The role of radiotherapy in Hodgkin's lymphoma: what has been achieved during the last 50 years?

Abstract

Currently, Hodgkin's lymphoma (HL) has an excellent clinical outcome, with overall survival of approximately 90% in early stages of the disease. Based on young age of the majority of patients at the time of diagnosis and their long survival time, increased attention has been focused on long-term toxicity of therapy. While novel, directly targeting antitumor agents, with an excellent safety profile, have been developed for HL treatment, the role of radiotherapy is still debated. Radiotherapy may induce cardiovascular disease and impairment of thyroid or pulmonary function and, most importantly, may lead to development of secondary cancers. As a consequence, the current radiation therapy planning paradigm is mainly focused on a reduction of field size. As it was investigated in clinical trials regional therapy is as effective as extended field radiotherapy, but less toxic. Although chemotherapy is the mainstay of HL treatment, consolidative involved field radiation therapy is still considered to be the standard of care in both early and advanced stages. Recently, further field reduction has been investigated to further decrease the late radiation-induced toxicity. In this paper we describe the role and safety profile of radiotherapy in the past and present and hope for the novel techniques in the future.

Figure 1

Schema for German HD10 and English RAPID Trial. ABVD: adriamycin, bleomycin, vinblastine, and dacarbazine, PET: positron emission tomography, IN-RT: involved nodal radiation therapy, IF-RT: involved field radiation therapy, escBEACOPP: bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone.

Figure 2

Images demonstrate changes in radiotherapy surface for HL. In this picture lymph nodes involved with HL disease are illustrated in red. In grey is depicted irradiated field region. (a) Involved lymph nodes, (b) mantle field, (c) IF-RT: involved field radiation therapy, and (d) IN-RT: involved nodal radiation therapy.