LAUSR

Melanoma can rarely show malignant chondro‐osseous differentiation and can cause diagnostic confusion. We report 3 cases of primary melanoma with extensive bone and cartilage matrix. The first case arose in the nasal mucosa of a 72‐year‐old woman, the second case in the left index finger of a 26‐year‐old woman and the third case in the left cheek of a 68‐year‐old woman. In tumors where osseous and chondroid differentiation appear in mucosa and skin, primary melanoma with chondro‐osteosarcomatous differentiation should be considered in the differential. Careful histological examination together with clinical correlation and ancillary immunohistochemical studies can ensure the correct diagnosis is made.