Long-Term Trends in the Survival of Women with Endometrial Cancer in Canada: A Population-Based Study

Laurie Elit, Alice Lytwyn, Noori Akhtar-Danesh

Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Canada.

DOI: 10.4236/jct.2012.325109                

Abstract

Introduction: Annually in Canada, endometrial cancer affects approximately 4500 women and 790 are expected to die of their disease. To better understand survival trends across the country we undertook this population based study of Canadian women diagnosed with endometrial cancer. Long term trends in relative survival were evaluated by age and geographic region of residence. Methods: Women with an ICD-10 code of C54 and endometrial cancer were identified from the Canadian Cancer Registry. They were included if the incident diagnosis occurred between 1992 and 2005, and they were 16 years and older at diagnosis. A flexible parametric model was used to determine relative survival ratio (i.e., the observed survival rate among cancer patients divided by the expected survival rate in the general population). Results: 18,486 women were diagnosed with endometrial cancer. Mean age was 63.4 (SD=11.8) year. Relative survival decreased with each successive age group cohort of patient (16-49 yr compared to over 60 years, p<0.001). When relative survival was adjusted for age, women in British Columbia had the best outcomes (eastern Canada compared to other jurisdictions p<0.001). Five-year survival outcomes improved for each age group cohort during the 1992 to 2005 time frame. Conclusions: Regional variations in relative survival were identified across Canada for women with endometrial cancer. This suggests that other factors related to the patient or processes of care are involved. Examining these factors in further detail may provide opportunities to improve the care of women with endometrial cancer in Canada.

Keywords

Endometrial Cancer; Relative Survival

Conflicts of Interest

The authors declare no conflicts of interest.

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