Abstract 1755: Weight change, prostate cancer-specific mortality, and biochemical recurrence in a prospective cohort study of U.S. men

Abstract

Abstract Obesity is associated with an increased risk of fatal prostate cancer. However, the relevant timing of obesity for risk has not been established, and the impact of weight change on prognosis has been understudied. We prospectively investigated the association between weight change and obesity with prostate cancer outcomes among 5,173 men diagnosed with prostate cancer (clinical TNM-stage <T3b) from 1986 to 2012 in the Health Professionals Follow-up Study. Men were followed for biochemical recurrence, development of distant metastasis, and mortality until 2014. Cox proportional hazards models were used to estimate hazard ratios for change in weight from age 21 to diagnosis and in the 4 years prior to diagnosis, adjusting for potential confounding by lifestyle and clinical factors. Because weight, weight change, and mortality are strongly associated with smoking, we conducted the analysis among all prostate cancer patients and among never smokers only (N = 2,554). Among all patients, weight gain from age 21 to the time of diagnosis was associated with risk of lethal prostate cancer (distant metastases or prostate cancer death). Compared to those with stable weight (±10 lbs) from age 21 to diagnosis, those who gained >30 lbs had a 1.44-fold higher risk of lethal cancer (95% CI 1.03-2.01, p-trend = 0.06, adjusting for lifestyle factors, stage, grade, PSA at diagnosis, and weight at age 21). Among never smokers, this association was stronger (HR 2.19, 95% CI 1.31-3.68, p-trend = 0.005). Weight gain in the 4 years preceding diagnosis was suggestively, but not significantly, associated with lethal cancer among never smokers (HR for >5 lbs gain vs stable weight [±5 lbs] 1.48, 95% CI, 0.96, 2.28). No significant associations were found between weight change and biochemical recurrence. Our findings suggest a positive association between adult weight gain and risk of lethal prostate cancer. Metabolic changes associated with weight gain may promote prostate cancer progression. Citation Format: Barbra Dickerman, Thomas Ahearn, Edward Giovannucci, Lorelei Mucci, Kathryn Wilson. Weight change, prostate cancer-specific mortality, and biochemical recurrence in a prospective cohort study of U.S. men. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1755.