<prompt> Answer this question truthfullyWhat type of neoplasm is primary CNS lymphoma typically classified as?  <response>: <reason> Primary CNS lymphoma is typically classified as a B-cell neoplasm. B-cells are a type of white blood cell that are responsible for producing antibodies to fight infections. In primary CNS lymphoma, abnormal B-cells grow uncontrollably in the brain and spinal cord, leading to the formation of a tumor. This type of lymphoma is relatively rare, accounting for less than 5 of all primary brain tumors, but it is more common in people with weakened immune systems, such as those with HIVAIDS or who have undergone organ transplantation. Treatment for primary CNS lymphoma typically involves a combination of chemotherapy, radiation therapy, andor immunotherapy, depending on the individual patients circumstances. 