Long-term survival in primary CNS lymphoma treated by high-dose methotrexate monochemotherapy: role of STAT6 activation as prognostic determinant

J Neurooncol. 2009 Mar;92(1):65-71. doi: 10.1007/s11060-008-9736-9. Epub 2008 Nov 22.


We report a single-center experience of 16 immunocompetent patients diagnosed with primary central nervous system lymphoma and treated with monochemotherapy with high-dose methotrexate (MTX) and deferred radiotherapy. MTX was given at a dose of 8.0 g/m2 for induction and at a dose of 3.5-8.0 g/m2 for maintenance. There were eight complete responses (CR), one partial response, one stable disease, and six patients whose tumors progressed in spite of the chemotherapy. At final follow-up, five of five CRs were alive and well without radiotherapy, with median follow-up of 26 months. Overall survival in eight non-CRs treated with the subsequent radiotherapy was 36 months. In the immunohistochemical study, STAT6 was positively expressed in 8 out of 13 cases. They included all non-CRs and two CRs. This observation suggests that STAT6 expression can be used as a prognostic determinant for MTX chemotherapy.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Antimetabolites, Antineoplastic / administration & dosage*
  • Biomarkers, Tumor / analysis
  • Central Nervous System Neoplasms / drug therapy
  • Central Nervous System Neoplasms / metabolism*
  • Central Nervous System Neoplasms / mortality
  • Disease-Free Survival
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • Immunohistochemistry
  • Kaplan-Meier Estimate
  • Lymphoma, Non-Hodgkin / drug therapy
  • Lymphoma, Non-Hodgkin / metabolism*
  • Lymphoma, Non-Hodgkin / mortality
  • Male
  • Methotrexate / administration & dosage*
  • Middle Aged
  • Prognosis
  • STAT6 Transcription Factor / metabolism*


  • Antimetabolites, Antineoplastic
  • Biomarkers, Tumor
  • STAT6 Transcription Factor
  • STAT6 protein, human
  • Methotrexate