The use of CD34(+)-selected PBPC after high-dose chemotherapy in breast cancer patients is associated with prolonged recovery time and increased infectious complications

High-dose chemotherapy with autologous stem cell rescue can result in autot ransplantation of tumor cells. A possible approach to reduce tumor cell con tamination is the positive selection of CD34(+) PBPC, but this might be ass ociated with a prolonged recovery time as well as an increased risk of infe ctious complications because of the loss of committed progenitor cells. To investigate this aspect, we compared two sequentially treated cohorts of hi gh-risk breast cancer patients. Both groups received the same high-dose che motherapy regimen followed by autologous peripheral stem cell transplantati on. Group I received CD34(+)-selected blood progenitor cells, and group TI received nonselected blood progenitor cells. We compared these two identica lly treated groups with regard to recovery time, need for blood products, i nfectious complications, need for antibiotic treatment, and length of the t ransplantation-related hospital stay. We found a prolonged recovery time fo r neutrophils up to 0.5 x 10(9)/L (14 days in the selected group/10 days in the nonselected group) and platelets up to 30 x 10(9)/L (29/12 days), asso ciated with an increased requirement for RBC transfusions (5/3 U) and plate let transfusions (10/2 U). The rate of severe infectious complications (2/0 ), the need for nonprophylactic antibiotic treatment (15/10), and the lengt h of the hospital stay (25/21 days) in group I were also increased. We conc lude that positive selection of PBPC should not be used routinely until ran domized studies show a clear long-term benefit of using CD34(+)-selected st em cell products in breast cancer patients.