Stem-cell transplant preparative regimens

Owing to the relatively high probability of recurrent disease in patients receiving hematopoietic stem-cell transplantation (HSCT) for malignancies, further development of new preparative regimens is warranted. Based on the data presented, one can predict that it will continue to be difficult to identify HSCT regimens that are more effective. Incremental improvements are expected to be small, difficult to measure, and will require inclusion of very large numbers of patients. Controlled trials to evaluate the effectiveness of specific treatment regimens for specific groups of patients will require only centers with large numbers of patients or co-operative groups to successfully conduct these studies. Development of HSCT regimens with low mortality and a minimum of morbidity without compromising efficacy are needed. This may be accomplished through the use of agents to protect normal, non-hematopoietic tissues from regimen-related toxicity (RRT), further exploration and expansion of applications of targeted radiolabeled antibody approaches and mixed chimerism approaches. The future holds much work, but great promise, in the development of new HSCT regimens.