Background: Prolonged remission can now be induced in the majority of patients with Hodgkin's disease with chemotherapy and/or irradiation. However, there is a significant proportion of patients in whom this approach fails, either at presentation or subsequently. Survival is the definitive endpoint to assess treatment efficacy. In this study, the survival patterns of a large group of consecutive patients treated in a single institution are presented.
Results: The overall median survival was 18.3 years. Clinical remission (complete remission plus good partial remission) was induced in 443 (85%); the median survival of patients in remission has not been reached. Fifty-eight patients achieved responses less than clinical remission with initial therapy (partial response) or had progressive disease, the median survival of this group being 1.4 years. With further therapy, remission was subsequently induced in 10; 5 are still alive, 5 have died between 1.9 years and 14.3 years. Twenty patients died before completion of therapy. Recurrence has been documented in 147 of the patients in remission (following initial therapy) over a median follow up period of 13 years (minimum 5 years). One hundred forty-three of these patients were retreated following recurrence (105 chemotherapy, 28 radiotherapy, 6 combined modality treatment and 4 surgery). Second remission was induced in 109/143 (76%). There was a trend towards better second remission induction in patients whose first remission was longer than 1 year (p = 0.06). The median duration of second remission was inferior to first remission duration (p < 0.001). There was no correlation between duration of first remission and survival following recurrence (p = 0.8) or with duration of second remission (p = 0.54). There was no significant difference in duration of second remission between patients who were initially treated with radiotherapy or chemotherapy (p = 0.3). The median survival following second remission was 12.0 years, being the same for patients with initially localized disease (stages I and II) treated with radiation alone and for patients with advanced Hodgkin's disease (stages III and IV) treated with chemotherapy. Survival after recurrence is significantly better for patients under 50 years at the time of recurrence (p < 0.001). Second recurrence was documented in 46 patients, third remission being reinduced in 22, the median survival of the latter being 5.1 years.
Conclusion: These results illustrate the importance of prolonged follow up in defining the clinical course of patients with HD and are vital for planning experimental chemotherapy at the time of treatment failure or recurrence.