Primary central nervous system lymphoma.

Primary central nervous system lymphoma is an aggressive lymphoma with a molecular biology and genetic profile that appears to be distinct from other types of diffuse large B-cell lymphoma. The median survival after whole brain radiotherapy alone is poor, but is significantly improved after high-dose methotrexate-based combination chemotherapy. The rarity of primary central nervous system lymphoma means that randomised studies have proved challenging, particularly as many patients are elderly and more susceptible to the toxic effects associated with these treatments. Promising treatment strategies are emerging and, wherever possible, patients should be treated within clinical trials. Quality of life and neurocognitive data should be collected prospectively to assess the effect of the disease and treatment.