Primary CNS lymphoma (PCNSL) is a type of cancer that starts in the lymphocytes, a type of white blood cells, in the central nervous system (CNS). It is called "primary" because it originates in the brain or spinal cord, rather than spreading to the CNS from another part of the body.
PCNSL most commonly affects people with weakened immune systems, such as those with HIV/AIDS or individuals who have undergone organ transplantation and are on immunosuppressive medications.
