SAN DIEGO — According to data from the
“The incidence of melanoma seems to have continued to go up since the early 1990s,” David E. Kent, MD, a dermatologist at Skin Care Physicians of Georgia, Macon, said at the annual Cutaneous Malignancy Update. “The death rates have been flat and may have slightly decreased.”
In 2024, the ACS estimates that about 100,640 new melanomas will be diagnosed in the United States (59,170 in men and 41,470 in women), and about 8,290 people are expected to die of melanoma (5,430 men and 2,860 women). Meanwhile, the lifetime risk of melanoma is about 3% (1 in 33) for Whites, 0.1% (1 in 1,000) for Blacks, and 0.5% (1 in 200) for Hispanics. In 2019, there were an estimated 1.4 million people in the United States living with cutaneous melanoma, and the overall 5-year survival is 93.7%.
Epidemiologic studies show an increase in melanoma incidence, primarily among White populations. “This is believed to be due to sun exposure, changes in recreational behaviors, and tanning bed exposures,” said Dr. Kent, who holds a faculty position in the department of dermatology at the Medical College of Georgia, Augusta. Increased surveillance and diagnosis also play a role. In the medical literature, annual increases in melanoma incidence vary from 3%-7% per year, “which means that the rate is doubling every 10-20 years,” he said, noting that annual melanoma costs are approximately $3.3 billion.
While incidence rates are lower in non-White, non-Hispanic populations, poor outcomes are disproportionately higher in persons of color, according to a 2023 paper. Black individuals present at diagnosis with more advanced stage disease and are 1.5 times more likely to die from melanoma, he said, while Hispanics are 2.4 times more likely to present with stage III disease and 3.6 times more likely to have distant metastases. Persons of color also have higher rates of mucosal, acral lentiginous, and subungual melanoma.
Risk Factors
Known genetic risk factors for melanoma include having skin types I and II, particularly those with light hair, light eyes, and freckling, and those with a family history have a twofold increased risk. Also, up to 40% of genetic cases are from inherited mutations in CDKN2A, CDK4, BAP1 and MCR1. Other genetic-related risk factors include the number and size of nevi, having atypical nevus syndrome, DNA repair defects, large congenital nevi, and a personal history of melanoma.
Dr. Kent said that genetic testing for melanoma is warranted for individuals who meet criteria for the “rule of 3s.” He defined this as three primary melanomas in an individual, or three cases of melanoma in first- or second-degree relatives, or two cases of melanoma and one pancreatic cancer or astrocytoma in first or second-degree relatives, or one case of melanoma and two of pancreatic cancer/astrocytoma in first- or second-degree relatives.
The main environmental risk factor for melanoma is exposure to ultraviolet radiation. Individuals can track their UV exposure with a variety of wearable devices and apps, including SunSense One Digital UV Tracker, the SunSense App, the UV Index Widget, the SunSmart Global UV App, the SunKnown UV light photometer, and the EPA’s UV Index Mobile App. Other environment-related risk factors include having a high socioeconomic status (SES), being immunosuppressed, as well as exposure to heavy metals, insecticides, or hormones; and ones distance from the equator.
In a study published in 2023, researchers investigated the risk factors associated with first and second primary melanomas in 38,845 patients who were followed in Australia between 2011 and 2018. During a median follow-up of 7.4 years, 1212 patients (3.1%) had a single primary melanoma diagnosis and 245 (0.6%) had a secondary primary melanoma diagnosis. The researchers found that second melanomas were more likely than first melanomas to be in situ; for invasive tumors, second melanomas were more likely to be thin (defined as 1 mm or less) than first melanomas. In addition, having many self-reported moles at age 21 years was more strongly associated with second melanomas compared with first melanomas (hazard ratio, 6.36 vs 3.46, respectively; P = .01), as was having a high genetic predisposition (HR, 3.28 vs. 2.06; P = .03). Second melanomas were also more strongly associated with a history of multiple skin cancer excisions (HR, 2.63 vs 1.86; P = .05).
Dr. Kent noted that while sunscreen use protects against melanoma, a National Ambulatory Medical Care Survey in 2014 found that internists and pediatricians mentioned sunscreen at fewer than 0.1% of visits — even those with patients who have a diagnosis of skin disease. “Physicians need to do better,” he said at the meeting, which was hosted by the Scripps Cancer Center. “We as dermatologists have work to do to help educate them.”
Dr. Kent reported having no relevant disclosures.