Trends in three major histological subtypes of cutaneous melanoma in the Netherlands between 1989 and 2016.

Background: Time trend analysis of cutaneous melanoma (CM) mortality in fair skin populations shows both a gradual decrease and/or an increase. To explain these differences, we analyzed long-term time trends in the incidence of the most common histological subtypes of CM: superficial spreading melanoma (SSM), lentigo maligna melanoma (LMM), and nodular melanoma (NM).

Methods: Using data from the Netherlands Cancer Registry and Statistics Netherlands, the number and rates of cases diagnosed with SSM, LLM, and NM from 1989 to 2016 were analyzed by age, calendar period, and birth cohort of people born in successive periods from 1925 to 1973.

Results: Primary CM was diagnosed in 52,000 men and 66,588 women in the study period. The annual age-standardized incidence rate increased three-fold from 14 to 42 per 100,000 person-years. The most common subtype was SSM (50%), followed by LMM (23%) and NM (14%). Age-specific subtype rates showed an upward trend over time for both men and women. Younger birth cohorts had higher rates of SSM and LMM diagnosis than older birth cohorts. This birth cohort pattern was not observed for NM.

Conclusions: We observed a strong increase in the melanoma epidemic curves in the light-skinned Dutch population over the last three decades. This increase is explained by younger generations having higher rates of SSM and LMM than older generations.