival (OS) after curative treatment or is predictive for the survival benefit from neoadjuvant chemotherapy (NAC). METHODS: This study is an unplanned secondary analysis of SWOG 8710, a randomized phase 3 trial that assessed cystectomy with or without NAC in 317 patients with muscle-invasive BC. NLR was calculated from prospectively collected complete blood counts. For the prognostic analysis, 230 patients were identified; for the predictive analysis, 263 were identified. NLR was evaluated with proportional hazards models including prespecified factors (age, sex, T-stage, lymphovascular invasion, and treatment arm). RESULTS: With a median follow-up of 18.6 years, there were 172 and 205 deaths in the prognostic and predictive cohorts, respectively. In a multivariable analysis, NLR was not prognostic for OS (hazard ratio [HR], 1.04; 95% confidence interval [CI], 0.98-1.11; P = .24). Furthermore, NLR did not predict for the OS benefit from NAC (HR, 1.01; 95% CI, 0.90-1.14; P = .86). Factors associated with worse OS were older age (HR, 1.05; 95% CI, 1.04-1.07; P < .001) and surgery without NAC (HR, 1.39; 95% CI, 1.03-1.88; P = .03). CONCLUSIONS: This is the first analysis of NLR in BC to use prospectively collected clinical trial data. In contrast to previous studies, it suggests that NLR is neither a prognostic nor predictive biomarker for OS in muscle-invasive BC. Cancer 2017;123:794-801. © 2016 American Cancer Society.

Validating a Local Failure Risk Stratification for Use in Prospective Studies of Adjuvant Radiation Therapy for Bladder Cancer.

PURPOSE: To inform prospective trials of adjuvant radiation therapy (adj-RT) for bladder cancer after radical cystectomy, a locoregional failure (LF) risk stratification was proposed. This stratification was developed and validated using surgical databases that may not reflect the outcomes expected in prospective trials. Our purpose was to assess sources of bias that may affect the stratification model's validity or alter the LF risk estimates for each subgroup: time bias due to evolving surgical techniques; trial accrual bias due to inclusion of patients who would be ineligible for adj-RT trials because of early disease progression, death, or loss to follow-up shortly after cystectomy; bias due to different statistical methods to estimate LF; and subgrouping bias due to different definitions of the LF subgroups. METHODS AND MATERIALS: The LF risk stratification was developed using a single-institution cohort (n=442, 1990-2008) and the multi-institutional SWOG 8710 cohort (n=264, 1987-1998) treated with radical cystectomy with or without chemotherapy. We evaluated the sensitivity of the stratification to sources of bias using Fine-Gray regression and Kaplan-Meier analyses. RESULTS: Year of radical cystectomy was not associated with LF risk on univariate or multivariate analysis after controlling for risk group. By use of more stringent inclusion criteria, 26 SWOG patients (10%) and 60 patients from the single-institution cohort (14%) were excluded. Analysis of the remaining patients confirmed 3 subgroups with significantly different LF risks with 3-year rates of 7%, 17%, and 36%, respectively (P<.01), nearly identical to the rates without correcting for trial accrual bias. Kaplan-Meier techniques estimated higher subgroup LF rates than competing risk analysis. The subgroup definitions used in the NRG-GU001 adj-RT trial were validated. CONCLUSIONS: These sources of bias did not invalidate the LF risk stratification or substantially change the model's LF estimates.

Optimizing bladder cancer locoregional failure risk stratification after radical cystectomy using SWOG 8710.

BACKGROUND: Clinical trials of radiation after radical cystectomy (RC) and chemotherapy for bladder cancer are in development, but inclusion and stratification factors have not been clearly established. In this study, the authors evaluated and refined a published risk stratification for locoregional failure (LF) by applying it to a multicenter patient cohort. METHODS: The original stratification, which was developed using a single-institution series, produced 3 subgroups with significantly different LF risk based on pathologic tumor (pT) classification and the number of lymph nodes identified. This model was then applied to patients in Southwest Oncology Group (SWOG) 8710, a randomized trial of RC with or without chemotherapy. LF was defined as any pelvic failure before or within 3 months of distant failure. RESULTS: Patients in the development cohort and the SWOG cohort had significantly different baseline characteristics. The original risk model was not fully validated in the SWOG cohort, because lymph node yield was not as strongly associated with LF as in the development cohort. Regression analysis indicated that margin status could improve the model. A revised stratification using pT classification, margin status, and the number of lymph nodes identified produced 3 subgroups with significantly different LF risk in both cohorts: low risk (≤pT2), intermediate risk (≥pT3 with negative margins AND ≥10 lymph nodes identified), and high risk (≥pT3 with positive margins OR <10 lymph nodes identified) with 5-year LF rates of 8%, 20%, and 41%, respectively, in the SWOG cohort and 8%, 19%, and 41%, respectively, in the development cohort. CONCLUSIONS: A model incorporating pT classification, margin status, and the number of lymph nodes identified stratified LF risk in 2 different RC populations and may inform the design of future trials.