The landscape of palliative systemic therapy and overall survival analysis of elderly patients with advanced breast cancer in China National Cancer Center

Objective To compare the survival data of elderly advanced breast cancer (ABC) patients in China National Cancer Center with USA and summarize the therapeutic characteristics in elderly ABC patients via real world study. Methods We summarized the clinicopathological characteristics, therapeutic regimens and survival outcome of 1 425 females with ABC who were initially hospitalized between January 2003 and December 2013 from Database in China National Cancer Center and compared with 21 185 ABC patients in the Surveillance, Epidemiology, and End Results (SEER) database. Results The median overall survival (OS) of elderly patients was significantly shorter than that of the young group in China National Cancer Center (35.5 months vs. 43.9 months; χ2=8.747, P=0.003), which was similar to the survival feature in SEER database (24.0 months vs. 36.0 months; χ2=540.227, P<0.001). Compared with the young population, significantly more elderly patients suffered from the medical complications of hypertension [30.3% (67/221) vs. 9.5% (114/1 204); χ2=73.073, P<0.001], diabetes [14.5% (32/221) vs. 4.7% (57/1 204); χ2=30.220, P<0.001] and heart disease [6.3% (14/221) vs. 1.7% (20/1 204); χ2=17.638, P<0.001]. In estrogen receptor (ER) and/or progesterone receptor (PR)-positive patients, the percentage of receiving first-line endocrine therapy in elderly patients was significantly larger than that of the young population [26.9% (43/160) vs. 9.5% (80/841); χ2=37.599, P<0.001]. Moreover, in ER and/or PR-positive population, the elderly patients underwent first-line endocrine therapy resulted in better OS than those underwent first-line chemotherapy (49.9 months vs. 32.6 months; χ2=4.774, P=0.029), while no significant difference was observed between these two therapeutic modes in the young population (56.9 months vs. 48.8 months; χ2=1.103, P=0.294). Conclusion The proportion of elderly ABC patients with the medical complication of hypertension, diabetes and heart disease is significantly larger than that of the young population, which may lead to the difference in treatment decision making. In ER and/or PR-positive elderly ABC patients, receiving first-line endocrine therapy may result in better survival than first-line chemotherapy. Key words: Breast neoplasms; Aged; Therapy; Drug therapy