Endometrial cancer in Asian and American Indian/Alaskan Native women: tumor characteristics, treatment and outcome compared to non-Hispanic white women

Gynecol Oncol. 2014 Feb;132(2):443-9. doi: 10.1016/j.ygyno.2013.11.028. Epub 2013 Dec 3.

Abstract

Objective: The objective of this study is to compare survival of Asian (AS), American Indian/Alaskan Native (AI/AN) and non-Hispanic white (NHW) women with endometrial adenocarcinoma (EC).

Methods: Patients with EC were identified from the Surveillance, Epidemiology, and End Results program from 1988 to 2009. Kaplan-Meier survival methods and Cox proportional hazards regression were performed.

Results: Of the 105,083 women, 97,763 (93%) were NHW, 6699 (6.4%) were AS and 621 (0.6%) were AI/AN. AS and AI/AN were younger than NHW with mean age of 57.7 and 56.5 vs. 64.3 years (p < 0.001 and 0.059). Advanced stage and high-risk histology were more prominent in AS than NHW (15.6% vs. 13.3%, p = 0.04, 10.6% vs. 9.6%, p= 0.041). Lymphadenectomy was performed more frequently in AS than NHW (56.7% vs. 48.2%, p < 0.001). Asian immigrants were younger than Asian natives (mean age 57 vs. 60.5 years, p < 0.001). In multivariate analysis, AS had better overall (OS) (HR 0.86, 95% CI 0.81-0.91, p < 0.001) and cancer-specific survival (CSS) (HR 0.92, 95% CI 0.84-1.00, p = 0.05) than NHW. Further, Asian immigrants had better OS (HR 0.83, 95% CI 0.73-0.94, p = 0.002) and CSS (HR 0.66, 95% CI 0.54-0.80, p < 0.001) than Asian natives. In contrast, AI/AN had worse OS (HR 1.35, 95% CI 1.15-1.59, p < 0.001) but no difference in CSS (HR 1.06, 95% CI 0.80-1.40, p = 0.69) than NHW.

Conclusions: Asians were younger at presentation, more likely to have lymphadenectomy and had an improved outcome compared to NHW. Interestingly, Asian immigrants had more favorable outcome than Asians born in the US. Further studies are warranted to find possible explanations for such a difference.

Keywords: Asian, American Indian/Alaskan Native, endometrial cancer; Cancer-specific survival; Overall survival; Racial disparity.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Asian Continental Ancestry Group / statistics & numerical data*
  • Endometrial Neoplasms / ethnology*
  • Endometrial Neoplasms / mortality*
  • Endometrial Neoplasms / therapy
  • European Continental Ancestry Group / statistics & numerical data*
  • Female
  • Humans
  • Indians, North American / statistics & numerical data*
  • Kaplan-Meier Estimate
  • Middle Aged
  • Proportional Hazards Models
  • SEER Program
  • Treatment Outcome
  • United States / epidemiology
  • Young Adult