Silicone breast implant associated fibromatosis

Extra-abdominal desmoid tumors, also known as aggressive or deep fibromatosis, are uncommon soft tissue tumors that rarely involve the breast. Although the exact etiology is unknown, the development of these tumors has been correlated with sites of previous trauma, surgery or in association with familial adenomatous polyposis. Clinically, breast fibromatosis is often mistaken for carcinoma but lacks metastatic potential. It is locally aggressive with high rates of recurrence. The treatment is primarily wide local excision with negative margins. Adjuvant treatments have been suggested and include radiotherapy, chemotherapy and hormonal therapy, however, there are no evidence-based treatment protocols to support their use. Here, we describe a case of fibromatosis that developed within the capsule around a silicone breast implant treated with surgical excision alone. The patient remains recurrence free at 3 months post-operative magnetic resonance imaging.