Non-Hodgkin Lymphomas in West Africa: Risk Factors and Survival

Non-Hodgkin lymphomas (NHL) are one of the most common malignant tumors in West Africa. Although the etiological factors of NHL remain largely unknown, several infectious agents, such as HIV infection, have been associated with these cancers. There is growing evidence that infection with the hepatitis B virus (HBV) may be linked to NHL, but the number of well-conducted epidemiological studies remains limited, particularly in areas with high HBV endemicity such as sub-Saharan Africa. In many cases, NHLs can be effectively treated with standard chemotherapy regimens. However, little is known about actual access to these treatments in West Africa and their impact on remission and survival, particularly in the context of HIV infection.ObjectivesOur primary objective is to assess the association between HBV and NHL in West Africa. The secondary objectives are (I) to characterize access to chemotherapy for NHL in various care settings and according to HIV infection status, (II) to assess follow-up and survival among patients diagnosed with NHL and to explore their determinants, (III) to assess the extent of potential reactivation of latent HBV infection in NHL cases with access to chemotherapy.Methods: A case-control study will be conducted at referral hospitals in Abidjan (Ivory Coast) and Dakar (Senegal). The departments responsible for hematopoietic malignancies at each referral hospital will be asked to participate in the recruitment of at least 120 cases of NHL. All cases will undergo histological confirmation with double reading—first locally and then centrally in Bordeaux—combined with routine immunohistochemical testing. A control group of patients not suspected of having hematopoietic malignancies will be established, matched to the cases by age (± 2 years), sex, and referral center. All cases and controls will then be screened for all HBV markers as well as other infectious agents, notably HIV and HCV. A cohort study will then be conducted, including diagnosed cases of NHL who received treatment. These treated NHL cases will be followed for a period of 24 months.ExpectedResults The burden of HBV infection is particularly high in West Africa, with estimates of the prevalence of chronic HBsAg carriage ranging from 8% to 15% in the adult population. A better understanding of the potential link between HBV and NHL in West Africa will have major implications, as this infection is amenable to prevention strategies. Our approach will also help describe access to care for NHL in various settings across West Africa and identify gaps between needs and actual access to treatment.