Purpose: We consider that whatever the vital prognosis of secondary CNS lymphoma (SCNSL), its local control is as serious as that of primary CNS lymphoma (PCNSL). In this study, both the treatment outcomes and local control of patients with SCNSL and PCNSL were compared, with the aim of improving the treatment of SCNSL.
Materials and methods: This study included 11 patients with PCNSL and 14 with SCNSL treated from January 1984 to October 1997. PCNSL patients underwent partial tumor resection and received systemic chemotherapy. All SCNSL patients received systemic chemotherapy, and eight also received intrathecal anticancer drug infusion. Nine PCNSL patients and 11 SCNSL patients underwent whole-brain radiation therapy with 4-MV photons. Among the SCNSL patients, three patients underwent localized-brain irradiation and two patients also received whole-spine irradiation.
Results: Five-year survival rates were 34% for PCNSL and 33% for SCNSL. In SCNSL, survival times after CNS involvement were very short, irrespective of treatment. One-year local control rates after CNS irradiation were 38% for PCNSL and 14% for SCNSL. Recurrence was mainly found in the cranial region, in seven of 11 PCNSL patients and 10 of 14 SCNSL patients.
Conclusions: Patients with SCNSL had a poor prognosis, and local control in them was more problematic than in patients with PCNSL. It is necessary to develop new combined modality therapy for patients with SCNSL,including the participation of a radiation oncologist, before the disease becomes progressive.