Long-term outcome after radiotherapy alone for lymphocyte-predominant Hodgkin lymphoma: a retrospective multicenter study of the Australasian Radiation Oncology Lymphoma Group

Background: The curative potential of radiotherapy (RT) alone as initial treatment for patients with Stage I-II lymphocyte-predominant Hodgkin lymphoma (LPHL) has not been defined well.

Methods: Two hundred two patients who were treated between 1969 and 1995 were evaluated in a retrospective, multicenter study.

Results: Patient characteristics were as follows: The median age was 31 years, 75% of patients were male, 80% of patients had Ann Arbor Stage I disease, 1% of patients had bulky disease, 3% of patients had B symptoms, 1% of patients had extranodal involvement, and 80% of patients had supradiaphragmatic disease. The RT fields were a full mantle field in 52% of patients, less than a full mantle field in 24% of patients, an inverted-Y field in 17% of patients, less than an inverted-Y field in 3% of patients, and total lymph node irradiation in 3% of patients. The median dose was 36 Gray. The median follow-up was 15 years. The overall survival (OS) rate at 15 years was 83%, and freedom from progression (FFP) was observed in 82% of patients, including 84% of patients with Stage I disease and 73% of patients with Stage II disease. No recurrent LPHL and only 1 patient with non-Hodgkin lymphoma (NHL) were reported after 15 years. Adverse prognostic factors that were identified on multifactor analysis were as follows: for OS, age 45 years or older (P < 0.0005), the presence of B symptoms (P = 0.002), increasing number of sites (P = 0.015); for FFP, increasing number of sites (P = 0.002). No significant difference was found in FFP in a comparison of patients who received elective mediastinal RT with patients who did not receive mediastinal RT (P = 0.11). Causes of death at 15 years were LPHL in 3% of patients, NHL in 2% of patients, in-field malignancy in 2% of patients, in-field cardiac/respiratory in 4% of patients, and other in 6% of patients.

Conclusions: The current data suggested that RT potentially may be curative for patients with Stage I-II LPHL and raise the possibility that limited-field RT may be used without loss of treatment efficacy. Involved-field RT warrants further investigation for patients with early-stage LPHL.