Incidence of in situ, invasive melanoma increasing

Source: Healio.com/dermatology, June 2015

Recent study results from Denmark showed an increase in melanoma incidence, and emphasized the importance of primary prevention in children and young adults and secondary prevention in older adults.

Researchers performed data analyses between April 1, 2012 and Jan. 31, 2013. They identified cases of in situ and invasive melanoma from 1985 to 2012 in Denmark using the national Danish Melanoma Group database. There were 3,299 cases of in situ melanoma and 20,760 cases of malignant melanoma reported.

The incidence of malignant melanoma increased in men by 4.5% (95% CI, 3.6-5.3) and in women by 4.3% (95% CI, 3.5-5.2). The increase in incidence was particularly prominent in patients aged older than 60 years, with estimated annual percentage changes of 5.8% for men (95% CI, 4.7-6.8) and 4.8% in women (95% CI, 3.8-5.9). There was an increase in the incidence of thin malignant melanoma (Breslow thickness < 0.75 mm), with estimated annual percentage changes of 6.6% for men (95% CI, 5-8.2) and 6.1% for women (95% CI, 6-7.1). The incidence of superficially spreading malignant melanoma also increased, with estimated annual percentage changes of 5.2% for men (95% CI, 4.3-6.2) and 4.7% for women (95% CI, 3.9-5.7).

“We found no significant [estimated annual percentage change] in the incidence of melanomas with Breslow thickness greater than 2 mm in women, and relative ulceration rates (95% CI) declined in both sexes,” the researchers wrote.

There was a 14% increase of in situ melanoma in men (95% CI, 12.2-15.8) and an 11.6% increase in women (95% CI, 10.2-13.2). The changes in age over time were similar to those of malignant melanoma. Men had increased mortality related to malignant melanoma with an estimated annual percentage change of 0.6% (905%, 0.1-1.2), whereas women’s mortality remained stable, with an estimated annual percentage change of –0.4% (95% CI, –1 to 0.3),

“A relative increase in in situ melanoma, thin [malignant melanoma] and 5-year survival rates with a decrease in ulcerated tumors indicates that secondary interventions, such as early detection and treatment, are most likely effective,” the researchers concluded. “Future efforts should intensify primary prevention, which could be specifically aimed at young adults, adolescents, and children. Efforts in secondary prevention should be maintained and targeted at the population older than 60 years.” – by Bruce Thiel