Age and Cohort Trends of Malignant Melanoma in the United States

Abstract

The incidence of malignant melanoma in the United States is increasing, possibly due to changes in ultraviolet radiation (UVR) exposure due to lifestyle or increased awareness and diagnosis of melanoma. To determine if more recent birth cohorts experience higher rates of melanoma as they age, we examined age and birth cohort trends in the United States stratified by anatomic site and cancer type (in situ vs. malignant) of the melanoma diagnosed from 1975–2017. Poisson regression of cutaneous melanoma cases per population for 1975–2017 from the Surveillance, Epidemiology, and End Results (SEER) cancer registries was used to estimate age adjusted incidence for five-year birth cohorts restricted to Whites, ages 15–84. The rate of melanoma incidence across birth cohorts varies by anatomic site and sex. Melanomas at all anatomic sites continue to increase, except for head and neck melanomas in men. Much of the increase in malignant melanoma is driven by cases of thin (<1.5 mm) lesions. While increased skin exams may contribute to the increased incidence of in situ and thin melanoma observed across birth cohorts, the shifts in anatomic site of highest melanoma incidence across birth cohorts suggest changes in UVR exposure may also play a role.

Not Your Mother’s Melanoma: Causes and Effects of Early Melanoma Diagnosis

“…Using the SEER registry, Lashway et al (2021) found that CM incidence increased with age between 1975 and 2017. After adjusting for age and stratifying groups into 5-year birth cohorts, these researchers discovered significantly greater melanoma incidence at older ages [ 15 ]. Paulson et al (2019) further this age-based dichotomy when reporting that CM incidence decreased in populations under 40 years old between 2006 and 2015 but increased in people 40 years old and over during the same time [ 16 ].…”

“…The steep increase in biopsy and diagnosis rates of thinner melanomas, in particular, has augmented the total number of tumor cases identified [ 4 , 9 , 18 , 19 , 20 ]. Critical contributors to these observed trends include increased skin cancer awareness by patients and providers and efforts targeting primary and secondary prevention at the local and national levels [ 15 , 18 , 20 ]. Before professional associations like the American Academy of Dermatology endorsed melanoma screenings, CM diagnosis generally revolved around the presence of distinguishable macroscopic findings like size and ulceration; as a result, the disease was often identified during its later stages [ 15 ].…”

“…The development of national public education campaigns has encouraged sun-protective behaviors and taught individuals—particularly school-aged children—about the significance of early CM detection [ 22 ]. Adoption and expansion of these public health initiatives, broadening media exposure, and advertisements of preventative modalities by pharmaceutical companies have heightened melanoma awareness within populations in the United States and other countries [ 8 , 15 , 22 ]. Australia, for example, implemented heavily-publicized, statewide campaigns emphasizing the importance of sun safety and early melanoma detection in the early 1980s.…”

Predictive accuracy of elevated mitotic rate on lymph node positivity and recurrence in thin melanomas

“…A clear understanding of the prognostic factors for malignant cutaneous melanoma is becoming increasingly paramount as its incidence continues to rise in the United States (1). Strong evidence has demonstrated that greater Breslow thickness and ulceration are correlated with melanoma-specific mortality (MSM), resulting in their inclusion in the staging system.…”

Shared Gene Expression and Immune Pathway Changes Associated with Progression from Nevi to Melanoma

“…Solar ultraviolet radiation (UVR) exposure remains the major environmental risk factor for developing CMM. Despite public health initiatives that have promoted sun protection, the incidence of CMM continues to increase, with much of the increased incidence driven by thin CMM [ 1 , 2 ]. According to recent predictions from the American Cancer Society, an estimated 106,110 new cases of invasive melanoma and 101,280 cases of melanoma in situ will be diagnosed in the US in 2021 [ 3 ].…”