[Attempted marrow rescue with cryopreserved circulating stem cells following high-dose chemotherapy]

Circulating hematopoietic stem cells were collected by three consecutive leukaphereses during post-chemotherapy expansion of the stem cell pool in a 3-year-old boy with advanced and therapy-resistant neuroblastoma. The cells were fractionated by discontinuous Percoll gradient centrifugation, frozen in a programmed freezer and then stored in liquid nitrogen. Following high-dose chemotherapy, the cells were thawed rapidly and re-infused into the patient. Early evidence of marrow recovery was first noted at day 13 and the times required to achieve a granulocyte count of greater than 0.5 x 10(9)/L and a platelet count of greater than 50 x 10(9)/L were 21 days and 30 days, respectively. This new marrow-rescue operation may have potential in cancer therapy as an alternative to bone marrow transplantation and further clinical investigation is warranted.