Radical radiotherapy as salvage treatment for relapse of Hodgkin's disease initially treated by chemotherapy alone: prognostic significance of the disease-free interval.
A study was performed to determine the effectiveness of radical radiation therapy (RT) in the treatment of patients with Hodgkin's disease who relapsed following initial treatment with chemotherapy alone. A retrospective review of patients treated at City of Hope National Medical Center between 1970 and 1987 revealed a total of 10 patients who received radical RT with curative intent as salvage therapy. Complete remission was achieved in eight of the ten patients. Patients had an overall 5-year actual survival of 60% and 10-year actuarial survival of 38%. Relapse-free survival was 30% at 5 years and at 10 years. For the five patients with a disease-free interval (DFI) of at least 12 months prior to radical RT, overall actual survival at 5 years was 100% and relapse-free survival was 60%. Three of the ten patients, all with a DFI > 12 months and in first relapse when undergoing radical RT, were long-term relapse-free survivors. Radical RT is an effective salvage regimen for select patients with advanced stage Hodgkin's disease who relapse following initial treatment with chemotherapy alone provided that relapse is limited to sites which can be encompassed by radical RT fields and the DFI is greater than 12 months. Review of other published series supports DFI > 12 months as a favorable prognostic factor. Comparison to other salvage regimens such as autologous bone marrow transplantation is limited. Reviews of other treatment modalities should perform subset analysis on patients with similar presentations to compare the relative effectiveness of various salvage approaches.