Racial disparities in incidence & survival of Kaposi's sarcoma in the United States

Abstract

Background & objectives: In the United States (US), Kaposi's sarcoma (KS) is usually seen in the patients affected by human immunodeficiency virus (HIV). The racial differences in the incidence rates and survival of patients with KS have been reported in the US. We undertook this study to analyse the disparities in the race-specific incidence rate and survival of KS patients of two different races in the US based on SEER (Surveillance, Epidemiology and End Results) database. Methods: Data on KS patients of African-American (AA) and non-Hispanic White (NHW) races who were diagnosed during 1973-2013 were extracted from SEER database to estimate the incidence rates and survival of KS patients. Results: A total of 18,388 NHWs and 3,455 AAs were diagnosed with KS. The age-adjusted incidence rate (AAIR) of KS in patients aged 20-44 yr was 3.8 times higher in AAs than in NHWs. The decline in AAIR of KS among NHWs started during 1989-1994 and preceded decline in the AAIR of AAs. After introduction of highly active antiretroviral therapy (HAART), the incidence continued to decline, but the decrease in the AAIR in AAs [annual percentage change (APC): −6.2; 95% confidence interval (CI): −8.8 to −3.5] was slower than that in NHWs (APC: −10.9; 95% CI: −12.6 to −9.1). The hazard ratio for all-cause mortality in KS patients of the AA race increased from 1.1 (95% CI: 1-1.2) in 1981-1995 to 1.55 (95% CI: 1.4-1.7) in 1996-2013 as compared to those of the NHW race. Interpretation & conclusions: Several significant racial disparities that emerged after HAART introduction in the incidence and survival of KS patients continued to persist, despite improvement in care of patients with HIV. Further studies need to be done to find out the underlying factors leading to these disparities.

Epidemiology and Survival of Kaposi’s Sarcoma by Race in the United States: A Surveillance, Epidemiology, and End Results Database Analysis

“… 2 Kumar et al demonstrated that this trend continued for KS patients diagnosed up until 2013. 3 KS incidence continued to decline, but the decrease in the age-adjusted incidence rate (AAIR) in Black patients [annual percentage change (APC): −6.2; 95% CI: −8.8 to −3.5] was slower than that in White patients (APC: −10.9; 95% CI: −12.6 to −9.1). The hazard ratio for all-cause mortality in Black KS patients increased from 1.1 (95% CI: 1–1.2) in 1981–1995 to 1.55 (95% CI: 1.4–1.7) in 1996–2013 as compared to White patients.…”

“…The hazard ratio for all-cause mortality in Black KS patients increased from 1.1 (95% CI: 1–1.2) in 1981–1995 to 1.55 (95% CI: 1.4–1.7) in 1996–2013 as compared to White patients. 3 These racial disparities in KS incidence and outcomes may be explained by adherence to HAART treatment. HAART treatment compliance and successful HAART treatment is less likely in African American patients as compared to in non-Hispanic White patients which may result in higher rates of HIV and HHV-8 co-infection.…”

“…1 In recent years, the introduction of highly active antiretroviral treatment (HAART) has led to a significant decrease to about 6 cases per million people. [1][2][3] However, substantial racial disparity has been reported in the incidence and survival of KS patients in the HAART era. [2][3][4] Here, we analyze data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEERs) Program for epidemiology and survival of Kaposi's sarcoma by race.…”

Understanding racial diversities in Kaposi's sarcoma

“…In an analysis of population-based cancer incidence and survival spanning over four decades in this issue, Kumar et al 8 present trend data on racial differences in incidence of KS and survival in the United States of America highlighting the changes observed after the introduction and increasing availability of HAART. The analysis showed higher and continued incidence of KS in certain regions of USA particularly among African-Americans (AA).…”

“…A significant limitation of the study by Kumar et al 8 was that the Surveillance, Epidemiology and End Results (SEER) database covered only a proportion of the AA and NHW populations. Hence, if there are differences between the data in SEER database and the actual real life data on KS in the health systems, estimates of incidence and survival among AA as well as NHW would have some bias.…”