Objectives The aim of this study was to evaluate the prevalence and types of medical morbidities in Thai endometrial cancer (EMC) patients and their impact on treatment outcomes.

Methods The EMC patients treated in the institution from 1995 to 2012 and with available medical history were identified. Data collected were age; medical morbidities; tumor stage, histopathology, and grade; adjuvant therapy; living status; and cause of death.

Results Of the 335 EMC patients included in the study, 77.3% had early-stage diseases, and 46.6% received adjuvant therapy. A total of 220 patients (65.7%) had medical morbidities. Median age of patients with medical morbidities was significantly higher than those without: 59 years (range, 30–84 years) versus 52 years (range, 30–86 years) (P < 0.001). One or more components of metabolic syndrome were the most common: 10.9% had all 4 components, 30.0% had three, and 31.4% had two. Thyroid dysfunction, as the second most common, was found in 8.2%. From a median follow-up of 56.5 months (0.07–234.04 months), 18.5% were dead: 11.6% from EMC, 4.8% from medical conditions, and 2.1% from other causes. Survival of the patients who had or had no medical morbidities was not significantly different: 5-year overall survival and 5-year cancer-specific survival were 84.7% (95% confidence interval [CI], 79.6%–89.8%) versus 84.0% (95% CI, 76.9%–91.0%) (P = 0.918) and 87.3% (95% CI, 82.6%–92.0%) versus 89.3% (95% CI, 83.2%–95.3%) (P = 0.986), respectively.

Conclusion This was the first large analysis in South-East Asia showing common incidence of medical morbidities in EMC patients. One or more components of metabolic syndrome were the most common. Some medical illnesses were the causes of death. Comprehensive and continual medical care for EMC patients is important.