Abstract: To investigate the clinical and histopathological features of,hidroacanthoma simplex (HS), the data of 5 patients with HS diagnosed from January 2015 to August 2020 in our hospital and 16 patients with HS in reported studies searched in CNKI were analyzed. Results showed the age at onset ranged from 36 to 86 years with the mean of 61.1 years. Of 21 patients, 13 were female, 8 were male, and the course of the disease ranged from 5 months to 50 years. The lesions mainly located on lower extremities and the trunk. Skin biopsy features were the “Jadassohn phenomenon” composed of bland basaloid cells that were smaller than neighboring epidermal keratinocytes, and intracytoplasmic glycogen and occasional ductal structures within the nests of cells were also found. Immunohistochemical examination showed the cytoplasm of some tumor cellsa positive for EMA and the normal ductal structure positive for CEA. Sixteen patients were received resection with no recurrence and malignant transformation in follow-up, and the treatment is unknown in 5 patients. 

Key words: hidroacanthoma simplex, clinicopathological analysis