Definitive irradiation in the treatment of Hodgkin's disease. Analysis of outcome, prognostic factors, and long-term complications.
BACKGROUND: In the curative treatment of Hodgkin's disease, many institutions give doses above 40 Gray (Gy). To assess the effectiveness of treating patients with 35 Gy, data from a single institution regarding survival, prognostic factors, patterns of failure, and secondary complications were reviewed. METHODS: Data for a total of 172 patients with Hodgkin's disease were reviewed. All patients received definitive irradiation between 1971 and 1994. Median follow-up was 110 months. Kaplan-Meier methods were used to estimate survival, relapse-free survival, and complication rates. RESULTS: Relapse-free survival was 83% at 5 years and 76% at 10 years. The only two prognostic factors related to relapse-free survival were the stage of disease and the number of sites. The involved infield control rate was 96%. The 10-year estimates of hypothyroidism and second malignancies were 14% and 10%, respectively. CONCLUSIONS: Doses of 35 Gy are adequate for treating Hodgkin's disease. The stage of disease and the number of sites are predictive of relapse-free survival. The incidence of late complications necessitates long term surveillance of these patients.