- Apheresis: This is a procedure to collect progenitor cells for later reinfusion. For this procedure, blood is collected through a catheter (plastic tube) placed in an arm vein. The blood is circulated through a cell-separating machine, where the white cells, including the progenitor cells, are extracted, and the red cells are returned to the patient through another catheter in the other arm. Apheresis is done after each of two cycles of paclitaxel/cyclophosphamide.