Cases of Rare Skin Cancer on the Rise

Increase in Merkel cell carcinoma cases outpaces the rate of melanoma.

Melanoma is known to be the most deadly, aggressive type of skin cancer, affecting tens of thousands of individuals each year; however, a lesser known form of deadly skin cancer is becoming more prevalent.

A new study published by the Journal of the American Academy of Dermatology and presented at the American Academy of Dermatology 2018 Annual Meeting discussed the growing prevalence of Merkel cell carcinoma (MCC).

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

Due to the increasing prevalence of melanoma, the authors hypothesized that MCC cases were also on the upswing. Through analyzing data from the National Cancer Institute’s SEER-18 registry, they discovered that MCC cases were skyrocketing.

From 2000 to 2013, the number of MCC cases increased 95% compared with 57% for melanoma and 15% for other cancers, according to the study.

Based on current trends, the researchers project that MCC cases will swell from nearly 2500 cases in 2013 to more than 3200 in 2025, according to the study.

MCC is more common among patients with previous skin cancers, men, Caucasians, and patients 50 years and older. The authors noted that age is a main driver of MCC, with rates increasing 10-fold between aged 40 and 44 years and another 10-fold between ages 60 to 64 years and among those 85 and older.

“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 said.

The authors also suggest that diminished immune function among the aging population may play a role.

Although immunotherapy has resulted in better survival rates, MCC is likely to metastasize and become fatal, which makes prevention key, according to the study.

MCC is linked to the Merkel cell polyomavirus, which is commonly found on the skin and other surfaces. A majority of individuals do not develop MCC after exposure to polyomavirus; however, if a patient’s immune function is limited, they may be at a higher risk of developing MCC.

MCC risk also associated with exposure to ultraviolet light, which makes having a comprehensive sun protection plan more important, according to the study.

The study authors stressed the importance of sun protection and being vigilant about skin cancer screenings.

“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,” Dr Ngheim said.