Retrospective Observational Study to Determine the Epidemiology and Treatment Patterns of Patients with Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) poses a serious therapeutic challenge due to the occurrence of frequently aggressive, heterogenic, and metastatic tumours. The absence of therapeutic targets for traditional therapies is a hindrance to establishing a standardised therapy for TNBC. There is limited TNBCs epidemiological and real-world data about TNBC treatment regimens in Poland. We retrospectively analysed clinical data from our hospital registry from 2015 and 2020. A total of 8103 individuals with breast cancer were admitted to the MSCI, while 856 (10.6%) were diagnosed with TNBC. Most of the early-stage or locally advanced TNBC individuals had underlying conditions, presented mostly poorly differentiated (G3) stage II tumours and featured a bi-modal age distribution. On average, one-third of all tested TNBCs carried mutations and its identification impacted surgery preference. We observed a significant increase in the use of systemic therapy among TNBCs, whereas carboplatin and dose-dense regimens showed the most prominent upsurge in the neoadjuvant setting. Moreover, the use of neoadjuvants was positively correlated with less invasive breast and lymph node surgeries. The presented data align with general trends observed in other countries and will contribute to expanding knowledge in the planning of treatment regimens and their outcomes.