Kaposi sarcoma incidence and mortality trends and disparities in the United States

Kaposi sarcoma (KS) is an angioproliferative tumor caused by human herpesvirus 8 and is an AIDS-defining illness. Combination antiretroviral therapy (ART) was introduced in the United States in 1996, after which U.S. KS incidence declined and survival improved; however, persistent racial and sex disparities remain. Our aim was to characterize 1999-2020 trends in KS incidence and mortality in the United States overall, and by race and sex, and to quantify changes in disparities over time.

We extracted KS case and death counts from the CDC WONDER database (ICD-10 codes B21.0, C46). Age-adjusted incidence rates (AAIR) and mortality rates (AAMR) per 100,000 were calculated by year, race, and sex. Temporal trends were evaluated using the Mann-Kendall test (Kendall's τ), and between-group differences by t-test (α = 0.05).

From 1999 to 2020, 27,886 KS cases and 4,380 deaths occurred. Overall AAIR was 0.99 in men versus 0.10 in women, and AAMR 0.16 versus 0.01 (both p < 0.001). Black men experienced the highest AAIR (2.23) and AAMR (0.40), significantly exceeding White men (0.79 and 0.13; p < 0.001). Incidence declined in both sexes (men: -46.7%, τ = -0.920; women: -58.9%, τ = -0.848; both p < 0.001). Mortality declined in men (-66.4%, τ = -0.581; p < 0.001). Among women, AAMR levels were very low throughout (mean ≈ 0.01 per 100,000); the end-to-end change from 1999 to 2020 was + 28.6%, yet the Mann-Kendall test did not identify a monotonic trend (τ = - 0.303; p = 0.060), reflecting early declines followed by year-to-year fluctuation around a low baseline.

Although KS incidence and mortality have declined markedly since 1999, Black men remain disproportionately affected. Focused public health efforts and enhanced access to HIV care are essential to close these gaps.

Not applicable.