Leiomyosarcomas are the least frequent primary breast sarcomas, making it an extraordinarily rare malignancy. The clinical manifestation of this entity as a fungating breast wound is, on its own, highly unusual in developed nations, mainly due to the improvement of worldwide screening programs and easier access to health care. Management of this breast wound remains challenging, and an accurate histopathological diagnosis is essential for a proper treatment plan. Thus, we present this rare case of metastatic breast leiomyosarcoma to contribute to the scarce literature regarding this disease.