Comparative outcomes assessment of uterine grade 3 endometrioid, serous, and clear cell carcinomas

The objective of this study is to assess effects of clinicopathologic risk factors and contemporary therapeutic interventions on high-risk uterine epithelial carcinoma outcomes.

Patient-, disease-, and treatment-specific variables were annotated. Survival was estimated via the Kaplan-Meier method. Associations were evaluated with Cox proportional hazard regression and summarized using hazard ratios.

From 1999 through 2008, therapy with curative intent was initiated for 119 grade 3 endometrioid (G3EC), 211 serous (USC), and 40 clear cell (CCC) carcinomas. Although clinicopathologic risk factors varied among the histologic subtypes, overall survival (OS) did not differ statistically between subtypes (P=.10) or in stage-for-stage comparative analyses (stage I/II, P=.45; stage III, P=.46; stage IV, P=.65). The 5-year cause-specific survival in stage I/II was 84.8%, 89.8%, and 83.9% for G3EC, USC, and CCC, respectively; multivariable modeling identified lymphovascular space involvement (LVSI) as the only independent prognostic factor (P=.02). For stage III, 5-year OS was 49.2% and 40.0% for G3EC and USC, respectively; multivariable modeling identified age (P<.001), LVSI (P<.001), unresectable nodal disease (P=.03), and regional radiotherapy (P=.01) as independent prognostic factors. For stage IV, 5-year OS was 8.7% and 12.1% for G3EC and USC, respectively; multivariable modeling identified LVSI (P=.002), cervical stromal invasion (P=.02), and adjuvant chemotherapy (P=.02) but not residual disease as independent prognostic factors.

When controlled for disease stage, outcomes did not differ among high-risk histologic subtypes. LVSI was a significant adverse prognostic factor within all stages. The lack of improved outcomes with contemporary therapy suggests that more innovative therapeutic approaches should be given higher priority.