ISY9-1 - Interim PET-CT-adapted treatment for malignant lymphoma

Abstract

Positron emission tomography-computed tomography (PET-CT) is widely used in the management of malignant lymphoma especially in staging and response assessment at the end of treatment. PET-CT provides more accurate information than conventional imaging studies including computed tomography (CT) and has been incorporated into essential imaging study for staging and response assessment in the recently published criteria (Lugano classification). In patients with advanced stage classic Hodgkin lymphoma (HL), results of interim PET-CT after 1-3 cycles of standard chemotherapy including ABVD have been shown to be predictive for prognosis when the patient continues the same regimen regardless of the result of interim PET-CT. Thus, it would be a reasonable approach to switch therapy to more intensive regimen such as escalated BEACOPP in patients with a positive interim PET-CT or less intensive regimen in patients with a negative result. Clinical trials to evaluate such an interim PET-CT-adapted approach have been conducted for advanced stage HL (SWOG S0816, UK RATHL, GITIL-FIL HD 0607). Results of these studies suggests that interim PET-CT-adapted intensified treatment may improve prognosis of patients with positive interim PET-CT. Moreover, in interim PET-CT-negative patients, omitting bleomycin, potentially pulmonary toxic agent, might be possible without jeopardizing prognosis. There are several challenges in incorporating interim PET-CT-adapted treatment in clinical practice in Japan. For instance, interpretation of PET-CT based on 5-point scale has not been widely accepted among PET-CT specialists. Japan Clinical Oncology Group is conducting a clinical trial (JCOG1305) to confirm the utility of PET-guided treatment strategy for previously untreated advanced stage HL.