Primary breast angiosarcoma: A case report.

Rationale: Primary breast angiosarcoma is a rare tumor, accounting for only 0.05% of all malignant breast tumors. The primary breast angiosarcoma typically presents with nonspecific clinical manifestations, which can easily lead to misdiagnosis. Potential factors contributing to misdiagnosis include skin changes that may be erroneously attributed to breast trauma-induced bruising and breast swelling that may be mistaken for inflammatory diseases or other benign tumors.

Patient Concerns: A 19-year-old female was admitted to the hospital due to repeated lump formation in the left breast for 9 months after left breast trauma.

Diagnoses: The diagnosis of primary breast angiosarcoma was confirmed on hematoma biopsy.

Interventions: Due to the patient's condition, no special treatment was given postoperatively. After then, there was a recurrence in the chest wall, and the patient received 2 cycles of chemotherapy, resulting in a reduction in the size and lightening of the recurrent chest wall mass. When chemotherapy intolerance happened, the patient chose to discontinue treatment.

Outcomes: After an 18-month follow-up, the recurrent chest wall mass increased and the patient died from bleeding.

Lessons: Primary breast angiosarcoma has a low incidence but high malignancy, with a high recurrence and metastasis rate, leading to a poor prognosis. The adjuvant chemotherapy, radiotherapy, targeted therapy, and other treatments should be considered to reduce the local recurrence rate and prolong patient survival.