COST-EFFECTIVE USE OF AUTOLOGOUS BONE-MARROW TRANSPLANTATION - FEW ANSWERS, MANY QUESTIONS, AND SUGGESTIONS FOR FUTURE ASSESSMENTS

High dose chemotherapy with the support of autologous bone marrow tran splantation (ABMT) or peripheral blood progenitor cells (PBPC) has bee n increasingly used in a variety of haematological and epithelial canc ers over the last decade. The rationale of this approach is to overcom e the chemotherapy resistance of tumour cells by increasing the dose o f cytotoxic drugs. However, the clinical benefit of dose-intensificati on has been difficult to prove. Almost all studies of ABMT have been d one without randomised comparisons with the standard form of therapy f or a specific condition. From an economic perspective, the cost of ABM T has been steadily decreasing with improvements in supportive care pr imarily. Still, current ABMT cost estimates range from $US70 000 to $U S 150 000 for each uncomplicated procedure. Despite the lack of compel ling evidence in support of dose-intensification, ABMT has become a de fault standard of care after relapse for many patients with lymphoma o r leukaemia. We used a decision analysis model to estimate the cost ef fectiveness of the timing of ABMT in relapsed Hodgkin's disease. The m odel illustrates the difficulty of using available clinical trial data when follow-up of promising early reports is not available. The model showed that in most situations the optimal strategy is ABMT in second relapse despite growing consensus that immediate ABMT is the treatmen t of choice. ABMT for women with high-risk or early metastatic breast cancer is one of the most controversial areas in clinical oncology. In the US, several ongoing major randomised trials are addressing the ro le of ABMT in breast cancer. Using a Markov process we found that ABMT is the preferred strategy under almost all assumptions. The size of t he benefit and cost effectiveness of ABMT varied markedly depending on the assumptions made. The model does not supplant the need for random ised trials that concurrently measure efficacy, quality of life, and r esource utilisation. However, such analyses point out the critical are as where costs could be cut substantially without effecting efficacy. Drawing conclusions about the cost effectiveness of ABMT for all condi tions is hampered by the lack of randomised comparisons of efficacy. C oncurrent economic appraisals of selected phase Ill comparative trials should be considered since the supportive care costs associated with ABMT appear to be stabilising. However, the most important point is th at randomised trials are the only mechanism for estimating the therape utic effect of high dose chemotherapy.