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Merkel Cell Carcinoma

(Neuroendocrine Skin Carcinoma; Trabecular Cell Carcinoma; APUDoma of the Skin)


Gregory L. Wells

, MD, Ada West Dermatology and Dermatopathology

Last full review/revision Jan 2021| Content last modified Jan 2021
Click here for the Professional Version

Merkel cells are normal cells in the epidermis Epidermis The skin is the body’s largest organ. It serves many important functions, including Protecting the body against trauma Regulating body temperature Maintaining water and electrolyte balance Sensing... read more Epidermis (the outer layer of the skin). These cells mostly function as touch receptors and they produce certain hormones. Merkel cell carcinoma arises from uncontrolled growth of cells in the skin that share some characteristics with normal Merkel cells.

Merkel cell carcinoma is diagnosed at an average age of 75. Merkel call carcinoma also affects younger people whose immune system is weakened. Sun exposure increases the risk, as does having another cancer. The Merkel cell polyomavirus may be a contributory factor. This cancer commonly spreads to the lymph nodes.

Symptoms of Merkel Cell Carcinoma

The cancer is typically a firm, shiny, flesh-colored or bluish red bump. Cancers tend to grow rapidly without causing pain or tenderness. Although Merkel cell carcinoma can affect any part of the skin, it is most common on skin that has been chronically exposed to sunlight (for example, the face and arms).

Diagnosis of Merkel Cell Carcinoma

  • Biopsy

A biopsy Biopsy Doctors can identify many skin disorders simply by looking at the skin. A full skin examination includes examination of the scalp, nails, and mucous membranes. Sometimes the doctor uses a hand-held... read more Biopsy is done to confirm the diagnosis of Merkel cell carcinoma. During this procedure, a small piece of skin is removed and examined under a microscope.

In most people, the cancer has already spread by the time the diagnosis has been made, so the prognosis of Merkel cell carcinoma is poor.

Prevention of Merkel Cell Carcinoma

Treatment of Merkel Cell Carcinoma

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • A resource to help people find access to Merkel cell specialists and other patient resources

See the following sites for comprehensive information about Merkel cell carcinoma, including detection, prevention, treatment options, and other resources:

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
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