Positive response of a primary leiomyosarcoma of the breast following salvage hyperthermia and pazopanib

Primary sarcomas of the breast are rare tumors, accounting for less than 1% of all breast neoplasms. Leiomyosarcoma is an extremely rare subtype of breast sarcoma [1]. Prognoses for primary breast sarcoma are poor and treatment modalities are limited. Pazopanib is an oral, multitargeted tyrosine kinase inhibitor, with activity against vascular endothelial growth factors (VEGFs) 1, 2, and 3, and platelet-derived growth factors (PDGFs) [2]. Pazopanib has been approved for the treatment of advanced renal cell carcinoma and metastatic soft tissue sarcoma (STS) [2]. Hyperthermia inhibits sub-lethal cellular damage repair and improves oxygenation; thus, making it an attractive therapy for combining with radiation and/or chemotherapy to generate a potentially synergistic response. Hyperthermia has a proven benefit for treating STS [3]. Herein, we report a case of primary breast leiomyosarcoma treated with regional hyperthermia and pazopanib.