Which virus is strongly associated with primary CNS lymphoma?

Primary CNS lymphoma is a type of brain tumor that is notably associated with immunosuppression, particularly in patients with HIV/AIDS. However, the strongest association for primary CNS lymphoma is with Epstein-Barr virus (EBV). This virus can lead to lymphoproliferative diseases in individuals with weakened immune systems. In immunocompromised patients, such as those with HIV, EBV can cause aggressive lymphoid proliferation, contributing to the development of primary CNS lymphoma.

EBV acts as a latent infection in lymphocytes and is known to drive the oncogenic process in lymphomas. The presence of EBV in the tumor cells of primary CNS lymphoma is a hallmark of this association. Although HIV is prevalent in patients who develop primary CNS lymphoma, the direct link to the lymphoma itself is more specifically attributed to EBV.

The other viruses mentioned do not have a strong or direct association with primary CNS lymphoma. Influenza virus primarily affects the respiratory system and does not have a role in lymphomagenesis. Cytomegalovirus (CMV) can cause opportunistic infections in immunocompromised patients, but it is not directly linked to the development of CNS lymphomas.