Hepatocellular Carcinoma in Sub-Saharan Africa

Abstract

More than 80% of global hepatocellular carcinoma (HCC) patients are estimated to occur in sub-Saharan Africa (SSA) and Eastern Asia. The most common risk factor of HCC in SSA is chronic hepatitis B virus (HBV) infection, with the incidence highest in West Africa. HBV is highly endemic in SSA and is perpetuated by incomplete adherence to birth dose immunization, lack of longitudinal follow-up care, and impaired access to antiviral therapy. HBV may directly cause HCC through somatic genetic alterations or indirectly through altered liver function and liver cirrhosis. Other risk factors of HCC in SSA include aflatoxins and, to a lesser extent, African iron overload. HIV plus HBV co-infection increases the risk of developing HCC and is increasingly becoming more common because of improving the survival of patients with HIV infection. Compared with the rest of the world, patients with HCC in SSA have the lowest survival. This is partly due to the late presentation of HCC with advanced symptomatic disease as a result of underdeveloped surveillance practices. Moreover, access to care and resource limitations further limit outcomes for the patients who receive a diagnosis in SSA. There is a need for multipronged strategies to decrease the incidence of HCC and improve its outcomes in SSA.

FIG 1

Age-standardized incidence and mortality rates of liver cancer in African countries across different regions of sub-Saharan Africa. (A) Eastern Africa, (B) Southern Africa, (C) Central Africa, and (D) Western Africa. ASR, age-standardized rates (incidence and mortality). Reproduced from GLOBOCAN 2018.

FIG 2

World map depicting the country-wise prevalence of chronic hepatitis B infection. Materials developed by CDC. Reproduced from Schweitzer et al.

FIG 3

Survival curves of hepatocellular carcinoma in different countries or continents. Reproduced with permission from Yang et al.