The lesion was composed of spindle and oval shaped cells with eosinophilic finely granular cytoplasm. A considerable number of cells had foamy cytoplasm. The nuclei were round, oval or reniform and an occasional regular mitosis was seen. The giant cells, mostly of Touton type, were scattered in the lesion (Figs. 02, 03, 04, 05, 06, 07 and 08). Some giant cells showed the phenomenon of emperipolesis. Some scattered B lymphocytes and small clusters of T lymphocytes were also present. Immunohistochemically majority of histiocytes and giant cells were labeled with antibodies against CD68 (Fig 11), MAC387 (Fig. 12), and S-100 protein (Fig. 09) while there was no labeling with anti-CD1a antibodies (Fig. 10). Electron microscopic examination of the lesion did not demonstrate Birbeck granules.
Subsequent examination of the patient did not reveal any similar lesion either in the skin or in other location.
DIAGNOSIS AND DISCUSSION