Lymphoma Relapse Risk Lower with Autologous HSCT Than Radiotherapy

Patients with newly diagnosed primary central nervous system (CNS) lymphoma who received high-dose chemotherapy and autologous hematopoietic stem cell transplantation (AHSCT) had a lower risk of relapse than patients who received whole-brain radiotherapy (WBRT), according to long-term data from a clinical trial.

The results of the randomized, phase II PRECIS study were previously reported with an initial median follow-up of 33 months. The long-term data, with a median follow-up of eight years, were reported by Caroline Houillier, MD, of La Pitie Salpetriere Hospital, and colleagues in the Journal of Clinical Oncology.

Induction chemotherapy was followed by WBRT (n=53) or high-dose chemotherapy was followed by AHSCT (n=44). All patients were aged 18 to 60 years.

The eight-year event-free survival rate was significantly greater for patients treated with AHSCT (67%) compared to patients treated with WBRT (39%; P=.03). Eight-year overall survival was not significantly different between the AHSCT (69%) and WBRT arms (65%). However, the risk of relapse was significantly lower in the AHSCT arm (hazard ratio, 0.13; P<.001).

Balance and cognition declined in a significantly greater proportion of patients in the WBRT arm (52% and 64%, respectively; P<.001) than in the AHSCT arm (10% and 10%, respectively; P<.001).

A third of patients who relapsed after WBRT were alive after salvage treatment, while four patients died of WBRT-related toxicities and five patients died of AHSCT-related toxicities.

“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 AHSCT appears to be highly efficient in preventing relapses,” the authors concluded.

Houillier C, Dureau S, Taillandier L, et al. 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. J Clin Oncol. 2022. doi:10.1200/JCO.22.00491