Primary central nervous system lymphoma: a clinicopathological study of 28 cases.

A group of 28 consecutive patients (mean age 59 years) with primary central nervous system lymphoma (PCNSL) was treated with different regimens, including steroids only, radiotherapy (RT), chemotherapy or combinations of all. Lymphoma was classified as high grade malignant B-cell non-Hodgkin's lymphoma of the diffuse large cell type in each of these cases. RT alone led to tumour remission in more than 70 per cent, survival could be prolonged with additional chemotherapy. Thirteen patients were treated with chemotherapy alone; nine of them received a novel combined intraventricular and systemic polychemotherapy protocol based on high dose methotrexate (MTX) and high dose cytarabine (ara-C). The response rate was 90 per cent with 80 per cent complete responses. Neurotoxicity, i.e. white matter lesions associated with severe cognitive dysfunction affected both patients surviving RT more than a year and patients treated with combination RT/chemotherapy. Confluent white matter hyperintense lesions were detectable on MRI in three out of 13 patients treated with chemotherapy alone, however, cognitive dysfunction has not been detected in these patients.