Home > E. Pathology by systems > Skin > trichilemmoma

trichilemmoma

Thursday 3 January 2013

tricholemmoma

Definition: Trichilemmoma is a cutaneous benign adnexal tumors that differentiates toward cells of the outer root sheath. The lesion is often seen in the face and neck region.

They are a benign lesion derived from hair follicles. The lesions are symmetrical and show increasing clear cytoplasm moving deeper into the dermis due to glycogenation. Papillomatosis, hyperkeratosis, and peripheral palisading are also common.

Cowden syndrome

Multifocal occurrence is associated with Cowden syndrome , patients with which exhibit hamartomatous intestinal polyposis as well as tricholemmoma.

Cowden syndrome (multiple hamartoma syndrome) is characterized by multiple hamartomas, soft tissue tumors, skin tumors, breast cancer, and GI polyps. It is caused by PTEN mutations.

Trichilemmomas, especially when multiple, are associated with Cowden syndrome.

Synopsis

outer root sheath differentiation

Images

trichilemmoma