[High dose therapy with transplantation of autologous peripheral hematopoietic stem cells. I. Basic principles and clinical development].

High-dose therapy with peripheral stem cell rescue is increasingly being used as a salvage or consolidation therapy for patients with malignant disease. The accelerated hemopoietic recovery and the collection of peripheral stem cells in an outpatient setting are the main advantages. Recent findings on tumor cell contamination of autografts stimulated the development of techniques for tumor cell reduction, based on negative selection (purging) of tumor cells or positive selection of CD34+ progenitor cells. Purging and CD34 selection could probably result in increased cure rates. CD34 selection is also imperative for the successful expansion of progenitor cells in vitro. Using various mixtures of cytokines, different cell lineages may be preferentially expanded. A further area of interest is gene transfer into hematopoietic cells, where a purified cell population is a prerequisite for success. Future directions are the increase of cure rates by sequential administration of chemotherapeutic drugs at their maximum tolerated doses, the evaluation of new antineoplastic drugs and improved supportive care.