Cylindroma - Clinical Features, Histopathological Features, Diagnosis, and Treatment

What Is Cylindroma?

Cylindroma is a benign skin tumor that occurs mostly on the head and neck. It is called by the name cylindroma because it is a tumor comprising nests of cells that looks like a cylinder in cross-section. The origin of cylindroma is still controversial as it can be either an eccrine or apocrine origin. Clinically they are presented either as solitary or multiple tumors over the head and neck. Solitary cylindromas are not inherited and occur sporadically. On the other hand, multiple tumors are seen as autosomal dominantly inherited. Malignant cases of cylindromas are very rare. The types of cylindroma include:

• Dermal Cylindroma - Benign tumor affecting the skin (scalp and forehead).

• Adenoid Cystic Carcinoma - A malignant tumor of the salivary gland.

What Are the Other Names of Cylindroma?

Cylindroma is also referred to by the following names:

• Dermal Eccrine Cylindroma: Benign neoplasm of eccrine sweat glands present in the head and neck.

• Spiegler’s Tumor: Tumors that are derived from skin appendages like sweat gland tumors and hair follicle tumors.

• Turban Tumor: Multiple cylindromas that affect the scalp.

• Adenoid Cystic Carcinoma: A malignant tumor of the salivary gland that is so-called cylindroma because of its histopathological features.

• Tomato Tumor: It is so-called because the lesions of multiple cylindromas appear as masses of pink, red, or blue nodules that look like small tomatoes.

What Causes Cylindroma?

Cylindroma occurs either in sporadic or familial forms. Sporadic forms of cylindroma appear as solitary lesions. These sporadic (non-hereditary) cylindromas express MYB-NFIB (MYB proto-oncogene — nuclear factor I/B) gene fusion transcripts. This MYB-NFIB fusion encourages the neoplastic process. Sometimes overexpression or activation of MYB oncogene alone can accelerate the formation of dermal cylindromas.

Familial cylindromatosis syndromes like Brooke-Spiegler syndrome (BSS) occur due to mutation in CYLD (CYLD Lysine 63 Deubiquitinase) tumor suppressor gene. CYLD mutation occurs in an autosomal dominant pattern. In BSS, the CYLD mutation occurs with variable phenotypic expressions.

Who Is More Likely to Be Affected by Cylindroma?

Cylindromas are rare tumors, and the exact incidence of this tumor is unknown. There is no racial disparity seen in cylindroma. Solitary cylindroma usually affects middle-aged and elderly individuals. At the same time, multiple and inherited cylindromas are seen affecting early adulthood, and they progress in size and number throughout life. Females are more commonly affected by cylindroma than men. Female to male ratios of 6:1 and 9:1 are reported in certain studies.

What Does Cylindroma Look Like?

Clinically cylindroma can either be presented as solitary or multiple lesions. Solitary lesions are usually sporadic and are not hereditary. At the same time, multiple cylindromas are hereditary and exhibit autosomal dominantly inherited patterns. Cylindromas are generally benign, and they affect the head and neck region (mostly scalp). They also do occur in the trunk and extremities.

The following are the clinical presentations of cylindroma.

• They are usually slow-growing, rubbery solitary pink or red dermal nodules that grow with an average of 1 cm in size. The solitary lesions usually exhibit no symptoms, but sometimes they are painful too.

• Multiple or inherited variants of cylindroma occur shortly after puberty. Clinically they appear as multiple rounded nodules of sizes ranging from a few millimeters to larger than 6 cm. Lesions of multiple cylindromas grow slowly, with some extra lesions developing over time.

Clinical Features of Turban Tumor:

• In the dermal cylindroma of the scalp (turban tumor), multiple pinkish, firm nodules are seen covering the forehead and entire scalp. These firm nodules coalesce on the scalp exhibiting a turban-like appearance. The size of these tumors may vary from several millimeters to 5 cm in diameter; with time, the size of the tumor increases in size and number.

Clinical Features of Adenoid Cystic Carcinoma:

• Adenoid cystic carcinoma is histologically similar to cylindroma. It is a rare cancer form that develops commonly in salivary glands or the regions of the head and neck.

• The lesions of salivary glands initially appear as painless, slow-growing masses seen below the mucosal lining of the mouth, skin, or face.

• Numbness of upper jaw, face, palate, or tongue.

• Dull pain and difficulty swallowing.

• Hoarseness of voice.

• Paralysis of the facial nerve in severe condition.

If you are observed with any of the above changes, then do consult your doctor to get a clear idea of the condition.

What Are the Histopathological Features of Cylindroma?

The histopathological features of cylindroma include,

• Under microscopic examination, cylindroma exhibit nests of basaloid cells arranged in a jigsaw or mosaic pattern.

• The lobules of the tumor are encircled by a prominent red basement membrane-like structure.

• It consists of nests of cells that appear cylindrical in cross-section.

• Each lobule exhibits two types of cells. It includes.

1. 1. Undifferentiated palisading epithelial cells at the periphery with small dark nuclei.
   2. Increasingly differentiated ductal cells that are centrally located with pale nuclei.

• Nodular deposits of red material are seen inside the lobules and in the well-formed ducts.

How Is Cylindroma Diagnosed?

Cylindroma can be diagnosed by the following diagnostic measures. It includes;

1. Laboratory Studies: Various tests like reverse-transcriptase polymerase chain reaction (RT-PCR), whole-exome sequencing, fluorescence in situ hybridization, immunohistochemistry, etc., are used in diagnosing benign cylindroma in the breast. Expression of MYB and GATA3 (a transcription factor) helps differentiate between adnexal carcinomas and cylindroma of the breast and salivary gland metastases.
2. Imaging Studies: Dermatoscopy is used in examining cylindromas. In dermatoscopy, a dermatoscope (powerful lighting system) and a high-quality magnifying lens are used. This examines the skin surface using skin microscopy. The images obtained through dermoscopy are archived using computer software, thus allowing for better diagnosis. MRI (magnetic resonance imaging) is used in cylindromas of the scalp with malignant potential to detect any underlying intracranial invasion.
3. Biopsy: A skin biopsy involves the removal of a small amount of tissue from the affected area and is sent for pathological analysis. The obtained tissue sample is stained with ordinary hematoxylin and eosin (H and E) and then examined under light microscopy to diagnose cylindroma. This examination reveals the presence of nests of basaloid cells arranged in a jigsaw or mosaic pattern.

How Is Cylindroma Treated?

Cylindroma can be treated by the following treatment modalities:

• Surgical Care: Surgical excision is carried out in case of solitary lesions. The other different methods that help in removing the solitary lesion include;

1. 1. Curettage: A procedure where the affected skin surface is scraped using a curette.
   2. Electrodesiccation: A procedure using electric current to remove skin lesions.
   3. Cryotherapy: A procedure where cold liquid or an instrument known as a cryoprobe is used to freeze and destroy the abnormal tissue.

In cases of small cylindroma, a carbon dioxide laser may be used. Extensive plastic surgery is required in the cases of multiple cylindromas.

• Medical Care: Other than surgery, therapeutic options like inhibition of NF-kappa B (nuclear factor kappa light chain enhancer of activated B cells) is highly helpful in managing CYLD cutaneous syndrome.

• Long-Term Monitoring: Follow-up of patients is highly necessary, especially in cases of multiple cylindromas, since it tends to develop new lesions. Recurrence is seen in some cases after surgical treatment of cylindroma, so follow-up of patients at regular intervals may help in avoiding and treating recurrent lesions.

What Are the Differential Diagnoses of Cylindroma?

The differential diagnoses of cylindroma include the following,

• Basal cell carcinoma (skin cancer that develops in the basal cells).

• Microcystic adnexal carcinoma (malignant sweat gland tumor).

• Spiradenoma (benign dermal neoplasm that originates from sweat glands).

• Trichoepithelioma (benign skin lesion that originates from the hair follicles).

• Pilar cyst (type of dermal cyst).

• Poroma (a benign adnexal tumor that originates from the duct of sweat glands).

• Salivary gland neoplasms.

• Blue nevi (a benign type of mole).

Conclusion:

Cylindroma is a rare benign skin tumor that most commonly affects the head and neck region. It can be presented either as solitary or multiple lesions. Solitary lesions are usually sporadic and not inherited, whereas multiple cylindromas exhibit autosomal dominantly inherited patterns. It can develop into malignant cases very rarely. Doctors often go with surgical treatment as the best option to treat cylindroma. There is no effective systemic treatment for cylindroma.