Mid‐term trends and recent birth‐cohort‐dependent changes in incidence rates of cutaneous malignant melanoma in Italy

Abstract

In Oceania, North America and north‐western Europe, after decades of increase, cutaneous malignant melanoma (CMM) rates began to stabilise or decline before 2000. Anecdotal evidence suggests that the reversal of the incidence trend is extending to southern Europe. To obtain a formal confirmation, this nationwide study from Italy investigated the incidence trends by birth cohort. Twenty‐one local cancer registries covering a population of 15 814 455 provided incidence data for primary CMM registered between 1994 and 2013. Trends in age‐standardised rates were analysed using joinpoint regression models and age‐period‐cohort models. Age‐standardised incidence showed a consistent increase throughout the period (estimated annual percent change, 3.6 [95% confidence interval, 3.2‐4.0] among men and 2.5 [2.0‐3.1] among women). This pattern was confirmed by a sensitivity analysis with removal of low‐risk populations of southern Italy. The rates, however, showed a stabilisation or a decrease in men and women aged below 35. Using the cohort of 1949—the median cohort with respect to the number of cases for both genders—as a reference, the incidence rate ratio increased for successive cohorts born until 1973 (women) and 1975 (men), and subsequently tended to decline. For the most recent cohorts in both genders, the risk of disease returned to the level of the cohort of 1949. The changes observed in the latest generations can be interpreted as the earliest manifestations of a birth‐cohort‐dependent incidence decrease. Our study adds to previous data indicating that the reversal of the long‐term upward incidence trend of CMM is extending to southern Europe.

Descriptive epidemiology of cutaneous melanoma – A treasure for generating hypotheses

“…Among people older than 34 years, annual incidence rates continuously increased until 2018. This age- and time-dependent trend pattern may be explainable by a birth cohort effect that has also been shown in several other populations in European mainland [ 2 , 3 ], Australia [4] , and the U.S. [5] . Memon et al.…”

The relative contribution of the decreasing trend in tumour thickness to the 2010s increase in net survival from cutaneous malignant melanoma in Italy: a population‐based investigation*

“…Firstly, cancer registration in Italy has been introduced irregularly both in time and space. The implications of, and the potential solutions to, this drawback are discussed in another article 29 . Restricting the analysis to a smaller number of registries with comparable time periods of registration, as we did in this study, is one of the most commonly used approaches 59 …”

“…Over the past three decades, the incidence of CMM in Italy has constantly increased 29 . Several local studies have already suggested that this trend has been more pronounced for thin CMM 30,31 .…”

“…Over the past three decades, the incidence of CMM in Italy has constantly increased. 29 Several local studies have already suggested that this trend has been more pronounced for thin CMM. 30,31 As found elsewhere, the reduction in tumour thickness has been accompanied by a consistent increase in 5year survival rates.…”

Environmental effects of stratospheric ozone depletion, UV radiation, and interactions with climate change: UNEP Environmental Effects Assessment Panel, Update 2021

“…In Canada [ 204 ], Italy [ 205 ], and England [ 206 ] there is evidence that the incidence of melanoma is stabilising in younger age groups. The incidence in children aged 10–19 in the United States also decreased from 2000 to 2015 [ 207 ].…”