Influence of Comorbidity on the Risk of Death: A Single Institution Study of 1132 Women With Early-stage Uterine Cancer.

Abstract

The impact of competing medical comorbidity on survival endpoints in women with early stage endometrial carcinoma (EC) is not well studied. The study goal was to utilize a validated comorbidity scoring system to determine its impact on all-cause mortality as well as on recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS) in patients with early-stage EC. For this IRB-approved study, we reviewed our prospectively maintained uterine cancer database of 1720 patients. We identified 1132 patients with EC FIGO stages I-II who underwent hysterectomy from 1984 to 2011. Age-adjusted Charlson Comorbidity Index (AACCI) at time of hysterectomy was retrospectively calculated by physician chart review. The cause of death (uterine cancer-related and unrelated) was correlated with AACCI. Univariate and multivariate modeling with Cox regression analysis was used to determine significant predictors of OS, DSS, and RFS. The Kaplan-Meier and the log-rank test methods were used to evaluate survival outcomes. After a median follow-up of 51 months, 262 deaths were recorded (42 from EC [16%], and 220 [84%] from other causes). Median AACCI score for the study cohort was 3 (range, 0 to 15). On the basis of AACCI, patients were grouped as follows: 0 to 2 (group 1, n=379), 3 to 4 (group 2, n=532), and ≥5 (group 3, n=221). By AACCI grouping, the 5-year RFS, DSS, and OS were 95%, 98%, and 97% for group 1, 89%, 95%, and 87% for group 2, and 86%, 95% and 72% for group 3 (P<0.0001). The cause of death in the first 10 years after hysterectomy in our study was mainly non-uterine cancer-related (78% vs. 22% for uterine cancer-related) causes. On multivariate analyses, higher AACCI, lymphovascular space invasion (LVSI), higher tumor grade, age, and involvement of the lower uterine segment were significant predictors of shorter OS. On multivariate analysis for DSS and RFS, only high tumor grade and LVSI were significant predictors. The cause of death for women with early stage EC is mainly nonuterine cancer-related. Comorbidity score is a significant predictor of OS in our study cohort. Comorbidity scores may be useful as a stratification factor in any prospective clinical trial for women with early-stage EC.