[Long-term hematopoietic reconstitution after myeloablative antitumor therapy and circulating hematopoietic stem cell transplantation].
BACKGROUND
It remains unknown if hematopoiesis reconstituted by autografting with the sole peripheral blood hematopoietic progenitors (CPCs) after myeloablative high dose radiotherapy and/or chemotherapy is durable and capable of coping with increased demand due to boost radiotherapy, surgery, or infection.


METHODS
Durability of hematopoiesis was evaluated in 34 consecutive cancer patients treated with myeloablative total body irradiation (n = 17, median follow-up 3 years, range 3-49 months) and/or alkylating agent chemotherapy (n = 17, median follow-up 8 months, range 6-41 months) and autografted with CPCs because bone marrow autografting was contraindicated. CPCs (> or = 8 x 10(8) CD34+ cells/kg) had been collected during mobilization into the circulation in response to previous anticancer therapy and hematopoietic growth factor(s).


RESULTS
Following brief temporary pancytopenia, all patients achieved normal and durable hematopoiesis. The newly reconstituted hematopoietic system was capable of reacting favorably to stressful and noxious events such as surgery, radiotherapy, or varicella-zoster infection. No secondary irreversible failure of blood cell production occurred.


CONCLUSIONS
The documentation of the durability of normal hematopoiesis following myeloablative cancer therapy and autografting with mobilized CPCs implies that the latter procedure, rather than solely an alternative to bone marrow autografting, represents an advantageous tool of choice permitting substantial amelioration of the therapeutic index of high-dose cancer therapy.
Siena
S
S
Divisione di Medicina Oncologica, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milano.
Bregni
M
M
Di Nicola
M
M
Magni
M
M
Ravagnani
F
F
Gandola
L
L
Lombardi
F
F
Gianni
A M
AM
D015925:Cryopreservation; D006410:Hematopoiesis / Q000187:drug effects* / Q000528:radiation effects*; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007937:Leukapheresis; D007962:Leukocytes / Q000187:drug effects* / Q000528:radiation effects*; D009369:Neoplasms / Q000097:blood / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D012189:Retrospective Studies; D019172:Transplantation Conditioning