OBJECTIVES

Due to lack of reliable and generalizable datasets, knowledge about the real-world treatment of metastatic breast cancer (mBC) patients is still limited. The objective of this study was to assess progression-free survival (PFS) and overall survival (OS) of mBC patients since start of a first-line (1L) systemic treatment in German clinical practice.

METHODS

We analyzed patients included in a new electronic medical record databank targeting German oncology patients (INGRESS-Indivumed Liquid Biopsy RWE oncology database). All mBC patients who received a 1L treatment were included. PFS and OS were assessed using Kaplan-Meier estimations. PFS was defined as time between start of 1L treatment until death or switch to another systemic therapy (whatever came first).

RESULTS

We observed 360 1L-mBC patients (mean age 72.10 years, 98.33% female). In 354 (98.3%) of the patients, a immunohistochemical test for HER2+ was done, 51.4% were HER2+. 272 patients (75.6%) received a 2L treatment and 199 patients (55.3%) a 3L treatment (HER2+: 51.1%, 46.2%). Most often observed 1L treatment was paclitaxel in non-HER2+ and herceptin in patients with HER2+ BC.

Median PFS since start of 1L treatment was 574 days (95%-CI: 373-874; mean: 590 days). In analysed subgroups it was: 371 days for non-HER2+ and 783 days for HER2+.

For OS since start of 1L treatment the median was not reached. Mean OS was 786 days (95%-CI: 735-836) in the overall sample, 719 days (95%-CI: 642-796) in patients with nonHER2+ and 825 days (95%-CI: 764-886) in patients with for HER2+.

CONCLUSIONS

The Indivumed Liquid Biopsy RWE oncology database provides valuable data on immunochemistry/mutation test results and PFS/OS in German clinical practice. Still, PFS and OS are limited in mBC patients.