599 Intramammary Melanoma Micrometastasis Within A Silicone Implanted Breast
Abstract Case Summary Melanoma of the abdominal wall is not uncommon, and sentinel lymph nodes are usually located in the lymphatic drainage basins of the axilla or inguinal region. Less frequently, interval sentinel lymph nodes can be found along the lymphatic vessels between the primary cancer and nearest basin. We present the case of a 53-year-old female with silicone breast implants who underwent scar excision and sentinel lymph node biopsy for a 1mm Breslow thickness superficial spreading melanoma of the abdomen. Two lymph nodes were excised; both lying in the subcutaneous fat at the lateral aspect of the right breast capsule. Lymph node histology revealed a subcapsular melanoma deposit along with silicone lymphadenopathy in the sentinel node, and silicone lymphadenopathy in the second node. Whole body positron emission tomography (PET/CT) and magnetic resonance imaging (MRI) of the brain showed no evidence of metastases or implant rupture. Subsequent MRI breast revealed likely intracapsular implant rupture. The patient was offered removal of implants and remains under follow-up. The unusual location of the sentinel node in our patient highlights the possibility that previous breast augmentation may have altered the pattern of lymphatic drainage to the axilla. In addition, to our knowledge, this is the first reported case of silicone and melanoma deposits in a single sentinel node.