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.