Two cases of eccrine angiomatous hamartoma

Eccrine angiomatous hamartoma is a rare benign tumor similar to hemangioma in appearance. Unlike hemangioma, it has numerous eccrine structures in addition to numerous capillary channels. Occasionally it accompanies hyperhidrosis and pain. The sweat apparatuses in the lesions showed antigenic activities by immunohistochemical stains, particularly with anti-S100 protein and anti-CEA, the two common antigens associated with eccrine sweat glands. The antigenic activities of anti-S100 protein and anti-CEA in sweat gland structure of 2 presenting cases, one with sweating and the other without sweating, were compared to each other. As a result, we found no differences between the two cases. Although an aggressive treatment is not required due to its benign nature, total excision can be considered in cases with severe symptoms. We present two cases of eccrine angiomatous hamartoma developed on right knee joint areas in a 2-year-old male and a 10 month-old male, respectively.