The incidence of skin melanoma in Gran Canaria (Canary Islands, Spain) is lower than expected in Southern Europe despite high-risk environmental conditions: an island-wide cross-sectional study

Abstract

Background: The Canary Islands are a leading European touristic destination. The ultraviolet index (UVI) in the region is the highest in Spain, and similar to indexes registered in Australia and New Zealand, which hold the highest incidence of skin melanoma worldwide. Yet according to cancer registry data, the incidence in the Canary Islands in the late 1990s was the lowest in Spain (among the lowest in Europe) and about six times lower than in New Zealand. Purpose: To analyze the incidence rates of skin melanoma in Gran Canaria island between 2007 and 2018. Methods: The study was based in the two centres of the Canary Islands’ Healthcare Service centralizing melanoma care in Gran Canaria. We analyzed crude and age-standardized (ASR) incidence rates of invasive cutaneous melanoma for the period 2007–2018 following the inclusion criteria of the International Agency for Research on Cancer (IARC). Clinical and histological characteristics of melanoma patients were assessed. Results: A total of 1058 patients were included. The incidence rates obtained matched the latest available Canary Islands’ cancer registry data, confirming its reliability (ASR, Segi-Doll world standard population: 6.4 cases per 100,000 habitants for 2008–2012). The incidence was also below the latest IARC predictions for Southern Europe (GLOBOCAN 2018). Histological characteristics of patients were similar to other Southern European series. Conclusions: The incidence of skin melanoma in Gran Canaria is unexpectedly low for a Southern European population exposed to such a high UVI. Further research in the Canary Islands could provide insight into a better understanding of melanoma pathogenesis.