Comparative Effectiveness of Proton Therapy versus Photon Radiotherapy in Adolescents and Young Adults for Classical Hodgkin Lymphoma

James E Bates; Stephanie Terezakis; Christopher G Morris; Avani D Rao; Shuchi Sehgal; Rahul Kumar; Raymond B Mailhot Vega; Nancy P Mendenhall; Bradford S Hoppe

doi:10.14338/IJPT-21-00011.1

Comparative Effectiveness of Proton Therapy versus Photon Radiotherapy in Adolescents and Young Adults for Classical Hodgkin Lymphoma

Int J Part Ther. 2021 Jul 8;8(3):21-27. doi: 10.14338/IJPT-21-00011.1. eCollection 2022 Winter.

Authors

Affiliations

¹ Department of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, GA, USA.
² Department of Radiation Oncology, University of Minnesota, Minneapolis, MN, USA.
³ Department of Radiation Oncology, University of Florida, Gainesville, FL, USA.
⁴ University of Florida Proton Therapy Institute, Jacksonville, FL, USA.
⁵ Department of Radiation Oncology and Molecular Radiation Science, Johns Hopkins University, Baltimore, MD, USA.
⁶ School of Medical Sciences & Research, Sharda University, Greater Noida, India.
⁷ Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, USA.

Abstract

Purpose: Early stage (stages I-II) classical Hodgkin lymphoma (cHL) is a highly curable disease typically diagnosed in adolescents and young adults (AYAs). Proton therapy can also reduce the late toxicity burden in this population, but data on its comparative efficacy with photon radiotherapy in this population are sparse. We assessed outcomes in AYAs with cHL in a multi-institution retrospective review.

Materials and methods: We identified 94 patients aged 15 to 40 years with stages I and II cHL treated with radiotherapy as part of their initial treatment between 2008 and 2017. We used Kaplan-Meier analyses and log-rank testing to evaluate survival differences between groups of patients.

Results: A total of 91 patients were included in the analysis. The 2-year progression-free survival (PFS) rate was 89%. Of the 12 patients who experienced progression after radiotherapy, 4 occurred out-of-field, 2 occurred in-field, and 6 experienced both in- and out-of-field progression. There was no significant difference in 2-year PFS among AYA patients by radiotherapy dose received (≥ 30 Gy, 91%; < 30 Gy, 86%; P = .82). Likewise, there was no difference in 2-year PFS among patients who received either proton or photon radiotherapy (proton, 94%; photon, 83%; P = .07).

Conclusion: Our cohort of AYA patients had comparable outcomes regardless of radiotherapy dose or modality used. For patients with significant risk of radiation-induced late effects, proton therapy is a reasonable treatment modality.

Keywords: Hodgkin lymphoma; outcomes; pediatrics; proton therapy; radiation therapy.