Decreased quality of peripheral blood progenitors collected after a peripheral blood progenitor transplant

The purpose of this study was to determine the quality of peripheral blood progenitor cells (PBPC) collected after an initial autologous PBPC transpla nt. Tandem autologous transplants have been used in the treatment of severa l malignancies. Routinely, PBPC have been collected prior to the first tran splant and used for both transplants. In the current study, PBPC harvested prior to the first high-dose therapy (HDT) were used as a source of progeni tors for transplant 1, and a combination of bone marrow harvested prior to the first course of HDT and PBPC collected approximately 85 days after the first transplant were used to support the second HDT. We analyzed the quali ty of the PBPC collected 85-120 days after HDT and autologous PBPC transpla nt. CD34 and colony-forming units granulocyte-macrophage (CFU-GM) contents of those collections were poor, and hematopoietic recovery was more consist ent with recovery from a bone marrow transplant than a PBPC transplant. Thi rteen of 15 patients received both transplants. Days to absolute granulocyt e count of 500 was 10 +/- 1.5 for the first transplant and 13.3 +/- 3.7 for the second (p < 0.01). The number of days to platelet count of 20,000 was 14.3 +/- 10.7 for the first transplant and 18 +/- 7 for the second transpla nt (p = 0.066). The number of days of total parenteral nutrition (TPN) and intravenous morphine used by patients for the first and second transplants was similar, whereas the length of hospitalization was 21.8 +/- 3.6 for the first transplant and 27.6 +/- 7.8 for the second transplant (NS). In concl usion, it appears that the quality of PBPC collected following a previous P BPC transplant may be compromised.