Primary central nervous system lymphoma: From clinical presentation to diagnosis

Immunocompetent patients with primary central nervous system lymphoma (PCNS L) present with a median age of 55 years, immunosuppressed patients with a median age of 40 years. They show a broad range of signs and symptoms. Symp toms of increased intracranial pressure and personality change are most fre quent, followed in frequency by ataxia and hemiparesis. The median time fro m onset of symptoms to diagnosis is 3-5 months in immunocompetent patients and 2 months in immunodeficient patients. The time to diagnosis can be cons iderably longer in patients with slowly developing personality change or fl uctuating symptoms due to spontaneous or steroid-induced remission of so-ca lled sentinel lesions. Native CT scans show iso- or hyperdense lesions with homogenous contrast enhancement. T1-weighted MRI scans show hypointense an d T2-weighted scans hyperintense lesions. The definitive diagnosis of PCNSL requires biopsy. In some cases, however, the definitive diagnosis may excl usively be made by the demonstration of malignant B-lymphocytes in the cere brospinal fluid.