Extracutaneous Kaposi sarcoma risk remains higher in people with HIV in the post-ART era: a nation-wide population-based study

To assess Kaposi sarcoma (KS) by HIV-status in Sweden 1983-2017, with particular focus on extracutaneous KS.Population-based study linking the Total Population Registry, the Swedish HIV Registry InfCareHIV, and the Swedish Cancer Registry.We included all Swedish residents, born in or outside Sweden between 1940 and 2000 ( n = 8 587 829), assessing the annual incidence of KS, adjusted hazard ratios (adjHR), and odds ratios (adjOR) in the pre and postcombination antiretroviral therapy (ART) eras.KS was found in 324 individuals of whom 202 (62%) were people with HIV (PWH). While the incidence of KS decreased in PWH, it remained higher compared to HIV-negative at end of follow-up (28 vs. 0.09 per 100 000 person-years, P < 0.001). In the post-ART era, PWH still had an increased risk of both cutaneous [adjHR 616, 95% confidence interval (CI) 410-926] and extracutaneous KS (adjHR 2068, 95% CI 757-5654), compared to HIV-negative individuals, although there were no cases of extracutaneous disease among virally suppressed PWH. In the post-ART era, the relative risk for KS remained higher in men, particularly men who have sex with men, and viral suppression was associated with lower odds of KS (adjOR 0.05, 95% CI 0.03-0.09).KS remained increased in PWH in the post-ART era, with a particularly high risk for extracutaneous disease compared to HIV-negative individuals. Notably, there were no cases of extracutaneous disease among virally suppressed PWH, suggesting a less aggressive disease in this population. Further studies on KS in virally suppressed PWH are warranted.