Trichoepithelioma

A benign skin tumor derived from hair follicles

Trichoepithelioma is a benign skin tumor that originates from the hair follicle. It is characterized by the presence of small, flesh-colored papules, primarily occurring on the face. Trichoepitheliomas are generally considered to be harmless, but they can be of cosmetic concern to patients.

Pathophysiology

Trichoepitheliomas arise from the pilosebaceous unit, which includes the hair follicle, sebaceous gland, and arrector pili muscle. These tumors are thought to result from a genetic mutation that affects the normal development of hair follicles, leading to the formation of tumor-like growths.

Clinical Presentation

Trichoepitheliomas typically present as small, firm, flesh-colored papules. They are most commonly found on the face, particularly around the nose, cheeks, and forehead. The lesions are usually asymptomatic, but they can sometimes be itchy or tender.

Histological image of trichoepithelioma showing basaloid cells and keratin cysts.

Histopathology

Under the microscope, trichoepitheliomas are characterized by nests of basaloid cells with peripheral palisading. These nests are often surrounded by a fibrous stroma and may contain keratin cysts. The histological appearance can sometimes resemble that of basal cell carcinoma, making accurate diagnosis important.

Diagnosis

The diagnosis of trichoepithelioma is primarily clinical, supported by histopathological examination. A skin biopsy is often performed to confirm the diagnosis and to differentiate it from other similar conditions, such as basal cell carcinoma or syringoma.

Treatment

Treatment is not always necessary for trichoepitheliomas, as they are benign and typically asymptomatic. However, for cosmetic reasons or if the lesions are symptomatic, options include:

• Surgical excision
• Laser therapy
• Cryotherapy
• Electrodessication and curettage

Prognosis

The prognosis for individuals with trichoepithelioma is excellent, as these tumors are benign and do not metastasize. However, they may recur after treatment, and multiple lesions can develop over time.

Related pages

• Basal cell carcinoma
• Pilomatricoma
• Sebaceous gland
• Skin tumor

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