Response to positron emission tomography (PET) scan after two cycles of standard treatment allows for early treatment adaption for patients with early-stage Hodgkin lymphoma, according to research published in the Journal of Clinical Oncology (June 2017;35:1786-1794).
Although standard treatment of early-stage Hodgkin lymphoma is generally very successful, a small clinically relevant subgroup of patients experience treatment failure or serious adverse events. Early response evaluation with PET scan may help identify patients who need reduced or more intensive treatments to avoid complications.
A group of multinational researchers conducted a randomized trial to evaluate treatment modification on the basis of early PET scan after two cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) in previously untreated stage I/II Hodgkin lymphoma. A total of 1950 patients were categorized as demonstrating either favorable or unfavorable disease – as per the European Organization for Research and Treatment of Cancer criteria. Patients were randomly assigned to either the standard arm—consisting of ABVD followed by involved-node radiotherapy, regardless of PET scan result—or the experimental arm – in which patients with PET-negative results received ABVD only and those with PET-positive results switched to two cycles of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone along with involved-node radiotherapy.
Primary endpoint of the trial was progression-free survival (PFS).
Results of the study showed that patients with PET-positive results after two cycles of ABVD benefited from significantly improved 5-year PFS after switching treatment regimens. In patients with PET-negative results, noninferiority of ABVD could not be demonstrated; risk of relapse significantly increased when involved-node radiotherapy was omitted, especially in the group of patients categorized as favorable.
Researchers concluded that these findings can have significant and immediate implications for improving care for early-stage Hodgkin lymphoma. By administering PET scans in the early stages of treatment, clinicians may alter therapy courses for individual patients to improve their treatment outcomes.—Zachary Bessette