Abstract
A 27-year-old man developed calcifying epithelioma with bulla-like appearance on his left upper arm. He noticed a small mass 4 months before his first visit. It had been enlarging rapidly and took about 2 months to show a bulla-like appearance. Clinically, it was a dome-shaped soft tumor, measuring 20 mm in diameter, was purplish-reddish in color and translucent. A hard nodule was palpable inside. An ultrasonic examination showed an irregularly distributed echo-pattern with echolucent border and acoustic shadow. The histological examination revealed that many enlarged cavities had formed in the upper dermis above a typical tumor mass of calcifying epithelioma. We suspected that the walls of the cavities were lymphatic, because they were stained with neither anti-factor VIII related antigen nor UEA-I. Another findings that the melanin granules were decreased in the granular layer of the epidermis above the tumor mass, have not been previously reported. The clinical and histological features of calcifying epithelioma with a bulla-like appearance thus far reported in Japan (108 tumors of 100 patients) including our case were also analyzed.
