Merkel cell carcinoma often appears on areas of the body that receive the most sunlight. This includes the face, neck, and hands. This article will describe the common symptoms of Merkel cell carcinoma and what to do if you notice a new skin growth.

Frequent Symptoms

The most common symptom of Merkel cell carcinoma is a painless lump on the skin. The lump can easily be mistaken for a benign skin condition like a pimple, sore, or insect bite.

Merkel cell carcinoma is most often found on areas of the skin that receive the most sun exposure, such as the face and neck. It is commonly found in individuals with fair skin who are over age 50. Merkel cell carcinoma may present differently depending on your age and skin color. The cancerous growth is more likely to appear on the legs in African Americans and the torso in younger individuals. 

A Merkel cell carcinoma lump usually has the following characteristics:

Being pink, red, or purple in colorHaving a shiny, pearl-like appearanceBeing fast growingBeing scaly and slightly raisedHaving a dome shape 

Rare Symptoms

While Merkel cell carcinoma usually appears as a painless lump on the skin, it may present with other rare symptoms:

Pain: Rarely, the growth may feel sore or tender when pressed. Itching: Most people do not experience pain or itching, but if a sore starts to itch, it’s best to see your dermatologist (a medical doctor specializing in conditions of the skin, hair, and nails) to have them evaluate it.   Bleeding: Occasionally, a growth caused by Merkel cell carcinoma can open up and bleed. Enlarged lymph nodes: Merkel cell carcinoma is a fast-growing cancer that can spread to nearby lymph nodes and cause them to become enlarged. They often appear as lumps under the skin, and usually present on the neck or under the arms.  

Complications

Merkel cell carcinoma is an aggressive form of skin cancer that can quickly spread and lead to complications. When left untreated, Merkel cell carcinoma spreads, or metastasizes, to other tissues and organs in the body. Once cancer spreads to additional areas of the body, it becomes much more difficult to treat.

Because Merkel cell carcinoma is fast growing and easily mistaken for benign conditions, it is likely to metastasize quickly. A 2017 study found that about 30% of patients already had metastases at the time they were diagnosed with Merkel cell carcinoma. 

Merkel cell carcinoma has a relatively high risk of recurring, or coming back, after it has been treated and can be fatal. 

When to See a Doctor/Go to the Hospital

Merkel cell carcinoma can be difficult to spot, so it is important to see your dermatologist for an annual skin check. Never hesitate to see your doctor if you notice a new skin growth, especially if the growth appears to be getting bigger or changing quickly. 

You should also perform monthly skin self-checks. To spot a worrisome growth, use the following AEIOU guidelines recommended by the Skin Cancer Foundation:

A for asymptomatic: The growth is usually not painful. E for expanding: The growth expands quickly. I for immunosuppressed: People with compromised immune systems are at higher risk. O for older: Individuals over age 50 are at higher risk of developing Merkel cell carcinoma. U for UV (ultraviolet) rays: A growth is more likely to develop on an area of the body that receives the most sun exposure.  

Summary

Merkel cell carcinoma is a rare and aggressive form of skin cancer. The most common symptom is a painless lump on the skin. This lump is usually red or purple in color, appears shiny, and is dome shaped. Merkel cell carcinoma is fast growing and may change its appearance quickly. See your dermatologist every year and anytime you notice a new skin growth that concerns you. 

A Word From Verywell

If you have noticed a new skin growth and suspect it may be Merkel cell carcinoma, you are likely feeling afraid and overwhelmed. That’s a normal response, and the best step you can take is to see your doctor right away. The earlier you are diagnosed and treated, the better chance you will have for effective treatment and a good prognosis. 

Stage 0: Also known as carcinoma in situ, stage 0 describes the finding of abnormal Merkel cells in the top layer of skin. These cells are not yet cancerous but are at risk of becoming malignant and spreading. Stage I: The cancerous tumor is 2 centimeters wide or smaller. Stage IIA: The tumor is wider than 2 centimeters but less than 5 centimeters. Stage IIB: The tumor has spread to nearby tissues but not lymph nodes. Stage IIIA: The tumor has spread to nearby lymph nodes. Stage IIIB: The tumor has spread to nearby tissues, a lymph node can be felt during a physical exam, and cancer cells are found in the lymph node. Stage IV: The tumor has spread to distant areas of the body, including the liver, lungs, bones, or brain.