SCALLOPED CELL XANTHOGRANULOMA

Aims: We describe nine cases of scalloped cell xanthogranuloma, a dist inct solitary variant of non-langerhans cell histiocytoses, Methods an d results: In this retrospective clinicopathological study scalloped c ell xanthogranuloma mostly occurred on the back or head and neck of yo ung adult males diagnosed as a xanthogranuloma, naevus, or basal cell carcinoma, Histology characteristically revealed a sheet-like infiltra te of predominantly scalloped histiocytes (> 75% of all cell types) in the upper dermis, Other mononuclear (vacuolated, xanthomatized, spind le-shaped, oncocytic) and multinucleate (foreign body ground glass and Touton) histiocytes were also regularly seen, Immunohistochemically, all cases exhibited a macrophage/dendritic cell lineage positive with KP1 (CD68), KiM1p, HAM 56 and factor XIIIa. Ultrastructurally, numerou s intracytoplasmic dense, occasionally also myeloid bodies were presen t. No associated systemic disease, hyperlipidaemia or recurrence were seen during follow-up. Conclusions: These findings are similar to thos e of early lesions of xanthoma disseminatum; thus, scalloped cell xant hogranuloma could be regarded as a solitary counterpart of xanthoma di sseminatum, and, moreover, fits neatly into a unifying concept of non- Langerhans cell histiocytoses.