Adherence to the WCRF/AICR Cancer Prevention Recommendations and Risk of Recurrence in Non-muscle Invasive Bladder Cancer

OBJECTIVES: Patients with cancer are recommended to follow cancer prevention guidelines due to insufficient evidence for specific recommendations for cancer survivors. It is unclear if adherence to these recommendations lowers risk of recurrence among patients with non-muscle invasive bladder cancer (NMIBC). We examined whether the standardized lifestyle score measuring adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention recommendations was associated with risk of recurrence among NMIBC patients. METHODS: The study population included 979 patients newly diagnosed with NMIBC between 2014 and 2017 from the prospective cohort UroLife. Lifestyle was assessed shortly after diagnosis (reflecting the prediagnosis period) and 3 months postdiagnosis. The standardized 2018 WCRF/AICR score was constructed based on recommendations for BMI, physical activity, diet, and alcohol intake. We computed multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazard regression models. RESULTS: Median follow-up time was 3.7 years and 315 first recurrences were observed. Patients with the highest versus lowest postdiagnosis WCRF/AICR scores had a statistically non-significant 23% lower risk of recurrence (HR 0.77, 95%CI: 0.53, 1.11). The same tendency was observed for the diet and alcohol sub-scores. No inverse associations were observed for the BMI or physical activity sub-scores and for the WCRF/AICR score at diagnosis. Each 1-point improvement in the WCRF/AICR score after diagnosis seemed to be associated with a lower recurrence risk (HR 0.86; 95% CI: 0.72, 1.01). CONCLUSIONS: Greater adherence to the WCRF/AICR cancer prevention recommendations and improvements therein after NMIBC diagnosis might be associated with a decreased recurrence risk. As a next step, we will extend our Cox models to include multiple recurrences which will improve the statistical power of our analyses. FUNDING SOURCES: World Cancer Research Fund International.