The role of radiotherapy (RT) in the management of advanced Hodgkin Lymphoma (HL) is inadequately defined in this era of functional imaging with PET scan. SWOG-S0816 treated advanced stage Hodgkin lymphoma patients with ABVD+/- escBEACOPP and no RT. We queried whether RT might have benefited patients in S0816 who would have met the GHSG-HD15 criteria for RT by simulating RT use as per HD15 criteria of PET + residual disease ≥2.5 cm. Receiver-operating-characteristics analyses were performed by varying disease-control rates within radiation fields and size cutoffs for residual disease. Among the 49 PET3+ S0816 patients, RT would have raised the 2-year PFS from 30.6% to 50.2-58.1% using three residual disease cutoffs (1.5, 2.0 and 2.5 cm) and assuming 80 and 90% in-field control rates . Although there may be improvement in PFS as size cutoff point is lowered, consequential toxicities from RT require further definition to assess relative benefits.
Keywords: Hodgkin lymphoma; PET (positron emission tomography); radiotherapy.