Interim PET-driven strategy in de novo diffuse large B-cell lymphoma: do we trust the driver?

Abstract

18F-Fluorodeoxyglucose–positron emission tomography (FDG-PET) has become a central tool for both accurate initial staging and determination of prognosis after treatment of diffuse large B-cell lymphoma (DLBCL). However, the role of PET during treatment (iPET) in daily practice remains a matter of significant debate. This perspective reviews the published studies on iPET in DLBCL, including the methods used to analyze iPET, its timing, and studies of iPET-driven therapy to illuminate where daily practice may benefit from the use of iPET. When performed after 2 and/or 4 courses of immunochemotherapy, iPET has a very good negative predictive value, utilizing both visual (qualitative) and semiquantitative methods. The visual method accurately predicts outcome for patients with limited disease. The semiquantitative method, eg, the change of the difference of maximum standardized uptake value (ΔSUVmax), is for patients with advanced DLBCL, for whom iPET identifies patients with very good outcome with continuation of standard therapy. A low ΔSUVmax also helps identify patients with a risk for relapse averaging 50% and warrants review of their scheduled therapy. To date, no trial has demonstrated the superiority of an iPET-driven strategy in DLBCL. However, the very good negative and good positive predictive values of iPET support its use in daily practice as a better predictive tool than contrast-enhanced computed tomographic scan for therapeutic decision making.

A better prediction of progression‐free survival in diffuse large B‐cell lymphoma by a prognostic model consisting of baseline TLG and %ΔSUVmax

“…Diffuse large B‐cell lymphoma (DLBCL) is the most prevalent type of non‐Hodgkin lymphoma. Although the addition of rituximab to a CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)‐like regimen (R‐CHOP) has improved DLBCL outcomes significantly, over 25% of patients treated with R‐CHOP unfortunately experience treatment failure . The early recognition of patients with a poor prognosis and the tailoring of their curative remediation plan are undoubtedly key interventions.…”

“…Although the addition of rituximab to a CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-like regimen (R-CHOP) has improved DLBCL outcomes significantly, over 25% of patients treated with R-CHOP unfortunately experience treatment failure. 1 The early recognition of patients with a poor prognosis and the tailoring of their curative remediation plan are undoubtedly key interventions. For the past 20 years, the International Prognostic Index (IPI) has been the basis for initial risk stratification for patients with CHOP-treated DLBCL, facilitating treatment selection and prognosis evaluation.…”

Interim PET/CT Result Is The Sole Prognostic Factor Of Survival In Patients With Advanced-Stage Diffuse Large B-cell Lymphoma：A Prospective Trial

“…To date, in DLBCL, PET predicts response, but more intensive chemotherapy has failed to improve outcomes for patients with iPET+ scans [8,9]. Several large prospective studies such as the PETAL and LYSA trials demonstrated that treatment intensification such as the Burkitt-type approach or autologous stem cell transplantation fail to prevent iPET+ patients from having a higher risk of relapse than iPETpatients [10]. RCHOP-like chemotherapies have been proven to be effective in DLBCL for many years.…”

Interim PET/CT based on visual and semiquantitative analysis predicts survival in patients with diffuse large B‐cell lymphoma

“…Varied timing of iPET/CT has been reported in the literature, and in most studies, iPET/CT was performed after two or four cycles of chemotherapy . Tumor glucose metabolism in the early stage of disease has been recognized as a favorable prognostic factor in DLBCL regardless of the times at which iPET is performed …”

“…[5][6][7] Tumor glucose metabolism in the early stage of disease has been recognized as a favorable prognostic factor in DLBCL regardless of the times at which iPET is performed. 8 Determining the best method to interpret iPET is also a significant challenge. Although Deauville 5-point scale (DS) was recommended as a standard method, the variable positive predictive value (PPV) of iPET using visual analysis is a main point of contention.…”