The impact of age and stage on the competing risk of cancer-related and non-cancer death in low- or high-grade endometrioid endometrial carcinoma and uterine serous carcinoma

Abstract

Objectives: To estimate the impact of age and stage on the risk of cancer-related death (CRD) and non-cancer death (NCD) in women with low grade (LG)-endometrioid endometrial carcinoma (EEC) relative to high grade (HG)-EEC or uterine serous carcinoma (USC). Methods: Women diagnosed between 1988-2016 with stage I-IV LG-EEC (grade 1 or 2), HG-EEC (grade 3) or USC in the 18-region Surveillance, Epidemiology, and End Results registry were evaluated. Patients missing survival data or with multiple malignancies were excluded. Fine and Gray's sub-distribution hazards method was applied to evaluate the impact of age and stage on the competing risk of death in LG-EEC, HG-EEC or USC. Results: There were 121,028 eligible patients including 77.4% with LG-EEC, 14.8% with HG-EEC, and 7.8% with USC. The median age at diagnosis was 5 or 7 years older in women with HG-EEC or USC relative to LG-EEC, respectively. The proportion diagnosed with stage I vs stage IV disease varied by histology with 85.5% vs 2.3% with LG-EEC, 54.2% vs 17.0% with HG-EEC and 37.5% vs 30.1% with USC, respectively. CRD rates plateaued after 4 years whereas NCD rates continued to increase through 10 years from diagnosis across the histologic subtypes (Fig. 1A). The 5-year CRD rate increased incrementally by histology (5.7% with LG-EEC, 32.6% with HG-EEC or 51.2% with USC), older age (6.1% in Conclusions: Integration of age, stage and histology enhances the prediction of CRD and NCD risks for endometrial cancer patients. This comparison allows for enhanced personalization of cancer care and prioritized treatment of comorbid conditions, particularly when CRD risk is low. CRD risk increased dramatically over the first 4 years from diagnosis with higher stage than with older age and was incrementally higher in HG-EEC and USC relative to LG-EEC. Risk of NCD increased with age over 10-years from diagnosis but not by histology or stage.