Global trends in Kaposi sarcoma incidence and mortality: the need for action to reduce inequalities.

Kaposi sarcoma is a malignant vascular neoplasia that develops into skin lesions, it can involve one or multiple internal organs, and it is classified as an AIDS-defining cancer. Four clinical–epidemiological forms are recognised: classic, endemic, transplant-associated, and epidemic (AIDS-associated).1Antman K Chang Y Kaposi's sarcoma.N Engl J Med. 2000; 342: 1027-1038Crossref PubMed Scopus (818) Google Scholar The frequency of Kaposi sarcoma varies across different populations and countries. In The Lancet Global Health, Leiwen Fu and colleagues2Fu L Tian T Wang B et al.Global patterns and trends in Kaposi sarcoma incidence: a population-based study.Lancet Glob Health. 2023; 11: e1566-e1575Google Scholar describe the geographical distribution of Kaposi sarcoma incidence and mortality and trends in incidence rates. Using secondary data, both from GLOBOCAN 2020 and Cancer Incidence in Five continents (CI5), the study depicts the disproportionate burden of Kaposi sarcoma incidence and mortality among African countries, which naturally reflects the high levels of exposure to Kaposi sarcoma-associated herpesvirus (KSHV; the causal agent of Kaposi sarcoma) and HIV, but also suboptimal access to antiretroviral therapy in the region. These, however, are not the only inequalities highlighted in this study. Despite Kaposi sarcoma being estimated to be a common cancer in some African countries,3Meireles P Albuquerque G Vieira M et al.Kaposi sarcoma incidence in Mozambique: national and regional estimates.Eur J Cancer Prev. 2015; 24: 529-534Crossref Scopus (6) Google Scholar empirical data supporting these claims are scarce;4Carrilho C Fontes F Tulsidás S et al.Cancer incidence in Mozambique in 2015-2016: data from the Maputo Central Hospital Cancer Registry.Eur J Cancer Prev. 2019; 28: 373-376Crossref PubMed Scopus (0) Google Scholar GLOBOCAN 2020 provides estimates for all countries, based on the best available data, but in Africa these figures are largely based on regional data or observations from neighbouring countries, because population-based cancer registries are often absent or have limited regional coverage, and mortality statistics are not widely available in the region.5WHOIARCCancer today data & methods.https://gco.iarc.fr/today/data-sources-methodsDate accessed: August 12, 2023Google Scholar When CI5 data from high quality population-based cancer registries was used to evaluate time trends in cancer incidence, these gaps became even more evident, because only Uganda was represented. This fact is not surprising, because cancer registration is resource-consuming, which limits its proper implementation in low Human Development Index (HDI) countries. Although some initiatives are being carried out to improve data in these settings, particularly in sub-Saharan Africa,6Omonisi AE Liu B Parkin DM Population-based cancer registration in sub-Saharan Africa: its role in research and cancer control.JCO Glob Oncol. 2020; 6: 1721-1728Crossref PubMed Scopus (18) Google Scholar adequate funding and local-specific strategies to overcome the difficulties posed by weak health systems are still needed for continued and fruitful cancer surveillance efforts. The study by Fu and colleagues also shows differences in the trends in Kaposi sarcoma incidence between countries. Declines were observed not only in Europe, Latin America, the USA, but also in many regions of sub-Saharan Africa, probably reflecting a combination of factors, with varying importance across countries and periods, such as the introduction of antiretroviral therapy, preventive HIV actions with consequent decrease of incidence and prevalence of HIV (safe sexual practices and male circumcision), and a decrease of KSHV prevalence. The increasing trends in incidence in the Netherlands and Türkiye described by Fu and colleagues show the need for continuous reinforcement of HIV preventive actions in populations at high risk of HIV. In summary, the results from this study show the uneven distribution of Kaposi sarcoma and heterogeneous cancer incidence and mortality data across countries, showing the need for action, namely the widespread provision of appropriate care to patients who are infected with HIV infected and patients with Kaposi sarcoma. Also, improvements in cancer surveillance are needed for enhancing the understanding of cancer epidemiology in low HDI settings, as well as to support prevention and control efforts. We declare no competing interests. Global patterns and trends in Kaposi sarcoma incidence: a population-based studyKaposi sarcoma is a relatively rare cancer worldwide but is endemic in some countries in southern and eastern Africa. Addressing disparities in health-care resource allocation and improving HIV/AIDS care across different HDI regions might contribute to the prevention of Kaposi sarcoma. Full-Text PDF Open Access