Rare presentation of a primary cutaneous well differentiated liposarcoma

A 61-year-old man with a history of malignant melanoma in-situ presented with a 1-year history of a large firm nodule on his back. Physical exam revealed a 3 × 2 cm firm, nontender, mobile nodule on his right back. A punch biopsy was obtained revealing subcuticular adipose tissue with a lobular architecture that contained enlarged, markedly pleomorphic, and hyperchromatic nuclei at the periphery of the fat lobules and was interpreted as a well differentiated liposarcoma. Liposarcomas of the skin are exceedingly rare and represent a diagnosis of exclusion regarding histopathologic mimics, metastases, and direct extensions from deeper tumors.