The Value of Central Review of Deauville Scores for Response Adapted Treatment Protocols for Hodgkin Lymphoma

Abstract

Response adapted treatment approaches are increasingly being utilized for patients with Hodgkin lymphoma. Early response on FDG-PET according to 5-point Deauville scoring (DS) can identify patients that may do well (DS of 1-3) with less intensive therapy or may benefit from escalation in chemotherapy or involved site radiotherapy (ISRT) (DS 4-5). However, the response adapted treatment approach assumes that the radiologist reviewing the FDG-PET scan is familiar with DS and experienced in the scoring approach which will impact the overall treatment of the patient. We investigated this issue by evaluating institutional versus central review of interim FDG-PET imaging from an international clinical trial in pediatric Hodgkin lymphoma. AHOD1331 (NCT02166463) is a randomized clinical trial for patients 2-21 years of age with newly diagnosed Stage IIB with bulk, III B or IV A/B classical HL; accrual was complete in August 2019. Patients were randomized between two different systemic therapies and underwent response assessment after 2 cycles of chemotherapy (PET 2) in order to categorize lesions as slow responding lesions (SRL) if DS of 4,5; SRL required ISRT at completion of treatment. Institutions reported a DS of target lesions on PET2 and submitted it with the images to for central review. Review consisted of two COG radiology reviewers for each case, with adjudication in cases of with discordance between the initial 2 central reviews. Levels of agreement were measured between institutional and central review, using nonweighted kappa (k) statistics. k values between 0.81 and 1.00 indicate very good agreement, 0.61 and 0.80 indicate good agreement, 0.41 and 0.60 indicate moderate agreement, and 0.21 to 0.4 indicate fair agreement. Among 570 scans reviewed to date, PET2 agreement between central and institutional review was good with a k of 0.70 (95% CI 0.62-0.77). Overall, 18% (20/109) of all cases with SRL and 8% (36/461) rapid responding lesions (RRL) were re-classified as RRL or SRL respectively by central review. Overall, 4% (20/570) would have been under treated by protocol criteria and 6% (36/570) would have been incorrectly assigned to ISRT in the absence of central review. Although there was “good agreement” between central review and institutional review of PET2, central review resulted in change in therapy for 10% of cases in AHOD 1331. For patients on and off clinical trials, additional resources should be allocated to ensure appropriate assessment of Deauville scores for patients with HL undergoing FDG-PET response-based treatment approaches.