¹Servicio de Hematología, Universidad Autónoma de Madrid, Hospital Universitario Puerta de Hierro, Madrid, Spain

Correspondence: Professor MN Fernández, Department of Hematology, Hospital Universitario Puerta de Hierro, Universidad Autónoma de Madrid, San Martín de Porres, 4, 28035 Madrid, Spain. E-mail: manueln.fernández@uam.es

Received 30 June 2008; Revised 6 August 2008; Accepted 2 September 2008; Published online 13 October 2008.

Abstract

This open label clinical study provides updated evaluation of the strategy of single unit cord blood transplants (CBTs) with co-infusion of third-party donor (TPD) mobilized hematopoietic stem cells (MHSC). Fifty-five adults with high-risk hematological malignancies, median age 34 years (16–60 years) and weight 70 kg (43–95 kg), received CBTs (median 2.39 10⁷ total nucleated cell (TNC) per kg and 0.11 10⁶ CD34+ per kg) and TPD-MHSC (median 2.4 106 CD34+ per kg and 3.2 10³ CD3+ per kg). Median time to ANC and to CB-ANC >0.5 10⁹/l as well as to full CB-chimerism was 10, 21 and 44 days, with maximum cumulative incidences (MCI) of 0.96, 0.95 and 0.91. Median time to unsupported platelets >20 10⁹/l was 32 days (MCI 0.78). MCI for grades I–IV and III–IV acute GVHD (aGVHD) were 0.62 and 0.11; 12 of 41 patients (29%) who are at risk developed chronic GVHD, becoming severely extensive in three patients. Relapses occurred in seven patients (MCI=0.17). The main causes of morbi-mortality were post-engraftment infections. CMV reactivations were the most frequent, their incidence declining after the fourth month. Five-year overall survival and disease-free survival (Kaplan–Meier) were 56 % and 47% (63% and 54% for patients 40 years). In conclusion, CBT with single units of relatively low cell content and 0–3 HLA mismatches is feasible as a first choice option for adult patients who lack a readily available adequate adult donor.