Signs and Symptoms of Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) usually starts on areas of skin exposed to the sun, especially the face, neck, arms, and legs, but it can occur anywhere on the body. It often first appears as a single pink, red, or purple bump that is not usually painful. Sometimes the skin on the top of the tumor might break open and bleed.

These tumors can grow quickly. They might spread as new lumps in the surrounding skin. They might also reach nearby lymph nodes (small collections of immune system cells throughout the body). Over time, the lymph nodes might grow large enough to be seen or felt as lumps under the skin (usually in the neck or under the arm).

Merkel cell carcinoma is not common, and it can look like many other, more common types of skin cancer or other skin problems when it first appears. Because of this, doctors do not usually suspect MCC at first, and the diagnosis is often made only after the tumor is biopsied.

It’s very important to have any new, growing, or changing lumps, bumps, or spots on your skin checked by a doctor as soon as possible so that the cause can be found and treated, if needed. The earlier any type of skin cancer is found, the more likely it can be treated effectively.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master's-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: April 13, 2015 Last Revised: May 23, 2016

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