Prognostic Value of PET Status for Patients With R/R Follicular Lymphoma Undergoing AutoSCT

Prognostic Value of PET Status for R/R Follicular Lymphoma AutoSCT 

Pre-autologous stem cell transplantation (autoSCT) positron emission tomography (PET) status has strong prognostic value and may help to improve the risk stratification and selection of patients with relapsed/refractory (R/R) follicular lymphoma (FL) for autoSCT, according to a multicenter retrospective analysis published in Haematologica.

According to Toby A. Eyre, MD, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom, and coauthors, “the optimum management approach for patients with relapsed or refractory follicular lymphoma remains uncertain,” posing significant challenges in treatment. Although autoSCT is a standard option of treatment, especially for suitable younger patients with FL, it is associated with notable toxicities. Moreover, while there is evidence that positron emission tomography (PET) status is a valuable prognostic factor in other lymphomas, its significance in FL has yet to be established. 

This analysis aimed to investigate the impact of pre-transplant PET status on survival outcomes among patients with R/R FL who underwent autoSCT. The primary endpoint was PFS stratified according to PET-based response before autoSCT, and the secondary endpoints included overall survival, non-relapse mortality, cumulative incidence of relapse, engraftment, and change in the depth of PET status after autoSCT. 

This retrospective analysis included 172 patients with R/R FL who had undergone autoSCT and received a median of 3 lines of therapy prior to transplantation. These patients were from a national, multicenter registry study conducted by the British Society of Blood and Marrow Transplantation and Cellular Therapy. The survival outcomes were assessed according to pre-transplant PET status, classified into complete metabolic remission (CMR) and non-CMR, according to the Lugano criteria.

At a median follow-up of 27 months, the median PFS for all patients was 28 months. Notably, the study authors found no correlation between age at transplantation, sex, number of months since last relapse, Karnofsky performance status or comorbidity index and achieving CMR prior to autoSCT. Superior PFS was noted in 67% of patients (n = 115) who achieved CMR. Meanwhile, 33% (n = 57) were classified as non-CMR (3-year PFS 50% vs. 22%, P= 0.011). Superior progression-free survival was observed in 115 (67%) patients obtaining CMR versus 57 (33%) non-CMR patients (3-year progression-free survival 50% vs. 22%, P = 0.011) and by a pre-SCT 5-point Deauville score (hazard ratio [HR], 1.32; P = 0.049). 

Overall, study authors found that PET status was independently associated with progression-free status (non-CMR HR, 2.02; P = 0.003), overall survival (non-CMR HR, 3.08; P = 0.010) and risk of relapse (non-CMR HR, 1.64, P = 0.046) after autoSCT by this multivariable analysis. 

“Our data suggest that pre-SCT PET status is of clear prognostic value and may help to improve the selection of patients for autoSCT,” the study authors concluded. 

Source: 

Eyre T A, Barrington S F, Okosun J, et al. Impact of positron emission tomography-computed tomography status on progression-free survival for relapsed follicular lymphoma patients undergoing autologous stem cell transplantation. Haematologica. 2023;108(3):785-796; doi:10.3324/haematol.2021.280287