Myxoid liposarcoma: a case report of a sentinel metastasis to the parotid gland with molecular confirmation.

Myxoid liposarcoma is a subtype of liposarcoma with a predilection for the deep soft tissues of the extremities that accounts approximately for 10% of all adult soft tissue sarcomas. We report a case of a metastatic myxoid liposarcoma to the parotid gland, with fine-needle aspiration cytology correlation and molecular characterization. The lesion was diagnosed in a 53-year-old Hispanic male who presented with a left posterior thigh mass. A core needle biopsy established the diagnosis of myxoid liposarcoma. The patient underwent limb-sparing, wide local excision of the malignancy and later presented with an initial metastatic lesion to the parotid gland. The diagnosis of metastatic myxoid liposarcoma was rendered by fine-needle aspiration cytology with cell block preparation, and molecular confirmation. Although myxoid/round cell liposarcomas are classically described as having minimal pleomorphism on cytologic material, we encountered significant pleomorphism in our case. Therefore, a diagnosis of myxoid/round cell liposarcoma should still be a diagnostic consideration even if markedly pleomorphic cells are seen in fine-needle aspiration biopsies.