Abstracts by keywords: endocrine therapy
Breast cancer (BC) is the most common cancer among women in Germany, with around 69,000 new cases every year; 18,591 women died of BK in 2015 (Barnes et al., 2016). Approximately 70% of all newly diagnosed women with BK have a hormone receptor-positive tumor (HR+) who are eligible for primary adjuvant endocrine therapy (ET) with either tamoxifen (TAM) or an aromatase inhibitor (AI) (Franzoi et al., 2021) . Depending on the menopausal status, this standard therapy is taken daily for at least 5 years, significantly reduces the risk of BK recurrence and improves the overall survival of the patients (Waks & Winer, 2019, Font et al., 2022). Despite the proven effectiveness in preventing BK recurrence by 40%, approximately 50% of women take less than 80% of the prescribed dose. In addition, up to 50% of patients with BK discontinue their ET (Hadji et al., 2013; Moon et al., 2019; Peddie et al., 2021). It should be noted that both TAM and AI therapy can cause short- and long-term side effects in patients. These include hot flashes, myalgias and osteoporosis (Franzoi et al., 2021; Group et al., 2009). The occurrence of TAM- and AI-related side effects may therefore negatively impact a patient's persistence to ET. Persistence is defined as the continuation of drug use for the prescribed length of time (from initiation to discontinuation) while a patient adheres to the prescribed interval and dose of a dosing regimen (Cramer et al., 2008; Hadji et al., 2013). Recently, adherence to therapy and the persistence of ET in women with HR+ BK have been the subject of intense debate in the literature, since "non-adherence" to ET has been shown to be associated with an increased risk of disease recurrence (Font et al., 2019; Seneviratne et al ., 2015), for distant metastases (Blanchette et al., 2020; Lee et al., 2019) and for mortality (Inotai et al., 2021; Lao et al., 2019; Murphy et al., 2015). However, no study has yet investigated whether there is a connection between the health insurance company a woman has and her persistence in ET. The aim of this study was therefore to analyze persistence with TAM and AI and to show possible differences specific to health insurance companies.