EBV is a human herpesvirus that preferentially infects B lymphocytes. It can either:
- Express a small volume of its genome, causing cell survival and proliferation, or
- Express the entire genome, generate new virions, and lyse the cell to release the new infective cells
The ability of EBV to promote cell survival and proliferation causes it to be an oncogenic virus. It is associated with:
- 100% of cases of Burkitt lymphoma
- It is hypothesised that in Africa where Burkitt lymphoma is most common, co-infection with malaria dampens the T-cell response against EBV infection, allowing increased proliferation of infected B cells and increased likelihood of the characteristic translocation involving c-MYC.
- 100% of cases of post haematological transplant lymphoma and many post-solid organ transplant lymphoma
- 100% of endemic cases of nasopharyngeal carcinoma
- Endemic cases harbour the EBV genome, although it is thought not be to be the initiating step in carcinogenesis
- A significant percentage of Hodgkin's lymphoma
- About 10% of stomach malignancies
The role of EBV in those malignancies where all cases do not harbour EBV is less certain.