A trend towards an increased incidence of chronic graft-versus-host disease following allogeneic peripheral blood progenitor cell transplantation: a case controlled study.

Allogeneic peripheral blood progenitor cell transplantation (alloPBPCT) is increasingly used as an alternative to bone marrow transplantation (alloBMT). Early data suggest that the incidence and severity of acute graft-versus-host disease (GVHD) following alloPBPCT is no higher than that seen with alloBMT, despite the increased number of cytotoxic T cells infused with mobilised blood. We compared 12 patients undergoing alloPBPCT with 12 well-matched alloBMT controls. All patients received identical GVHD prophylaxis. No T cell depletion or CD34 purification was performed. Median engraftment times for neutrophils >0.5 x 10(9)/l and platelets >20 x 10(9)/l were 14 and 12 (alloPBPCT) and 21 and 23 days (alloBMT), respectively (P = 0.0035 and P = 0.002). There was no difference in antibiotic requirements (P = 0.83), platelet support (P = 0.59) or days in hospital (P = 0.51). After alloPBPCT, five patients developed > or =grade II acute GVHD vs five patients after alloBMT (P = 0.99). There was one death (alloBMT) at 100 days and three at 1 year (all due to relapse). There was one death at 100 days with alloPBPCT, and 11 patients remain alive (range 9-21 months) to date. Chronic GVHD occurred in five patients in the PBPC arm and one patient in the BM arm (P = 0.14). This case-controlled analysis indicates that alloPBPCT results in more rapid engraftment kinetics but in no significant difference in transplant-related morbidity or mortality. There is no difference in the incidence of acute GVHD. However, there is a trend towards increased incidence of chronic GVHD in patients allografted with PBPC. Prospective randomised trials are required to determine further the role of alloPBPCT.