Eosinophilic globules in Spitz's nevi. New findings and a diagnostic sign.

Dull pink globules were found within the epidermis in 65% of junctional, 75% of compound, and 25% of intradermal types of Spitz's nevi (the nevi of large spindle and/or epithelioid cells). These globules were PAS-positive, diastase-resistant and also were positive with the trichrome stain. Similar-appearing eosinophilic globules were noted in the epidermis in only 2% of malignant melanomas and in but 0.9% of ordinary melanocytic nevi. The globules in malignant melanomas and in ordinary melanocytic nevi were negative with PAS and trichrome stains. Therefore, the finding of PAS- and trichrome-positive eosinophilic globules within the epidermis is a helpful sign for histologic differentiation of Spitz's nevus from malignant melanoma.