In 1962, Degos et al1 described an uncommon benign skin tumor, histologically identifiable by sharply demarcated, regular acanthosis. They named it clear cell acanthoma. Under microscopic examination, the tumor was found to consist of pale epidermal cells containing abundant amounts of glycogen, as evidenced by PAS-positive and diastase labile stains. Further clinical and histologic characterization followed publication of this report.2,3
The acanthoma arises as an asymptomatic, single, erythematous papule or plaque, measuring 5 to 10 mm in diameter. It occurs in both sexes, usually in midlife. It most commonly appears on the lower part of the leg, especially on the calf. A fine, scaly layer may cover the tumor, which blanches on diascopy and bleeds easily with minor trauma, mimicking a pyogenic granuloma.
The solitary clear cell acanthoma is an uncommon tumor. Multiple lesions, however, are truly rare, with only 12 cases reported to date. We report herein