Abstract
The benefits of radio-chemotherapy in HIV-negative primary central nervous
system (CNS) lymphomas were analyzed in 40 patients, who received radiotherapy
to the brain or craniospinal axis with the total dose of 4460-5940 cGy to the
primary tumor. Radiotherapy was followed by systemic chemotherapy, mainly with
the cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP) regimen,
in 16 of the patients. Follow-up ranged from four to 95 months with a median of
15 months. The relapse rate was 72.5%, and 83% of the relapses occurred within
the radiation field. Median survival was 19 months and the two-year survival
rate was 41%. Survival was significantly influenced by treatment method and
radiation dose when measured by univariate analysis; median survival and the
two-year survival rate was 29 months and 63% after radio-chemotherapy, while
13.5 month and 29% after radiotherapy alone (p=0.027), and 22 months and 49%
with doses of 50 Gy or more, but 12.5 months and 13% with doses less than 50 Gy
(p=0.009). However, statistical significance was lost in multivariate analysis.
These results might suggest the short-term efficacy of radio-chemotherapy,
however, cautious observation is needed to confirm long-term effects.