Primary Angiosarcoma of the Breast: A 20-Year Single-Institution Experience in China

Background. Primary angiosarcoma of the breast (PAS) is a rare aggressive tumor with no standardized treatment. The aim of this study was to investigate the characteristics of all primary angiosarcoma of the breast obtained from a single center and the features peculiar to Chinese patients. Methods. The medical records at Tianjin Medical University Cancer Institute and Hospital were retrospectively searched to identify all cases of PAS treated in 2000-2019. Results. Sixteen cases of PAS were identified, and most involved the left breast. Forty percent of young patients had a history of progressive tumor enlargement with localized pain and skin color changes. The diagnostic accuracy rate was 66.7% for MRI, 75% for core-needle aspiration, and 58.3% for intraoperative fast frozen pathology. The most common surgery was modified radical mastectomy (n = 9, 56.25%). All positive margins involved the pectoralis major muscle, and these tumors' mean size was 8.2 cm. All cases were CD34 positive, and the Ki-67 index was >= 30% in 37.5%. Median local or distant recurrence-free survival was 57.6 months for low-to-moderate-grade tumors and 23.5 months for high-grade tumors. Seventy-five percent of the patients were treated with chemotherapy. The average tumor size in patients with relapse-free survival longer than 3 years was 2.2 cm. Conclusion. Young patients may have larger and softer breast tumors with skin color changes. MRI and core-needle biopsy should be performed preoperatively. A positive surgical margin at pectoralis major should be noted. Breast prosthesis may be a better reconstruction option. Adjuvant chemotherapy and/or radiotherapy should be considered for large tumors with a high Ki-67 index or high-grade tumors.