Therapy results in pediatric Hodgkin lymphoma - does less mean better? Experience from a single children's oncology center

Abstract

Therapy results in pediatric Hodgkin lymphoma reflect remarkable progress in pediatric oncology. In the last decade, relevant development of new therapeutic options for children with refractory or relapsed disease has been made. In this study, we retrospectively analyzed therapy results and risk factors in children treated in a single oncology center according to five therapeutic protocols. Data from 114 children treated by a single institution between 1997 and 2022 were analyzed. Classic Hodgkin lymphoma therapy results were divided into four therapeutic periods: 1997-2009, 2009-2014, 2014-2019, and 2019-2022. For nodular lymphocyte-predominant Hodgkin lymphoma, data from one therapeutic protocol was analyzed. For the entire group, the 5-year probability of overall survival was 93.5%. There were no statistically significant differences between therapeutic periods. The occurrence of B symptoms at diagnosis and incidence of relapse were risk factors for death (p = 0.018 and p < 0.001). Relapse occurred in 5 cases. The 5-year probability of relapse-free survival for the entire group was 95.2%, without significant differences between groups. Patients treated between 1997 and 2009 had over a sixfold higher risk for events, defined as primary progression, relapse, death, or incidence of secondary malignancies (OR = 6.25, p = 0.086). The 5-year probability of event-free survival for all patients was 91.3%. Five patients died, and the most common cause of death was relapse. Modern therapeutic protocols in pediatric Hodgkin lymphoma are marked by excellent outcomes. Patients with disease relapses have a notably high risk of death, and the development of new therapeutic options for this group remains one of the main goals of current trials.

Keywords: Children; Hodgkin lymphoma; Radiotherapy; Survival; Therapeutic era.

Fig. 1

Schemas of four consecutive protocols analyzed in the study. a PGP-HD-97 protocol; b EuroNet-PHL-C1 protocol; c EuroNet-PHL-Interim protocol; d Euro-Net-PHL-LP1 protocol; TG 1 — therapeutic group 1; TG 2 — therapeutic group 2; TG 3 — therapeutic group 3; TG 4 — therapeutic group 4; B-DOPA — bleomycin, dacarbazine, vincristine, doxorubicin, prednisone; MVPP – nitrogranulogen, vinblastine, procarbazine, prednisone; RT — radiotherapy; OEPA — vincristine, etoposide, prednisone, doxorubicin; AR — adequate response; IR — inadequate response; ERA — early response assessment; COPP — cyclophosphamide, vincristine, procarbazine, prednisone; COPDAC — cyclophosphamide, vincristine, prednisone, dacarbazine; DECOPDAC — dacarbazine, etoposide, doxorubicin, cyclophosphamide, vincristine, prednisone; B — B symptoms, E — E-lesions; CVP — cyclophosphamide, vinblastine, prednisone

Fig. 2

Five-year pOS for children treated because of HL between 1997 and 2022 according to 5 consecutive protocols

Fig. 3

Five-year pRFS for children treated because of HL between 1997 and 2022 according to 5 consecutive protocols

Fig. 4

Five-year pEFS for children treated because of HL between 1997 and 2022 according to 5 consecutive protocols