Prospective cohort study of metabolic syndrome and endometrial cancer survival

Comorbidities are known to increase endometrial cancer risk, but the separate and combined impact of these risk factors on endometrial cancer survival remains unclear. This study aimed to determine the associations between metabolic syndrome and its components with disease-free survival, overall survival, endometrial cancer-specific survival and recurrence among endometrial cancer survivors.

Cases from a population-based case-control study who were diagnosed with primary endometrial cancer between 2002 and 2006 in Alberta, Canada were followed until death or March 20, 2019. Baseline in-person interviews, direct anthropometric measurements and fasting blood samples were used to assess metabolic syndrome (presence of ≥3 of the following: waist circumference ≥ 88 cm, fasting blood glucose ≥100 mg/dL, triglycerides ≥150 mg/dL, high-density lipoprotein cholesterol <50 mg/dL and self-reported hypertension). Cox proportional hazards regression and Fine and Gray competing risk models were used to estimate multivariate-adjusted hazard ratios (95% CI) for these associations.

Among 540 endometrial cancer survivors, 325 had metabolic syndrome at diagnosis and 132 had a recurrence and/or died during the median 14.2 years of follow-up (range: 0.3-16.5 years). In multivariable analyses, being diagnosed with metabolic syndrome (HR = 1.98, 95% CI = 1.07-3.67) and having an elevated waist circumference (≥88 cm; HR = 2.12, 95% CI = 1.18-3.80; HR_{per 5 cm} = 1.21, 95% CI = 1.07-1.36) were associated with worse overall survival. Additionally, increasing waist circumference (per 5 cm) was also associated worse with disease-free survival (HR_{per 5 cm} = 1.11, 95% CI = 1.00-1.24).

The metabolic syndrome, in particular central adiposity, were associated with worse overall and disease-free survival in endometrial cancer survivors.