A Rare Case of Angiomyxolipoma: Differential Diagnosis From Other Vascular and Myxoid Tumors

A case of angiomyxolipoma in the posterior neck region of a 36-year-old man is presented. Although lipomatous tumors are very frequent among benign soft tissue neoplasms, angiomyxolipoma has been reported only in seven case studies before. We present a new case of a typical angomyxolipoma. Histopathologically, admixture of mature adipocytes, poorly cellular myxoid spindle cell areas and abundant vascular structures are the striking components of this tumor. Myxoid spindle cell lipoma, vascular spindle cell lipoma, myxoid liposarcoma, myxolipoma, angiolipoma and pseudoangiomatous spindle cell lipoma can be considered in the differential diagnosis of angiomyxolipoma. Immunohistochemistry is usually helpful in the diagnosis of this extremely rare entity. In our case, positive staining for vimentin and sparse positivity for CD34, in the absence of reactivity for SMA, desmin, S-100 protein and HMB45 in the spindle cells, are the most important immunohistochemical features that help in the differential diagnosis.