Stereotactic radiosurgery in the treatment of primary central nervous system lymphoma.

Objective: To explore the therapeutic alternatives and evaluate the related clinical results of patients with primary central nervous system lymphoma (PCNSL) treated with gamma knife radiosurgery (GKS).

Methods: From January 1995 to December 2001, 44 patients suffering from PCNSL, who had undergone stereotactic biopsy or craniotomy, and who had received a confirmed diagnosis through pathological examination, were treated with GKS. All cases were followed up for 1 - 46 months with an average postoperative period of 27 months. The clinical materials, image features, treatment methods and results of follow-up, were retrospectively reviewed.

Results: The symptoms and signs of the patients were markedly improved within 1 - 3 weeks after GKS. The Kanofsky performance status was also improved from a preoperative average of 40% to a postoperative one of 90%. Thirty-eight patients (86.36%) were in complete remission (CR), the other six (13.63%) were in partial remission (PR). The local control rate reached 100%, and the median survival time was 26.5 months. The main side effect was brain edema, which can be treated with dexamethasone and mannitol.

Conclusions: GKS is a safe and effective method in multimodality treatment of PCNSL. A stereotactic biopsy coupled with GKS is the first choice for diagnosis and treatment. Adjuvant chemotherapy or radiotherapy should then be given according to the patient's condition.