e14080 Background: A growing number of women newly diagnosed with breast cancer have survived a previous cancer. Although little is known about their prognosis, this population is frequently excluded from clinical trials. Among women diagnosed with incident breast cancer, we examined the impact of previous cancer on overall and cancer-specific survival. Methods: This population-based cohort study included patients age ≥66 years and diagnosed with breast cancer between 2005-2015 in linked SEER-Medicare data. Separately by breast cancer stage, we estimated overall survival using Cox regression and cause-specific survival using competing risk regression for women with and without previous cancer, adjusting for numerous covariates and competing risk of death from previous cancer, other causes, or the incident breast cancer. Results: Of 138,576 women diagnosed with incident breast cancer, 10,822 (7.8%) had a previous cancer of another organ site and many of these (n = 5,014, 46.3%) were diagnosed ≤5 years of breast cancer. For all breast cancer stages except IV in which there was no significant survival difference, women with vs. without previous cancer had worse overall survival (see Table). This survival disadvantage was driven by deaths due to the previous cancer and other causes. In contrast, while women with previous cancer generally had favorable breast-cancer specific survival, the impact of previous cancer on this outcome varied over time. Conclusions: Many women newly diagnosed with breast cancer are already cancer survivors. These women have generally worse overall survival, worse survival from other causes, but their disease-specific survival varies depending on their breast cancer stage and over time. Future analyses will explore time-varying effect of previous cancer on breast cancer survival. [Table: see text]
PMU40 NEWLY DIAGNOSED DEPRESSION AND DEPRESSION SEVERITY AMONG WOMEN WITH INCIDENT BREAST CANCER
