(2022) 22:130 Heinig et al BMC Cancer https://doi.org/10.1186/s12885-022-09240-w Open Access RESEARCH Initial and ten‑year treatment patterns among 11,000 breast cancer patients undergoing breast surgery—an analysis of German claims data Miriam Heinig1*, Franziska Heinze2, Sarina Schwarz1 and Ulrike Haug1,3 Abstract Background: We aimed to explore the potential of German claims data for describing initial and long-term treatment patterns of breast cancer patients undergoing surgery Methods: Using the German Pharmacoepidemiological Research Database (GePaRD, ~ 20% of the German population) we included patients with invasive breast cancer diagnosed in 2008 undergoing breast surgery and followed them until 2017 We described initial and long-term treatment patterns and deaths Analyses were stratified by stage (as far as available in claims data), age at diagnosis, and mode of detection (screen-detected vs interval vs unscreened cases) Results: The cohort comprised 10,802 patients The proportion with neoadjuvant therapy was highest in patients