Multiple Cutaneous Angiosarcomas after Breast Conserving Surgery and Bilateral Adjuvant Radiotherapy: An Unusual Case and Review of the Literature

Breast angiosarcomas (BAs) are rare but serious events that may arise after radiation exposure. Disease outcome is poor, with high risk of local and distant failure. Recurrences are frequent also after resection with negative margins. The spectrum of vascular proliferations associated with radiotherapy in the setting of breast cancer has expanded, including radiation-associated atypical vascular lesions (AVLs) of the breast skin as a rare, but well-recognized, entity. Although pursuing a benign behavior, AVLs have been regarded as possible precursors of postradiation BAs. We report an unusual case of a 71-year-old woman affected by well-differentiated bilateral cutaneous BA, diagnosed 1.9 years after adjuvant RT for synchronous bilateral breast cancer. Whole-life clinical followup is of crucial importance in breast cancer patients. 1. Introduction Angiosarcomas (ASs) are rare malignant tumors that arise from endothelial cells lining vascular channels [1, 2]. They account for less than 1% of all soft tissue sarcomas and occur in all organs of the body. Approximately 8% of ASs arise in the breast [3]. Primary breast angiosarcomas (BAs) most commonly affect women aged 20 to 40 years without a recognized associated factor [4]. Secondary BAs are usually found in older women at the site of radiotherapy (RT) for breast cancer (BC). They typically involve the dermis and present with skin changes that can easily be misinterpreted even with benign conditions such infection [5]. Neoplastic events attributed to RT in the context of BC are rare. Such occurrences are largely restricted to possible secondary lung and BC, osteosarcomas, malignant fibrous histiocytomas, and fibrosarcomas [5–8]. Postradiation BAs are defined by three characteristics: location in the field of radiation, latency of years after RT, and histologic distinction from the primary neoplasm [9]. The latency period, or interval between RT and the diagnosis of BA, ranges from 3 to 12 years, with most tumors occurring within 6 years after RT [10]. In recent years, the spectrum of vascular proliferations associated with RT in the setting of BC has expanded, including radiation-associated atypical vascular lesions (AVLs) of the breast skin as a rare, but well-recognized, entity [9, 11]. Since clinic and histologic overlap with well-differentiated BA is likely, AVLs represent a diagnostic and therapeutic challenge. Moreover, although pursuing a benign behavior, AVLs have been regarded as possible precursors of postradiation BAs [12]. We report an unusual case of a 71-year-old woman affected by