Abstract P1-07-11: Improved long term survival from breast cancer over three decades: Persistent disparities with age, but not socioeconomic status, in a socialized heath care system
Authors: Malin A , Ashfield AM , Purdie CA , Jordan LB , Thompson AM 
Published: May 2016

Background

Socioeconomic status and patient age have been associated with disparities in survival for breast cancer. We previously reported breast cancer diagnosed in a geographically defined population treated in a single cancer center in a socialized heath care system (free health care) with a 5 year survival of 70% (95% CI 67-74%) (reported in 1998) and, in the same cohort, a10 year survival of 52.7% (95% CI 50.03-55.1%)(reported in 2001). Since that time, multidisciplinary team discussion of every patient at diagnosis, before and after surgery, together with improved drug therapy and radiotherapy techniques have been implemented using national guideline, evidence-based protocols. This study examined survival for the population based cohort of women from the same geographical region treated over 5 years from 2000 to seek evidence of improved outcomes and persistent disparities compared with historical practice.

Methods

Between 2000-2004, a cohort of 1851 women were treated at a single cancer center, representing 98% of the incident breast cancer patients in the geographic region. Prospective electronic clinical data collection was retrospectively manually cross checked with patient records and death certification. While breast screening practice changed little over that time, multidisciplinary team discussion of every patient, second and third generation chemotherapy regimens and hypofractionation of radiotherapy were introduced when compared with pre-2000.

Results

At a median 8.8 years follow-up, amongst 1851 women there were 768 deaths, 342 from breast cancer, and 405 women diagnosed with recurrent disease. The 5 year breast cancer specific survival was 82% and disease free survival 80% (87% and 84% respectively for operable disease) and at 10 years 76% breast cancer specific survival and 75% disease free survival (82% and 78% respectively for operable disease). There were the expected associations between tumor size, grade, node status, estrogen receptor, progesterone receptor, HER2 and disease free or overall survival. Breast cancer specific mortality was significantly better in the &lt;50 years (HR 0.60; 95% CI 0.42-0.85) and 50-69 years (HR 0.69; 95% CI 0.51-0.95) age groups compared with women &gt;70 years. While deprivation was an independent risk factor for all-cause mortality, after adjustment for age, tumor size, grade and node status, breast cancer specific survival was not significantly associated with socioeconomic status.

Conclusions

Over a 30 year period, survival from breast cancer has dramatically improved, likely due to multidisciplinary evidence based practice, including new drugs and enhanced delivery of radiotherapy. While disparities by socioeconomic status have declined, women &gt;70 years age continue to have a worse breast cancer specific survival.

Citation Format: Malin A, Ashfield AM, Purdie CA, Jordan LB, Thompson AM. Improved long term survival from breast cancer over three decades: Persistent disparities with age, but not socioeconomic status, in a socialized heath care system. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-07-11.