8110/3 Pilomatrix carcinoma


Pilomatrixoma, malignant
Pilomatricoma, malignant
Matrical carcinoma


ICD-O-3 topography code: C44
ICD10: C44

Pilomatrix carcinoma is a very rare, locally aggressive, malignant neoplasm of the hair follicle. The majority of cases arise de novo, however malignant transformation from a pre-existing pilomatrixoma has been reported. The tumour usually presents as a large (1-10cm), asymmetrical, solitary nodule in the head and neck, upper extremities, or buttocks. Morphologically, it is characterized by the presence of aggregates of basaloid cells infiltrating the dermis. Masses of ghost cells are present in the cellular aggregates. Foci of necrosis, calcification and ossification are common observations.
Pilomatrix carcinoma affects predominantly adult patients, the mean age at diagnosis is 48 years. There is a predilection for males (ratio 2:1). Complete surgical excision is the treatment of choice. If the tumour is not completely removed, it usually recurs, but it rarely metastasizes to distant anatomic sites1
LeBoit PE, Burg G, Weedon D, Sarasin A (Eds.)
World Health Organization Classification of Tumours. Pathology and Genetics of Skin Tumours
3rd Edition
IARC Press: Lyon 2005