Cryopreserved autologous bone marrow transplantation in the treatment of selected pediatric malignancies: a preliminary report.

We have shown that it is possible to collect and viably store sufficient numbers of stem cells to hematologically reconstitute patients following marrow-lethal doses of chemoradiotherapy. While no current procedure can be guaranteed to eliminate clonogenic tumor from the bone marrow, the fact that hematopoietic stem cells capable of reconstituting the host can be obtained after intensive chemotherapy makes it possible to clear microscopic foci of tumor from the marrow prior to storage. Such patients are now included in our protocol. The initial treatment results indicate that, in selected circumstances, tumor in otherwise refractory patients can be eliminated or partially controlled by a single intensive pulse of chemoradiotherapy with severe but acceptable extramedullary toxicity. The fact that patients can be rescued from otherwise lethal myelotoxicity by the reinfusion of cryopreserved autologous bone marrow permits wider exploration of new, more intensive cytoreductive regimens in a variety of cancers.