Do G-CSF mobilized, peripheral blood-derived stem cells from healthy, HLA-identical donors really engraft more rapidly than do G-CSF primed, bone marrow-derived stem cells? No!

For more than a decade, the notion that peripheral blood-derived stem cells engraft more rapidly than bone marrow-derived stem cells after high-dose therapy has dominated our thinking. Recently, reports that granulocyte colony-stimulating factor (G-CSF) induces a proteolytic marrow microenvironment have provided mechanistic support for that belief, compelling us to review our own experience of 29 consecutive transplants with HLA-identical blood and marrow stem cells. In contrast to several reported randomized controlled trials, we found marrow stem cells engraft just as rapidly (median day 11 for granulocytes over 500/microl and median day 17 for platelets over 20,000/microl) as blood stem cells (median day 12 and median day 19, respectively) if the donor is treated with G-CSF in the same manner before marrow harvest as the donor is treated with G-CSF before leukapheresis.

Autologous stem cell transplantation for small cell lung cancer.

Small cell lung cancer usually responds to radiation and chemotherapy, but cures are infrequent. Autotransplantation attempts to increase cures by intensifying the effects of chemotherapy. We studied 103 patients receiving high-dose chemotherapy with autologous hematopoietic stem cell transplantation (SCT) for small cell lung cancer in 1989-1997 at 22 centers participating in the Autologous Blood and Marrow Transplant Registry.