Legendary singer-songwriter Jimmy Buffett died Sept. 1 after battling Merkel cell carcinoma, a form of skin cancer that is diagnosed in fewer than 3,000 Americans each year. The announcement was a shock to his fans on the unofficial last weekend of summer. While skin cancer is the most common form of cancer, according to the American Cancer Society, few people have heard of Merkel cell carcinoma.

German scientist Friedrich Merkel first identified this type of cancer in 1875, according to CNN. Merkel cells, a type of neuroendocrine cell, are a found in the top layer of the skin close to the nerve endings of the skin that are responsible for the sense of touch.

When the cells grow out of control, this develops into Merkel cell carcinoma. Although the cause is unknown, scientists believe it has something to do with UV light exposure, weakened immune system due to disease or age, or the Merkel cell polyomavirus (MCV) — that just about everyone gets as a child but usually with no symptoms.

Merkel cell carcinoma most often occurs on areas of the body that are most exposed to the sun, such as the face, neck, and arms. But it can also be found inside the nose or esophagus. It looks like a raised red or purple cyst, unlike melanoma, another serious cancer, that is usually dark in appearance.

Buffett, 76, had been living with the cancer for four years. Experts say that if it is detected early there is a 75% chance of living at least five years after diagnosis. But if it spreads beyond the skin, the five-year survival rate drops to 24%, says the American Cancer Society (ACS).

Men are twice as likely to get Merkel cell carcinoma than women, according to CNN. About 90% of sufferers are white and about 80% are over 70 years of age. The risks may be in proportion to how much sun damage a person has during his or her lifetime.

Treatment includes biopsy and removal of the cancer in its early stages, and a biopsy of a nearby sentinel lymph node to see if the cancer has spread. The ACS says that cancer is found in the lymph nodes of one in three people with Merkel cell carcinoma.

Other treatment options include chemotherapy, and/or radiation depending on the stage, and possibly immunotherapy to help the body get rid of the cancer cells.

HOW TO PROTECT YOURSELF FROM SKIN CANCER

While there is no way to prevent MCV, the virus linked to Merkel cell carcinoma, there are ways to protect yourself against this form of skin cancer and against skin cancer in general. Since early detection is crucial, examine your skin regularly and see your dermatologist at least annually. The American Society of Dermatology offers free skin cancer screenings across the country.

The Centers for Disease Control and Prevention suggests that boosting your immune system by getting proper sleep, avoiding alcohol and smoking, maintaining a healthy weight, eating a balanced diet and getting sufficient exercise may help prevent cancer.

You should also protect yourself against damaging ultraviolet rays by never using a tanning bed, wearing a hat and sunglasses and using a sunscreen with an SPF of 30 or higher when outdoors — even when it is cloudy. The Environmental Working Group (EWG), a nonprofit organization that has been testing sunscreens for years, recommends lotion sunscreens over sprays.

EWG researchers advise that consumers should avoid all spray and powder sunscreen products. In May, the organization released its annual Guide to Sunscreens. The best-scoring recreational sunscreens on EWG’s list contain the mineral-based active ingredients zinc oxide, titanium dioxide or both, since they have fewer health concerns and offer good sun protection. Zinc oxide, especially, provides good broad-spectrum and is stable in the sun.

Shoppers can download EWG’s Healthy Living App to get ratings and safety information on sunscreens and other personal care products. EWG’s sunscreen label decoder can also help consumers looking for safer sunscreens.