Outcomes of allogeneic haemopoietic stem cell transplants at a small New Zealand centre: does size matter?

Reduced intensity conditioning (RIC) protocols for allogeneic haemopoietic cell transplants (HCT) have become commonplace treatments for patients with haematological disease, extending allogeneic HCT to older and less fit patients. There is a perception that centres treating larger numbers of patients have improved outcomes.

We wanted to examine whether outcomes for adult allogeneic HCT patients from our smaller centre were equivalent to those expected at larger centres internationally.

Clinical and laboratory data were collected on all patients who received allogeneic HCT during 2000-2012. Outcomes, including overall survival (OS) and progression-free survival, were compared between patients receiving myeloablative conditioning (MAC) and RIC protocols.

One hundred and eighteen adult patients underwent allogeneic HCT with MAC (n = 51) or RIC (n = 67). The mean age of patients receiving MAC (35.8 years, range 18-56) was lower than those receiving RIC (48.4 years, range 19-64). Two-year OS was similar for MAC and RIC patients (66% vs 62%, P = 0.17), whereas 2-year progression-free survival was superior in MAC patients (63% vs 50%, P = 0.01) due to fewer relapses. OS was reduced in older patients irrespective of conditioning. Patients with chronic graft-versus-host disease had improved survival due to fewer relapses. OS was unaffected by HCT comorbidity index, donor, cell source or patient/donor cytomegalovirus status.

RIC protocols have resulted in long-term survival in many patients ineligible for MAC protocols. In our smaller centre, patient age but not conditioning intensity influenced survival, which was equivalent to reports from larger centres.