What is the most common CNS cancer in patients with AIDS?

Primary CNS lymphoma is the most common central nervous system cancer found in patients with AIDS. This type of lymphoma specifically arises from lymphoid tissue located in the brain and is closely associated with the immunocompromised state of individuals with HIV/AIDS. The increased risk for this malignancy in such patients is largely due to the virus’s effect on the immune system, leading to a decreased ability to combat certain infections and malignancies, particularly those caused by opportunistic pathogens.

Patients with AIDS often experience neurological symptoms related to CNS lymphoma, including changes in mental status, seizures, and focal neurological deficits. The diagnosis is typically confirmed through neuroimaging techniques, such as MRI, which can reveal mass lesions, and through biopsy, which provides histological evidence of lymphocytic infiltration.

Among the other options, glioblastoma multiforme, meningioma, and high-grade brain-stem glioma are less commonly associated with AIDS. While any cancer can potentially occur in individuals with a compromised immune system, primary CNS lymphoma stands out as the most prevalent tumor in this specific population due to the direct impact of HIV on immune surveillance and lymphocyte function.