Merkel cell carcinoma

DEFINITION

Merkel cell carcinoma is a rare type of skin cancer that usually appears as a flesh-colored or bluish-red nodule, often on your face, head or neck. Merkel cell carcinoma is also called neuroendocrine carcinoma of the skin.

Merkel cell carcinoma most often develops in older people. Long-term sun exposure or a weak immune system may increase your risk of developing Merkel cell carcinoma.

Merkel cell carcinoma tends to grow fast and to spread quickly to other parts of your body. Treatment options for Merkel cell carcinoma often depend on whether the cancer has spread beyond the skin.

CAUSES

It’s not clear what causes Merkel cell carcinoma. Merkel cell carcinoma begins in the Merkel cells. Merkel cells are found at the base of the outermost layer of your skin (epidermis). Merkel cells are connected to the nerve endings in the skin that are responsible for the sense of touch.

SYMPTOMS

The first sign of Merkel cell carcinoma is usually a fast-growing, painless nodule (tumor) on your skin. The nodule may be skin colored or may appear in shades of red, blue or purple. Most Merkel cell carcinomas appear on the face, head or neck, but they can develop anywhere on your body, even on areas not exposed to sunlight.

When to see a doctor

If you notice a mole, freckle or bump that is changing in size, shape or color, growing rapidly or bleeding easily after minor trauma, such as washing your skin or shaving, make an appointment with your doctor.