Mayo study validates melanoma test to help some patients avoid surgical biopsy

More than 100,000 people in the U.S. are expected to be diagnosed with melanoma this year — double the number of cases compared to 30 years ago, according to the American Academy of Dermatology Association. 

"Melanoma accounts for only about 2% of skin cancers, but it causes a majority of skin cancer deaths," says Alexander Meves, M.D., a Mayo Clinic dermatologist whose laboratory in Mayo Clinic's Center for Individualized Medicine works on cutting-edge methods to diagnose and treat melanoma.

In a study published in the International Journal of Dermatology, Dr. Meves and his team validated a diagnostic test they developed for melanoma, called Merlin, that combines a patient's genetic information from a skin biopsy with other characteristics to show whether they are at risk of their cancer spreading.

Dr. Meves says that typically people who are newly diagnosed with melanoma undergo a sentinel lymph node biopsy, which is an invasive surgical procedure, where some of the small round nodes that can transport cancer cells are removed and analyzed to find out if the cancer has spread from the skin. He says the Merlin assay could allow some patients at low risk of metastasis avoid having the biopsy.

"We found that the Merlin test was able to achieve a reduction of 42% of unnecessary surgeries because the melanomas of patients were identified as low-risk disease ― tumor stages 1 and 2," explains Dr. Meves. "Our data will further inform physicians, patients and insurance companies about the usefulness of the test."

The study involved 208 adult patients with primary melanoma at Mayo Clinic and West Virginia University. Patients were stratified according to their risk for nodal metastasis.

He says additional validation studies are ongoing.

Melanoma develops in the cells that produce melanin, or melanocytes. Melanin is the pigment that gives skin its color. The exact cause of melanoma is not clear, but exposure to ultraviolet radiation from sunlight or tanning lamps is known to increase the risk.

Melanoma can develop anywhere on the body, especially places exposed to the sun, including the back, legs, arms and face. Common signs of melanoma are a change in an existing mole, or the development of a new pigmented or unusual-looking growth on your skin.

"Proactive skin care can help keep your skin youthful and healthy," Dr. Meves says. "Start with skin care rule No. 1 — protect yourself from the sun. When you're outdoors, wear protective clothing and use generous amounts of sunscreen."

Funding and disclosure

Dr. Meves' study was funded by grants from the National Cancer Institute and the National Center for Advancing Translational Sciences, as well as Mayo Clinic's Center for Individualized Medicine, Mayo Clinic Cancer Center and the Fifth District Eagles Cancer Telethon.

Dr. Meves reports a financial interest in the test being developed by SkylineDx. Mayo Clinic has reviewed this relationship and taken appropriate steps to protect the scientific integrity of the research.

Learn more

Learn more about melanoma and find a melanoma clinical trial at Mayo Clinic.

A version of this article was originally published on the Mayo Clinic Center for Individualized Medicine blog.