Management and Outcomes for Patients With Hodgkin Lymphoma With Partial Metabolic Response After First-Line Systemic Therapy.

Abstract

To evaluate real-world management strategies and outcomes for patients with Hodgkin lymphoma (HL) with a partial metabolic response (PMR) on an end-of-chemotherapy (EOC) fluorodeoxyglucose-positron emission tomography (PET) scan and assess whether dynamic changes in maximum standardized uptake value (SUVmax) could refine risk stratification. Multicenter, retrospective cohort study of patients with HL treated from January 1, 2009, to September 30, 2021. PMR was defined as a Deauville score of 4 on the EOC-PET scan, with an SUVmax value lower than the staging PET scan. First-line chemotherapy was predominantly adriamycin, bleomycin, vinblastine, and dacarbazine (62.7%), or adriamycin, bleomycin, vinblastine, and dacarbazine-escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisolone (28.4%). The primary endpoint was progression-free survival (PFS). Cox proportional hazards models adjusted for stage and EOC-avid sites quantified outcomes; SUVmax value kinetics (interim-to-EOC) were explored within the radiation therapy (RT) cohort. Among 836 patients with EOC-PET scans, 67 met PMR criteria; median follow-up was 3.2 years (range, 0.1-12.6). Post-EOC-PET scan management included involved-site RT (n = 38), salvage chemotherapy ± autologous stem-cell transplantation (n = 14), or observation with serial PET scans (n = 12). RT recipients had more early-stage disease (55.3% vs 21.4%), fewer EOC-avid sites (median, 1 vs 2), and lower EOC SUVmax values (median, 4.7 vs 10.2) than those receiving systemic therapy. Two-year PFS was 84.2% after RT, 52.7% after salvage chemotherapy, and 74.1% with observation (log-rank P = .057). On multivariable analysis, salvage chemotherapy (hazard ratio [HR], 5.82; 95% CI, 1.14-29.81; P = .03) and observation (HR, 5.74; 95% CI, 1.12-29.39; P = .03) were associated with higher progression risk versus RT. Within the RT cohort, rising SUVmax values between interim and EOC-PET scans (HR, 7.21; 95% CI, 1.17-44.35; P = .033) and higher absolute EOC SUVmax values (HR per unit, 1.35; 95% CI, 1.02-1.79; P = .036) predicted inferior PFS. Most patients with HL with PMR achieve durable remission with consolidative RT alone, avoiding salvage chemotherapy and transplantation. Dynamic changes in SUVmax values-especially a rising SUVmax value between interim and EOC-PET scans-identify a high-risk subset potentially warranting treatment intensification. Prospective studies integrating novel agents and PET scan metrics are needed to personalize therapy for this population.