COMPARISON OF TREATMENTS FOR SYMPTOMATIC HODGKINS LYMPHOMA EMPLOYING DECISION-ANALYSIS

A decision analysis methodology was developed for addressing a comparison of immediate MOPP [mechlorethamine, vincristine, prednisone, procarbazine] chemotherapy without staging to staging followed by medically indicated chemotherapy (MOPP) or radiotherapy (XRT). The patients would have symptomatic Hodgkin''s lymphoma. Each test and therapy was previously described in terms of 15 toxicity categories. Each was assigned a probability of the occurrence over the 5 grades of toxicity. Each grade was assigned an expected duration of the toxicity for each test or therapy. Both actual probabilities and judgmental probabilities were used. Utilities for the 15 toxicity categories were solicited. The staging-test.sbd.morbidity outcomes only pertained to decision paths which were directed at a chance to receive XRT as the medically dictated therapy. Relative scalar weights were assigned to each grade IV toxicity of 0 utility by 3 physicians. An additive (linear) model was used to compute composite utilities for the paths. There were the following 3 different outcomes for these individuals in the initial analysis: MOPP immediately without staging; MOPP immediately, or if staging had proceeded to a negative bone marrow then further staging was preferred; staging in order to have any chance to receive XRT. When a lower toxicity program of presumed equal efficacy was substituted (ChlVPP) the decision changed so that all 3 participants now would receive ChlVPP instead of staging based on their personal preferences about morbidity outcomes. Decision analysis can contribute to selection between treatments based on differences in an individual''s preferences in regard to varying degrees and spectra of toxicity.