Tumors with Hair Follicle Differentiation

Trichoepithelioma is an autosomal dominant condition characterized by multiple, small, skin-colored papules on the central face, trunk, or proximal extremities (28-31). The cheeks, nose, and nasolabial folds are favorite sites (Fig. 10). Lesions have surface telangiectasias and pearly border and resemble small basal cell carcinomas clinically. Histopathological examination shows islands of small basophilic cells with central keratin cyst formation. Abortive hair germs may be present and peripheral palisading is variable.

Trichofolliculoma (32) presents as a skin-colored, dome-shaped papule on the face and neck. A characteristic feature in some lesions is a central pore containing delicate hairs. On histological examination there is a cystic cavity lined by keratinizing squamous epithelium from which multiple primordial hair follicles arise.

Trichilemmoma presents as a small, warty, flesh-colored papule on the face of an elderly patient. The lesion is solitary and the most frequent location is the nose. When multiple lesions occur, the diagnosis of Cowden's disease is likely, and a search £

for breast cancer is indicated. This disorder is inherited as an autosomal dominant trait. On histopathological examination there are small uniform cells with round or vesicular nuclei that show peripheral palisading.

Pilomatrixoma (calcifying epithelioma) is common in children of both genders. It predominates on the head and neck areas, where more than 70% of the lesions o occur. The lesions tend to be round to oval, dome-shaped, or multilobulated. Size ranges from 0.5 to 5 cm in diameter. Color is usually erythematous, skin-colored, @

Figure 10 Multiple trichoepitheliomas appearing as innumerable skin-colored papules on the face of a young woman. The area to be biopsied was marked with ink.

or yellowish. Individual lesions are firm in consistency and many calcify. On histological examination the tumor is in the lower dermis where a characteristic dual population of basophilic and so-called shadow cells is observed.

How To Reduce Acne Scarring

How To Reduce Acne Scarring

Acne is a name that is famous in its own right, but for all of the wrong reasons. Most teenagers know, and dread, the very word, as it so prevalently wrecks havoc on their faces throughout their adolescent years.

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