Hemopoietic progenitor cell transplantation: Twenty years of experience at the Postgraduate School of Hematology "Farreras-Valenti" Hospital Clinic of Barcelona

BACKGROUND: Hemopoietic progenitor cell transplantation (HPCT) is acquiring an increasing role in the therapy for a variety of disorders. In this study, main characteristics and results of HPCT along 20 years are analyzed from the experience of Postgraduate School of Hematology "Farreras-Valenti" at the Hospital Clinic in Barcelona. PATIENTS AND METHODS: Six-hundred ninety-five patients transplanted between June 1976 and January 1996 were analyzed. Median age (range) were 33 (4-63) years. The following aspects were considered: donor type, source or progenitor cells, type of disease and disease-stage at transplantation, transplant related mortality and survival. RESULTS: A total of 714 HPCT were performed (448 allogeneic, 13 isogeneic, 253 autogeneic). Allogeneic HPCT were from an HLA-identical sibling in 408 cases, from other familial donors in 10, and from non-familial donors in 30. Most HPCT from non-familial donors (93%) were performed during the last five yeas of the study (1991-1995). The source of hemopoietic progenitor cells was bone marrow in 625 instances (88%), peripheral blood in 88 (12%), and fetal liver in one. During more than 15 years, the only source of progenitors was the bone marrow; in contrast, in the last 3 years (1993-1995) transplants using peripheral blood were predominant. Main indications for HPCT were the following: acute leukemias (n = 387) (54%), chronic leukemias (n = 134) (19%), severe aplastic anemia (n = 58) (8%), lymphomas (n = 80) (11%), multiple myeloma (n = 39) (5%) and myelodysplastic syndromes (n = 14) (2%). In patients with hematological malignancies (n = 656), HPCT was performed in first complete remission or in first chronic phase in 321 instances (49%), in subsequent remissions in 144 (22%), and in more advanced stages in the remaining 191 (29%). In the more recent years, a progressive decrease in the number of HPCT far acute leukemia or aplastic anemia was observed, contrasting with an increase in transplants for lymphoma, multiple myeloma and myelodysplastic syndromes. Of note, a significant decrease in transplant related mortality was evident along the years, both after autogeneic HPCT (21% during 1985-1992 and 6% thereafter) (p = 0.001) and after allogeneic transplantation (54%, 44%, and 20% during the periods 1976-1984, 1985-1992 and 1993-1995, respectively) (p = 0.004). This fact translated into an increase in the actuarial probability of survival after allogeneic HPCT (25%, 33% and 58% in the three mentioned periods, respectively) (p = 0.0003), and after autogeneic HPCT (33% in the interim 1985-1992, and 55% in the period 1993-1995) (p = 0.001). CONCLUSIONS: During the last 20 years, HPCT has significantly evolved in aspects such as type of donor, source of progenitor cells and indications. Remarkably, a progressive decrease in transplant related mortality has been observed translating into a improvement in survival after the procedure.