Non-AIDS primary CNS lymphoma: first example of a durable response in a primary brain tumor using enhanced chemotherapy delivery without cognitive loss and without radiotherapy.

PURPOSE: Radiographic tumor response and survival were evaluated in patients receiving methotrexate-based chemotherapy with osmotic blood-brain barrier disruption with or without antecedent cranial radiation. PATIENTS AND METHODS: Fifty-eight non-AIDS patients (38 males, 20 females) with histologically confirmed primary central nervous system lymphoma, primarily large cell or immunoblastic, were treated at the Oregon Health Sciences University from January 1982 through March 1992. Group 1 patients (n=19) received cranial radiation prior to referral; Group 2 (n=39) received initial blood-brain barrier disruption chemotherapy. Ages ranged from 5 to 71 years (median, 57); Karnofsky performance status was 40% to 100% on inclusion (median, 80) and all underwent extensive baseline neuropsychological evaluation.
RESULTS: There was no significant difference in patient characteristics between the two groups. In 15 evaluable Group I patients, 14 demonstrated objective response and 7 of 14 (50%) achieved complete response. In Group 2, 34 of 35 evaluable patients demonstrated objective response, including 29 of 34 with complete response. Estimated median survival times for Group 1 and Group 2 patients were 16 and 41 months, respectively. Currently, 19 Group 2 patients and 2 Group 1 patients are alive. Extensive neuropsychological follow-up (up to 7 years from baseline) was completed in 23 patients, which demonstrated preservation or improved cognitive function in those receiving initial chemotherapy and blood-brain barrier disruption, most notably in patients older than 60 years.
CONCLUSIONS: A plateau in survival curves suggests that a portion of primary central nervous system lymphoma patients may be cured with chemotherapy and blood-brain barrier disruption without the neurologic sequelae associated with cranial radiation.