Response Assessment Criteria and Their Applications in Lymphoma: Part 2

Abstract

Learning Objectives: On successful completion of this activity, participants should be able to describe (1) the diagnostic and predictive value of interim and end-of-treatment PET in HL and NHL; (2) the role of response-adapted therapy in the clinical management of lymphoma; and (3) the newly-emerging applications of interim and end-of-treatment PET in lymphoma.Financial Disclosure: The authors of this article have indicated no relevant relationships that could be perceived as a real or apparent conflict of interest. CME Credit: SNMMI is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to sponsor continuing education for physicians. SNMMI designates each JNM continuing education article for a maximum of 2.0 AMA PRA Category 1 Credits. Physicians should claim only credit commensurate with the extent of their participation in the activity. For CE credit, SAM, and other credit types, participants can access this activity through the SNMMI website (http://www.snmmilearningcenter.org) through January 2020.Interim and end-of-treatment PET/CT have become central to the evaluation of Hodgkin and non-Hodgkin lymphoma. This review article seeks to aid clinical decision making by providing an overview of available data on the diagnostic and prognostic value of PET/CT imaging for response assessment and pretransplant evaluation in lymphoma. The relative strengths and limitations of these techniques in various disease subtypes and clinical scenarios are explored, along with their current standards for reporting and latest developments. Particular attention is given to response-adapted therapy, which is emerging as a cornerstone of clinical management. CTandPETwi th 18 F-FDG have come to play integral roles in evaluating Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). Soon after the incorporation of CT into staging and response assessment criteria, the advantages of using PET's metabolic data in conjunction with CT's structural information for these applications began to become apparent. This combination was especially helpful in the staging and restaging of lymphoma. It was shown to reliably identify the 80%-95% of posttreatment residual masses that are nonmalignant, thereby sparing patients unnecessary therapy and morbidity, and it was shown to alter staging in 20% of cases, most frequently upstaging patients by better detecting bone marrow involvement (1,2).After the integration of PET into the International Working Group criteria in 2007, PET/CT was widely adopted as a first-line imaging tool for evaluating end-of-treatment response in lymphoma (3). Subsequent studies laid the groundwork for the Deauville 5-point scale (D5PS) criteria, designed for the visual interpretation of PET scans (4). This was expanded by the Lugano guidelines, which established PET/CT as the modality of choice for staging and response assessment in 18 F-FDG-avid subtypes of lymphoma but maintained CT as the preferred tool for the small histologic subset with low or variable avidity (5). These guidelines are pa...

Imaging of Early Response to Predict Prognosis in the First-Line Management of Follicular Non-Hodgkin Lymphoma with Iodine-131-Rituximab Radioimmunotherapy

“…The initial 2007 International Harmonization Project tumor response classifications have been updated, first with the 2009 Deauville 5-point scale (D5PS) and more recently by the 2014 Lugano Criteria, which incorporates the D5PS [28]. This standardization has allowed for unified, comparable response assessment and lead to numerous studies, across various lymphoma subtypes (including Hodgkin lymphoma), firmly establishing the prognostic importance of post treatment 18 F-FDG-PET/CT response and allowing for response adaptive therapies [29]. …”

Targeted PET imaging strategy to differentiate malignant from inflamed lymph nodes in diffuse large B-cell lymphoma

“…Cancer immunotherapies often induce massive immune cell infiltration and consequently cause pronounced inflammation in tumors, increasing local metabolism levels (49). This inflammatory phenomenon presents tremendous challenges for the traditional therapeutic response evaluation methods, which often use a high metabolic rate as an indicator for cancer progression (50,51). For DLBCL, immunotherapies such as checkpoint inhibitors (15) and CAR-T-cell therapy (16) are rapidly advancing in clinical development.…”

Circulating tumor DNA reveals genetics, clonal evolution, and residual disease in classical Hodgkin lymphoma

“…However, interim PET/CT results are inconsistent with the final outcome in ;20% to 30% of patients, who are thus still exposed to over-or undertreatment. 4 By identifying residual disease beyond the sensitivity of imaging and by specifically tracking tumor fingerprints, molecular methods hold the potential of complementing PET/CT in assessing tumor response. 5 However, molecular minimal residual disease has been so far inapplicable in lymphomas that lack a leukemic component, such as cHL.…”