Chondroid lipoma: an update and review.

Chondroid lipoma is a rare, benign soft tissue tumor with features of both embryonal fat and embryonal cartilage that most often arises in the proximal limb and limb girdles of adult women. Histologically, it comprises nests and cords of rounded cells with granular eosinophilic or multivacuolated, lipid-containing cytoplasm within prominent myxohyaline stroma and may be morphologically confused with some sarcomas. Correct diagnosis is crucial to avoid overtreatment because it does not recur or metastasize, and simple excision is curative. The etiology of chondroid lipoma remains unknown, but it appears genetically distinct, with a reciprocal t(11;16)(q13;p13) translocation identified in an increasing number of cases. We review the literature on chondroid lipoma, discussing tumor histology, immunohistochemistry, ultrastructure, and differential diagnosis, and summarize the molecular genetic features so far known.