Radiotherapy or Autologous Stem-Cell Transplantation for Primary CNS Lymphoma in Patients Age 60 Years and Younger: Long-Term Results of the Randomized Phase II PRECIS Study

JCO We previously reported the results of a randomized phase II study in patients with newly diagnosed primary CNS lymphoma (age 18-60 years). Patients were treated with high-dose methotrexate-based induction chemotherapy followed by whole-brain radiotherapy (WBRT) or high-dose chemotherapy (thiotepa-busulfan-cyclophosphamide) with autologous stem-cell transplantation (ASCT). The median follow-up was 33 months. In this report, we provide long-term data (median follow-up, 8 years) regarding the outcomes and toxicities. Fifty-three and 44 patients received induction chemotherapy followed by WBRT or ASCT, respectively. Their 8-year event-free survival from random assignment was 67% and 39% in the ASCT and WBRT arms, respectively ( = .03), with a significantly lower risk of relapse after ASCT (hazard ratio, 0.13; < .001). One third of patients who relapsed after WBRT were alive after salvage treatment. Five and four patients died of ASCT and WBRT-related toxicities, respectively. The 8-year overall survival was 69% and 65% in the ASCT and WBRT arms, respectively (not significant). Balance (52% 10%, ≤ 0.001) and neurocognition (64% 13%, < .001) significantly deteriorated after WBRT compared with ASCT during the follow-up. This study shows that 40 Gy WBRT should be avoided in first-line treatment because of its neurotoxicity and suboptimal efficacy in reducing relapses while ASCT appears to be highly efficient in preventing relapses.