A Rare Case of Epithelioid Malignant Peripheral Nerve Sheath Tumor Mimicking Malignant Melanoma.

Malignant peripheral nerve sheath tumors are rare soft tissue sarcomas that are often associated with neurofibromatosis type-1. These tumors share common immunohistochemistry findings which can make diagnosis difficult. We present the case of a woman who presented with a diagnosis of metastatic melanoma of the index finger of her left hand but was eventually diagnosed with primary epithelioid malignant peripheral nerve sheath tumor. We will be highlighting the diagnostic challenge of differentiating between these two very different malignancies.