Abstract 5323: Obesity and ovarian cancer survival revisited

Abstract

Abstract Research on the impact of obesity on ovarian cancer survival is inconsistent but previous studies did not consider the possible impact of ascites, bowel obstruction, or cachexia, which commonly occur in late-stage disease. We evaluated this association in a cohort study of primary invasive epithelial ovarian cancers diagnosed from 2000-2013 in Kaiser Permanente Northern California (KPNC) (n=1,157). Deaths were identified through December 2014, with median follow-up of 37 months. Proportional hazards regression was used to estimate overall and ovarian cancer-specific mortality, accounting for prognostic variables including age at diagnosis, race, stage, grade, histology, comorbidities, treatment, post-treatment CA125 levels, ascites, and bowel obstruction. There was no evidence of an association between BMI and overall or ovarian cancer-specific survival. However, we found strong effect modification by stage (Pinteraction<.01). Compared to normal pre-diagnosis BMI (18.5-24.9 kg/m2), for women who were obese before diagnosis (BMI≥35 kg/m2) risk of ovarian cancer-specific mortality was increased among those diagnosed at stages I/II (Hazard ratio [HR]: 3.40; 95% confidence interval [CI]: 1.16-9.99), but reduced among those diagnosed with stage IV disease (HR: 0.58; 95%CI: 0.35-0.96). Associations persisted after excluding those diagnosed with cachexia (n=91) and further adjusting for ascites and bowel obstruction, with no evidence of effect modification by these factors. Associations of obesity with ovarian cancer survival differ by stage, with decreased survival among those with localized disease and increased survival among those with late-stage disease. Stage-specific effects of obesity on survival suggest a tailored approach to improve prognosis may be appropriate. Citation Format: Elisa V. Bandera, Valerie Lee, Bo Qin, Lorna Rodriguez, Bethan Powell, Lawrence H. Kushi. Obesity and ovarian cancer survival revisited [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5323. doi:10.1158/1538-7445.AM2017-5323