WEDNESDAY, May 1, 2024 -- Melanoma incidence in Denmark increased during 1999 to 2011, with no change in mortality, according to a study published online April 24 in the British Journal of Dermatology.

Jesper Bo Nielsen, Ph.D., from the University of Southern Denmark in Odense, and colleagues examined factors that may influence melanoma incidence and mortality in Denmark in a register study based on comprehensive national pathology and mortality databases for 1999 to 2019. Melanocyte-related diagnoses and mortality were investigated in a population of 5.5 million.

Overall, 1,434,798 biopsies were taken from 704,682 individuals. The researchers found that the incidence of invasive melanoma increased by 87 percent during 1999 to 2011 among men and women. The incidence increased 9 percent in men but remained unchanged in women during the subsequent period. The incidence of melanoma in situ increased by 476 and 357 percent in men and women, respectively, during the study period; for atypical melanocytic lesions, increases were 1,928 and 1,686 percent, respectively. From 1999 to 2011, biopsy rates increased 153 percent for men and 118 percent for women, then decreased 20 and 22 percent, respectively, during the subsequent period. Year-to-year variation was seen in mortality, with no significant time trend for men or women. During the last 30 years, no evidence of increased ultraviolet exposure was seen.

"The findings of the present study indicate that changes in melanoma incidence may be explained by the interaction among sun exposure, the propensity to remove suspected melanoma lesions, lowered diagnostic thresholds, and overdiagnosis," the authors write.