Determining factors for the outcome of peripheral blood progenitor cells harvests

This is a pilot retrospective study to investigate the factors that may affect the collection of peripheral blood progenitor cells (PBPC). Sixty‐nine PBPC harvests in 18 cancer patients (median age 39.5:8 males and 10 females) were performed during marrow recovery after chemotherapy and hematopoietic growth factors. Median number of nucleated cells (MNC) collected were 13.3 (range 2.3–44.5) × 109 per session. Median CFU‐GM was 362 colonies (range 63–1,720) per 500,000 MNC. Neither sex, body weight, diagnosis, nor the number of days into leukapheresis was significantly associated with MNC and CFU‐GM. Older patients tend to have higher CFU‐GM in the PBPC harvests (P = .0437). Higher WBC on the day of harvest is significantly associated with higher yield of MNC after leukapheresis (P < .0001). Patients without any evidence of disease have significantly higher yield of MNC than those having local/distant metastases with or without marrow involvement (P = .0302 and .0446). For patients with metastatic disease, those with bone marrow involvement tend to have higher CFU‐GM than those without bone marrow involvement although the difference is not statistically significant (P = .0559). Those patients who have received only one, or three and more chemotherapy regimens have a higher yield of MNC than those who have only two previous chemotherapy regimens (P = .036 and .0324). The mechanism of PBPC mobilization is also discussed. In view of the limited patient number in this study, the results should be confirmed by larger studies. © 1996 Wiley‐Liss, Inc.