Primary effusion lymphoma involving the cerebrospinal fluid.

Primary effusion lymphoma or body cavity based lymphoma is a form of large B-cell lymphoma which usually presents as serous effusions without detectable tumor masses. It is universally associated with human herpesvirus-8 also known as Kaposi sarcoma herpesvirus. This condition, so far, has been reported in the body cavity effusions that include pleura, peritoneum, and pericardium. We report a case of primary effusion lymphoma which has involved the cerebrospinal fluid. To our knowledge, this is the first case of PEL reported in the cerebrospinal fluid.