Fine needle aspiration cytology of pilomatrixoma of the breast

Pilomatrixoma mimicking a breast neoplasm: imaging finding in an uncommon case report

Pilomatrixoma is a rare benign skin tumor originating from piliferous follicles, corresponding to a firm subcutaneous nodule requiring histology for diagnosis. Breast localization is considered to be very rare . Only few breast pilomatricomas have been reported, with imaging showing well defined nodules with microcalcifications, presenting as ACR BI-RADS 4 and 5, suspicious for a breast neoplasm . We report a case of pilomatrixoma of the left breast of a 33 year old woman, appearing as a firm, deep nodule in the lower outer quadrant.The lesion had mammographic and sonographic finding mimiking a breast cancer. Percutaneous biopsy was performed to confirm the histological diagnosis.

Pilomatricoma of the breast in an adolescent girl: sonographic findings

I report a case of pilomatricoma of the breast in an adolescent girl. Sonograms showed a solitary circumscribed, oval, heterogeneously hyperechoic mass in the skin. This is the first description of sonographic findings for this rare tumor in an adolescent breast.

Pilomatrixoma: clinicopathologic study of 51 cases with emphasis on cytologic features

The clinical and pathologic features of 51 cases of pilomatrixoma found in our archives from 1990-1999 were reviewed, with emphasis on the cytopathologic features of the 22 cases that were sampled by fine-needle aspiration (FNA) biopsy prior to excision. Although uncommon, almost 20% of the pilomatrixomas in this series occurred in adults over age 30. Of the commonly reported features, the presence of basaloid cells and ghost cells in FNA smears, associated with a cutaneous location of the lesion, was sufficient for a confident cytologic diagnosis of pilomatrixoma. The presence of foreign body-type giant cells, nucleated squamous cells, and calcification, alone or in combination, was less specific, but supported a diagnosis of pilomatrixoma. Although infrequently reported, prominent nucleoli in basaloid cells and smears containing refractile keratin clumps were very useful clues in the diagnosis of pilomatrixoma. Finally, the routine use of cell blocks is recommended because in many of the cases presented ghost cells were fragmented or obscured in smears, but were more readily identified in cell block sections.