Prospective Cohort Study of Pre- and Post-Diagnosis Obesity and Endometrial Cancer Survival.

BACKGROUND Disease-free and overall survival associations with anthropometric measures of obesity and changes in these exposures remain unknown among endometrial cancer survivors. METHODS Endometrial cancer survivors diagnosed between 2002-2006 completed direct anthropometric measurements and self-reported lifetime weight history during in-person interviews approximately 4 months after diagnosis (peri-diagnosis) and approximately 3 years after diagnosis (follow-up). Participants were followed until death or March 20, 2019. Cox proportional regression estimated multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) for body mass index (BMI), weight, waist circumference, and waist-hip ratio with disease-free survival (DFS) and overall survival (OS). Statistical tests were two-sided. RESULTS 540 and 425 cancer survivors were assessed peri-diagnosis and follow-up, respectively. During the median 14.2 years of follow-up (range = 0.3-16.5 years), 132 participants had a recurrence and/or died (DFS) with 111 deaths overall (OS). Reduced DFS was noted with greater recalled weight one-year before-diagnosis (HR = 1.88, 95% CI = 1.15 to 3.07), BMI one-year before-diagnosis (HR = 1.88, 95% CI = 1.09 to 3.22), and measured peri-diagnosis BMI (HR = 2.04, 95% CI = 1.18 to 3.53). Measured peri-diagnosis waist circumference ≥88 cm was associated with decreased DFS (HR = 1.94, 95% CI = 1.24 to 3.03) and OS (HR = 1.90, 95% CI = 1.16 to 3.13). A two-fold decrease in DFS and OS was associated with ≥5% BMI or weight change from one-year before diagnosis to peri-diagnosis. No associations were observed for the assessment during follow-up. CONCLUSION One-year before- and peri-diagnosis anthropometric measures of obesity were associated with reduced survival among endometrial cancer survivors. Anthropometric changes from one-year before- to peri-diagnosis may provide an important indication of future survival in this population.