Metastatic breast cancer: prolongation of survival in routine care is restricted to hormone-receptor- and Her2-positive tumors

18,000 women die due to metastatic breast cancer in Germany per year. Median survival is 20–28 months after diagnosis. The question we wanted to answer was whether survival has improved in routine care? For this purpose we conducted a retrospective analysis of all patients with metastatic breast cancer who were treated between 06/1995-06/2013 in a community-based oncology group practice in Germany. 716 patients were analyzed with a median age of 61 (31–93). Localizations of metastases were distributed as follows: 47% visceral, 36% bone, 9% lymphatic, 4% CNS, 4% others. 79% were hormone-receptor-positive, 20% Her2-positive, 9% triple-negative. Median overall survival was 34 months (95% Confidence Interval: 31–37), median disease-specific survival 36.8 months and disease-specific survival after 5 years 34%. Survival was significantly correlated with localizations of metastases, number of metastasized organs, disease free survival since initial diagnosis, hormone-receptor status and age. Patients with hormone-receptor-positive tumors had a median overall survival of 37 months, Her2-positive patients of 34 months and triple-negative patients of 13 months. 86% of hormone-receptor-positive patients received antihormonal therapy. 81% of Her2-positive patients received anti-Her2 therapy. In summary, longer survival is strongly restricted to hormone receptor- and Her2-positive tumors most likely due to targeted therapies directed against the estrogen-receptor and Her2.