Initial and ten-year treatment patterns among 11,000 breast cancer patients undergoing breast surgery—an analysis of German claims data

Abstract

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 < 50 years (19% vs. ≤ 8% at older ages). The proportion initiating adjuvant chemotherapy within four months after diagnosis decreased with age (< 50 years: 63%, 50–69: 46%, 70–79: 27%, 80 + : 4%). Among women < 69 years, ~ 30% had two breast surgeries in year one (70–79: 21%, 80 + : 14%). Treatment intensity was lower for screen-detected compared to interval or unscreened cases, both in year one (e.g., proportion with mastectomy ~ 50% lower) and within 2–10 years after surgery (proportions with radiotherapy or chemotherapy about one third lower each). Conclusions This study illustrates the potential of routine data to describe breast cancer treatment and provided important insights into differences in initial and long-term treatment by mode of detection and age.

Keywords

• Breast cancer
• Cancer treatment
• Claims data
• Screening