Positron emission tomography derived metrics in relapsed or refractory large B‐cell lymphoma with residual disease before autologous stem cell transplant

Abstract

Summary Salvage chemotherapy followed by high‐dose chemotherapy and autologous stem cell transplantation (ASCT) is a potentially curative treatment for patients with relapsed or refractory large B‐cell lymphoma (rrLBCL) with chemosensitive disease. A18F‐fluorodeoxyglucose positron emission tomography (PET) scan after salvage chemotherapy is used to assess response and eligibility for ASCT, but metrics for chemosensitivity in patients with residual disease are not well defined. We performed a single‐centre retrospective analysis of 92 patients with a partial response or stable disease after salvage chemotherapy for rrLBCL who received ASCT to investigate PET‐derived parameters and their prognostic utility. The Deauville 5‐point Scale (D‐5PS) score, maximum standardised uptake value (SUVmax), total metabolic tumour volume (TMTV), and total lesion glycolysis (TLG) were calculated from the post‐salvage/pre‐ASCT PET scan. The 5‐year progression‐free survival (PFS) and overall survival (OS) rates were 40% and 54% respectively. A D‐5PS score of 5 (p = 0.0082, hazard ratio [HR] 2.09), high SUVmax (p = 0.0015, HR 2.48), TMTV (p = 0.035, HR 1.83) and TLG (p = 0.0036, HR 2.27) were associated with inferior PFS. A D‐5PS score of 5 (p = 0.030, HR 1.98) and high SUVmax (p = 0.0025, HR 2.55) were associated with inferior OS. PET‐derived parameters may help prognosticate outcomes after ASCT in patients with rrLBCL with residual disease after salvage chemotherapy.

Are dynamic or fixed FDG‐PET measures of disease of greater prognostic value in patients with relapsed/refractory diffuse large B‐cell lymphoma undergoing autologous haematopoietic stem cell transplantation?

“…Approximately 50% of patients planned for ASCT fail to achieve CMR after salvage immunochemotherapy, 26 and for these patients, the optimal course of therapy is less clear. Yet, of this group with less than CMR who do proceed to ASCT, approximately half will remain alive and relapse free at 3 years, 10,25 suggesting that the Deauville score alone is insufficient to identify patients most likely to benefit from ASCT 27 . Therefore, an improved predictive method beyond the Deauville score is required to identify patients most likely to benefit from ASCT, and, conversely, to identify those who can be spared the morbidity of ASCT by re‐direction to other alternative treatment pathways, such as CAR‐T cell therapy.…”

The role of additional chemotherapy prior to autologous HCT in patients with relapse/refractory DLBCL in partial remission—A retrospective multicenter study

“…The implication of these findings is that functional imaging may serve as a prognostic tool to guide treatment decision‐making and identify a high‐risk subset of patients with inferior outcomes after HCT. These patients may benefit from nonchemotherapy‐based strategies such as CAR‐T and novel monoclonal antibodies 21 …”

“…These patients may benefit from nonchemotherapy-based strategies such as CAR-T and novel monoclonal antibodies. 21 Several limitations must be considered in the interpretation of our results. First, the retrospective design is subject to inherent selection bias of nonrandomized retrospective data, which may possibly explain the considerable superior outcomes of the cohort referred directly to HCT.…”

“…These patients may benefit from nonchemotherapy‐based strategies such as CAR‐T and novel monoclonal antibodies. 21 …”

Do we have to exclude all relapsed diffuse large B‐cell lymphoma patients not in complete remission from autologous stem cell transplant?

“…In their paper, Cherng and colleagues 1 discuss the eligibility of patients not in CR after salvage therapy for standard ASCT. These patients include partial responders (PRs) or those with stable disease (SD) who are still PET‐scan‐positive with a Deauville (DS) five‐point score (5PS) of 4 or 5.…”