[Clinical study of primary central nervous system lymphoma: the role of chemotherapy]

We conducted a retrospective study of 32 patients with histologically confirmed primary central nervous system lymphoma treated in our institute between 1971 and 1995 with an emphasis on the role of chemotherapy. Thirty of the 32 patients underwent tumor resection, whereas 2 patients had biopsies only. Twenty-eight patients received adjuvant therapy, 9 of whom received radiation therapy alone, 2 received chemotherapy alone, and 17 received both radiation therapy and chemotherapy. Chemotherapies performed were CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone). VEMP or VENP (vincristine, cyclophosphamide, mercaptopurine [or Natulan], and prednisolone), intravenous ACNU (nimustine), and intravenous or intra-arterial MCNU (ranimustine) and CBDCA (carboplatin). Survival data were available for 30 of the 32 patients. The median survival time of this study was 12.5 months. Twenty-seven patients died from one month through 79 months after the initiation of therapy, and 3 patients were alive for 13 to 69 months. Two patients who received the combination of radiation therapy and chemotherapy survived longer than 5 years. Although radiation therapy and chemotherapy were individually both effective and prolonged the survival time, their combination was more effective. The median survival time was significantly shorter (7.0 vs 16.5 months, p < 0.05) for the patients who received radiation therapy alone than for the patients who received the combination of radiation therapy and chemotherapy. We conclude from our results and review of previous studies that it is important for the chemotherapy of primary central nervous system lymphoma 1) to apply a combination of a variety of effective drugs, similar to that for systemic malignant lymphoma, and 2) to make a sufficient amount of anti-cancer drugs penetrate the whole central nervous system, thereby satisfying the adequate dose intensity for each drug.