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[Radiation-induced angiosarcoma of the breast].

Background Radiation-induced angiosarcomas of the breast are rare secondary malignancies that occur after adjuvant radiation of breast cancer. They grow in a multifocal manner and frequently develop local recurrences. Therefore, they often pose a surgical challenge. Due to their rarity it is still unclear whether a radical surgical approach leads to a beneficial outcome. The aim of this study was to determine the prognostic significance of surgical margins. Patients and methods We retrospectively assessed the outcome of 18 patients who underwent surgical treatment at our institution. The median follow-up was 4.4 years. Univariate analyses were performed to determine the prognostic significance of the assessed factors on local recurrence-free survival (LRFS) and overall survival (OS). Results The median patient age was 66.3 years. The median latency between radiation and angiosarcoma occurrence was 6.9 years. The estimated 5-year rates for LRFS and OS were 25.0% (95% confidence interval [CI]: 7.8-47.2) and 53.8% (95% CI: 26.8-74.8). R0 resection of the primary lesion was associated with a significant improvement in LRFS (p=0.017) and OS (p=0.013). Moreover, R0 resection of the last local recurrence was also associated with a more favourable OS (p=0.040). Conclusions Due to their aggressive growth pattern and pronounced tendency to local recurrence, a radical surgical approach should be sought in the treatment of radiation-induced angiosarcomas. Wherever feasible, surgical treatment should aim at R0 margins in order to improve local control and OS.