Aim: To examine changes in radiotherapy (RT) use, cause-specific survival (CSS), and overall survival (OS) in a population-based cohort of Hodgkin's disease (HD) patients diagnosed from 1982 to 1996.
Materials and methods: Adult patients with HD diagnosed from 1 January 1982 to 31 December 1996 (n = 3957) were identified from the Ontario Cancer Registry. The cohort was divided into three consecutive 5-year periods: 1982-1986, 1987-1991, and 1992-1996. RT use, CSS and OS in each of these three periods were compared. For the entire cohort, the cumulative incidence of different causes of death was calculated.
Results: The proportion of patients receiving RT within 11 weeks of diagnosis declined over the three consecutive periods (25.1%, 15.6%, 11.7%, P < 0.001), as did the proportion receiving RT within 45 weeks (57.0%, 51.0%, 48.1%; P < 0.001). There was a significant increase in 5-year CSS over time (81%, 87%, 89%; P < 0.001), and OS (72%, 77%, 82%; P < 0.001), which remained significant in multivariable analyses. The cumulative incidence of death from causes other than HD was equal to the incidence of HD-related death within 12 years of diagnosis.
Conclusions: There was a significant decline in the use of RT as the primary treatment modality and as part of the initial management of HD from 1982-1996 in Ontario. A greater proportion of patients received their RT after a delay consistent with the receipt of prior chemotherapy. There was also a significant increase in the CSS and OS over this period. These findings are in keeping with the adoption of effective chemotherapy in the treatment of HD.