Combination chemotherapy salvage of heavily pretreated patients with Hodgkin's disease: an analysis of prognostic factors in two chemotherapy trials and the literature.

The results of two intensive combination chemotherapy trials for heavily pretreated patients with Hodgkin's disease were markedly different. Only one of 27 patients treated with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) achieved a complete remission (CR), while a CR was attained by 50% of the patients (nine of 18) treated with ABVD alternating with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP/ABVD). There was a significantly longer survival for patients on MOPP/ABVD. Characteristics of patients in the two trials which might have at least partially explained these differing results were identified. The patients treated with ABVD all had prior histories of multiple relapses or continuous disease activity, while the majority of responding patients treated with MOPP/ABVD had few prior relapses and long disease-free intervals immediately prior to treatment. In the MOPP/ABVD trial, a trend toward a higher CR rate was found for patients with relapses confined to lymph nodes, compared with patients who had extranodal disease, although the difference lacked statistical significance. The characteristics of the patient population undergoing treatment must be considered in the interpretation of the results of chemotherapy salvage regimens for Hodgkin's disease.