Abstract
A 63-year-old male was seen to have a blackish brown, verrucous surfaced tumor for a duration of almost 8 years on the distal end of his left leg near the medial malleolus. The lesion was 6×4 cm in size and showed slight elevation with an irregular but well-defined border. Histological findings showed slight hyperkeratosis and remarkable acanthosis with many tumor cell nests in the epidermis which were sharply circumscribed from the surrounding epidermis. The tumor cells were uniform and small in size accompanied with intercellular bridges. The cytoplasm contained PAS positive materials but was not stained by alcian blue. Toluidine blue stain (pH 4.1) did not show any metachromasia. There were cystic spaces in the tumor islands, and melanin pigments were observed only in dendritic cells and not in tumor cells.
