Trichofolliculoma - Causes, Symptoms, and Treatment

Introduction:

Trichofolliculoma is a small, single, and non-cancerous (benign) nodule that arises from the hair follicle. Generally, the condition is reported in people of all ages. However, children and young adults are more commonly affected. The head and neck regions are the affected regions. The causes and risk factors for trichofolliculoma are unknown. Usually, there is no need for treatment unless it causes dangerous symptoms and cosmetic concerns to the affected person. The condition can be managed with surgical excision. The prognosis of the condition is excellent, with proper diagnosis and treatment. The article discusses trichofolliculoma, its causes, risk factors, symptoms, diagnosis, and treatment.

What Is Trichofolliculoma?

Trichofolliculoma is an uncommon, single, and benign condition that starts from the hair follicle tissue. It is characterized by the presence of small flesh-colored and occasionally white-colored nodules on the face and nose region. The condition may affect the eyelid, which is called the cotton bag sign. These nodules are painless and may have a tuft of fine hairs. These regions sometimes contain hair follicles. Sometimes, these nodules have a central pore or black dot. The fluid, such as sebaceous fluid or sebum, comes out through these pores, which is known as the pore of Winer. The other name for trichofolliculoma is folliculoma and trichofolliculoma of hair follicles.

What Are the Causes and Risk Factors of Trichofolliculoma?

Trichofolliculoma can affect an individual at any age. However, people in pubertal, adolescence, and early adulthood are more likely to be affected by the condition. Both males and females are more susceptible to being affected by the condition. People of all ethnic and racial groups can be affected. Furthermore, there is no geographical distribution of trichofolliculoma. The causes and risk factors of trichofolliculoma are unknown. The causes and risk factors for trichofolliculoma are as follows:

• Minor trauma and injuries to the skin may affect the abnormal growth of hair follicles and cause trichofolliculoma.

• Chronic sun exposure can cause skin damage and lead to the development of skin conditions.

• Fair-skinned people and people with a history of non-cancerous skin conditions are at high risk of developing trichofolliculoma.

What Is the Pathophysiology of Trichofolliculoma?

The pathophysiology of trichofolliculoma is described below:

• Development of Abnormal Hair Follicles: The development of abnormal hair follicles occurs due to abnormal differentiation of follicular epithelial cells. The dilated hair follicle is at the center, surrounded by several secondary hair follicles. The central part comprises hair shafts and sebaceous fluid that may exude from it.

• Development of Primary Follicle: A primary infundibular cystic structure forms with a thin wall and radiating secondary follicles.

• Development of Secondary Follicle: The central or primary hair follicles are surrounded by several secondary follicles. The secondary hair follicles contain sebaceous glands and hair shafts.

• Development of Tertiary Follicle: The secondary follicles regress to tertiary follicles. There will be a variation in the size of hair from vellus hair to thick terminal hair.

• Development of Quaternary Follicle: The tertiary follicle regresses to the quaternary follicle.

What Is the Histology of Trichofolliculoma?

The development of primary follicles characterizes Trichofolliculoma. This follicle is in the cystic space, lined by squamous epithelium. Secondary and tertiary follicles surround the primary follicle. The hair follicles are surrounded by well-circumscribed dense stroma. The surrounding hair follicles are tiny in size. These may be intermixed with Merkel cells and sebocytes. With the sebaceous variant, the condition is called sebaceous trichofolliculoma. Trichofolliculoma can be developed into other lesions, such as folliculosebaceous cystic hamartoma.

What Are the Signs and Symptoms of Trichofolliculoma?

The signs and symptoms of trichofolliculoma are as follows:

• Nodules: The presence of single and raised nodules on the skin. In some cases, there may be an appearance of several multiple nodules.

• Size: Trichofolliculoma is a slow-growing solitary tumor, and the average size is 0.2 to 0.5 centimeters with a central depression.

• Tumor Color: There will be reddish discoloration of the skin over the nodules. A tuft of fine hair will be at the center of the nodule.

• Painless: The affected person may not experience any pain or itchiness. The borders of the nodules are demarcated and are firm on touch.

• Location: The nodules can appear all over the body but commonly appear on the neck and head regions.

How Is Trichofolliculoma Diagnosed?

The diagnostic procedure for trichofolliculoma is as follows:

• Medical History: The healthcare provider may ask the patient about a family history of trichofolliculoma and may ask about any previous history of the presence of nodules.

• Physical Examination: The healthcare provider may physically examine the patient and check for the appearance of nodules on the nose, neck, and head and the color of the skin over the affected area.

• Dermoscopy: It is a diagnostic test in which the healthcare provider examines the affected skin using a magnifying lens. This will help in providing a close view of the affected skin.

• Wood’s Lamp Examination: The healthcare provider examines the affected skin using ultraviolet light during this procedure. The test is performed when there is a change in skin pigmentation.

• Skin Biopsy: During this procedure, the healthcare provider will take a small sample over the affected area and send it to a laboratory for a pathological examination. The laboratory personnel will examine the sample under a microscope and conclude a definitive diagnosis.

How Is Trichofolliculoma Managed?

The treatment measures for trichofolliculoma are as follows:

• In some cases, there is no need for surgical excision of the benign tumor.

• The surgical excision of the tumor is indicated if it causes cosmetic concern to an individual.

• The permanent treatment of trichofolliculoma is surgical excision.

• Once the nodule is surgically removed, there is no recurrence rate. However, incomplete removal may result in its recurrence.

• The other treatment option is using a carbon dioxide (Co2) laser in which the nodule is burned off.

Conclusion:

Trichofolliculoma is a non-cancerous skin condition characterized by nodules on the face and neck. It is diagnosed through physical examination, dermoscopy, and skin biopsy. A complete surgical removal of the tumor can cure the condition. Complications include bleeding and infection. The prognosis of trichofolliculoma is very good.