ABSTRACT
Combined nevi consisting of a Spitz nevus and an acquired nevus are unusual, and, to our knowledge, the combination of a spindle cell Spitz nevus and an overlying compound nevus has not been previously reported. We report a 17-year-old girl with a nodule on the left anterior lower extremity. The nodule was asymptomatic, firm, brown, symmetrical, dome-shaped, 8 mm in diameter, and not found with ulceration. Histological findings showed proliferation of spindle-shaped cells with an overlying compound nevus. The spindle-shaped cells were large, non-pigmented, uniform in size and shape, with rare mitoses and without nuclear atypia, and arranged in a storiform pattern in thick collagen bundles. They stained positively for S-100 and negatively for HMB-45. The lesion was considered to be a new type of combined nevus consisting of a spindle cell Spitz nevus and an overlying compound nevus.
Subject(s)
Nevus, Epithelioid and Spindle Cell/pathology , Nevus, Intradermal/pathology , Nevus/pathology , Skin Neoplasms/pathology , Adolescent , Female , Humans , Immunohistochemistry , Leg , Melanocytes/pathologyABSTRACT
Case 1 was a 20-year-old male with a nodule on the scrotum. Case 2 was a 14-year-old female with a dome-shaped, reddish-brown nodule on the nose. Case 3 was a 30-year-old male with a dome-shaped, reddish-brown nodule on the forearm. All of the excised specimens showed typical features of solitary reticulohistiocytic granuloma. There were histiocytes and multi-nucleated giant cells in the dermal tumorous nests. They were stained positively with PAS reaction and anti-lysozyme antibody, but were stained negatively with S-100 protein antibody. To clarify the nosology of the reticulohistiocytic granuloma, we reviewed the literatures of multicentric reticulohistiocytosis and adult xanthogranuloma. Multicentric reticulohistiocytosis was considered to be a systemic disease and different from solitary reticulohistiocytic granuloma. However, adult xanthogranuloma showed clinical similarities to solitary reticulohistiocytic granuloma instead of the differences in the histopathologic features.
