MITF Gene Variant Linked With Fast-growing Melanomas

The gene MITF variant p.E318K may be associated with a high nevi count and fast-growing melanomas, according to a Spanish study published online ahead of print in JAMA Dermatology.¹

Researchers led by Miriam Potrony, MSc, of the University of Barcelona conducted a hospital-based, case-control study of 531 patients with melanoma with genotyped MITF p.E318K who were treated at the Melanoma Unit of Hospital Clinic of Barcelona.

The patients included 271 who had multiple primary melanoma without mutations affecting p16INK4A (wild-type p16INK4A), 191 probands from melanoma-prone families who had a single melanoma diagnosis without mutations affecting p16INK4A, and 69 probands from different families who carried CDKN2A mutations that affected p16INK4A. They were age- and sex-matched with 499 cancer-free individuals.

MITF p.E318K was found to be associated with an increased melanoma risk with results reported as odds ratio, especially in patients with MPM and high nevi count, and 2 fast-growing melanomas were detected in 2 patients with the gene variant upon digital follow-up.

Prevalence of the variant was calculated within each patient subset and was found to be 1.9% in all melanoma patients with wild-type p16INK4A, 2.6% of those with multiple primary melanoma, and 2.9% in the probands of families with p16INK4A mutations.

“Testing for MITF p16INK4A should not exclude patients with known mutations in p16INK4A,” the researchers concluded.

Reference

1. Potrony M, Puig-Butille JA, Aguilera P, et al. Prevalence of MITF p.E318K in patients with melanoma independent of the presence of CDKN2A causative mutations [published online ahead of print December 9, 2015]. JAMA Derm. doi:10.1001/jamadermatol.2015.4356.