Low dose whole-brain radiotherapy on patients unresponsiveto high dose methotrexate chomotherapy in short term failure for primary central nervous system lymphoma

Objective To investigate the efficacy and safety of low dose whole-brain radiotherapy combined with residual disease intensity-modulated radiotherapy on PCNSL patients.Methods A total of 16 patients,who were unresponsive to high dose methotrexate in short term,were treated with low dose whole-brain radiotherapy (24 Gy) combined with intensity-modulated radiotherapy (16Gy).After radiotherapy,the follow-up data were collected.Results Grade Ⅰ-Ⅱ of acute treatment toxicity was found,toxicity of more than Ⅲ was not observed.In all 16 cases,there were 7 cases for CR,9 cases for PR,no cases for SD and PD.KPS were improved in 15 patients,and not change in 1 patient.And thereLMwas no reduction of cognitive ability in these patients.Progression free survival rates in 6,12,and 24 months were 37.5%,6.25% and 0.0%,respectively.The free survival time of median progression was 6.0 month.Overall survival rates in 6,12,and 24 months were 93.75%,43.75% and 12.5%,respectively.The survival time of total median was 13.0 month.Conclusion This study demonstrated that low dose whole-brain radiotherapy combined with residual disease intensity-modulated radiotherapy is effective and safe for PCNSL patients who were unreponsvie to high dose methotrexate in short-term.