A rare variant of pilomatricoma: pseudobullous pilomatricoma.

Pilomatricoma (PM; calcifying epithelioma of Malherbe) is a benign tumor originating from the matrix of the hair follicles. Clinical types of the tumor are familial, perforating, multinodular, exophytic, anetodermic, and giant PM. The bullous type is seen only in 3 to 6% of cases. Because the bullous areas detected in PM are filled with lymphatic liquid, some authors use the term pseudobulla. This report presents a 26-year-old female patient that was diagnosed with pseudobullous PM based on clinical, radiologic, and histopathological findings, and the pathogenesis of the bullous appearance of PM is reviewed from the literature.