Study Finds Merkel Cell Carcinoma Incidence Has Increased Since 2000

The number of reported merkel cell carcinoma (MCC) cases has increased 95% between 2000 and 2013, according to a study published in the Journal of the American Academy of Dermatology and presented at the American Academy of Dermatology 2018 Annual Meeting in San Diego, California.

“MCC is rare, but our research shows that it’s becoming less rare,” Paul Nghiem, MD, PhD, FAAD, head of the division of dermatology and George F. Odland Endowed Chair in Dermatology at the University of Washington in Seattle, said in a press release. “Compared to melanoma, MCC is much more likely to be fatal, so it’s important for people to be aware of it.”

MCC is a rare type of skin cancer in which only a few thousand patients are diagnosed with each year. However, MCC is extremely aggressive, resulting in higher mortality rates than the more common skin cancer melanoma. Nghiem and his team of researchers recognized an increase in cases of melanoma over the years and assumed that MCC cases were increasing, as well.

The data show that MCC cases increased 95%, while melanoma cases increased only 57% from 2000 to 2013. The incidence of other cancerous tumors only grew 15%. The team of researchers estimate 3200 cases of MCC will arise in 2025.

This type of skin cancer is more likely to affect patients with a prior history of cancer, men, Caucasians and people older than 50.

“We believe the aging of the US population is likely driving the increase in MCC, as this cancer is much more prevalent in older individuals,” Dr. Nghiem explained, adding that weakened immunity in this population may play a role in the disease. He included in his statement that MCC incidence rates increased 10-fold between the ages 40 and 44, and 60 and 64, with another 10-fold increase between 60 and 64 and over 85.

Like all types of skin cancers, MCC is caused by unprotected exposure to ultraviolet light. Nghiem recommends avoiding excessive exposure to UV light by sitting in the shade, wearing clothing that covers the skin, and wearing a broad-spectrum, water-resistant sunscreen with an SPF of 30 or higher.

MCC treatment is most successful when detected early on. The cancer can be treated during the early stages; however, it is important to recognize that the cancer is aggressive and can metastasize quickly.

While melanoma appears on the skin as a dark mole, MCC appears as a firm lump that is red, purple, or skin-colored. Many patients can mistake MCC for a cyst or folliculitis. MCC lesions are not tender to the touch like bumps caused by those conditions.

“If you notice a new, unusual growth, especially one that looks different from the other spots on your skin or one that is growing quickly, see a board-certified dermatologist for diagnosis,” Dr. Nghiem concluded. “If you do have MCC, it’s important to receive care from a qualified team of physicians that understands how to manage this disease, and your dermatologist can help ensure you get the care you need.”