Dermal Analog Tumor
In contrast to classic basal cell adenomas, dermal analogue tumors are frequently multilobular and unencapsulated. The histologic appearance is characterized by the presence of cell islands surrounded by thick eosinophilic membranes resembling a jigsaw puzzle. The hyaline membrane material represents a reduplicated basal lamina which is diastase resistant and PAS-positive. Mitosis and perineural invasion is usually absent.