1. ¹Department of Medicine, University of Calgary and Tom Baker Cancer Centre, Calgary, Alberta, Canada
2. ²Department of Oncology, University of Calgary and Tom Baker Cancer Centre, Calgary, Alberta, Canada

Correspondence: Dr DA Stewart, Departments of Medicine and Oncology, University of Calgary and Tom Baker Cancer Centre, 1331 – 29th Street NW, Calgary, Alberta, Canada T2N 4N4. E-mail: douglast@cancerboard.ab.ca

Received 20 April 2006; Accepted 18 August 2006; Published online 18 September 2006.

Abstract

To reduce costs and avoid inconvenient overtime work, our institution changed policy in September 2000 so that autologous stem cell apheresis products were stored overnight before cryopreservation rather than immediately processed. This retrospective review was conducted to evaluate the possible impact of this policy change on hematopoietic engraftment following autologous stem cell transplantation (ASCT). In total, 229 consecutive lymphoma patients who underwent a single, unpurged ASCT in Calgary between January 1995 and November 2003 were evaluated. Of these patients, 131 patients' autografts underwent immediate processing and cryopreservation before September 2000, and 98 patients' autografts underwent next-day cryopreservation after overnight storage following this date. Results of univariate and multivariate analyses demonstrated no adverse effect of overnight storage before cryopreservation on the number of days to initial engraftment of platelets or neutrophils, on the proportion of patients with low blood counts 6 months post-ASCT, or on lymphoma relapse rates or overall survival post-ASCT. These data suggest that overnight storage of the autograft before cryopreservation does not adversely affect graft viability or influence long-term disease status, and support the continued use of overnight storage of stem cells before cryopreservation as a convenient, cost reduction measure.