Long-term results of placental blood allografting using reduced-intensity conditioning: multicenter experience in a developing country.

BACKGROUND: Placental blood (PLB) hematopoietic stem cell transplantation has recently been explored in an increasing number of patients; the best conditioning regimen has not been established. MATERIAL AND METHODS: In an eight-year period, 66 consecutive patients, both children and adults (40 males and 26 females), were grafted with allogeneic placental blood cells using a reduced-intensity conditioning regimen: 23 patients were grafted because of a non-malignant condition and 43 patients for a malignant disease. The median age was 7 years (range 5 months to 72 years). RESULTS: Median time to recover >0.5×10(9)/l granulocytes was 19 days, whereas median time to recover >20×10(9)/l platelets was 23 days. Thirty-eight individuals failed to engraft and they either recovered endogenous hematopoiesis or died. Patients have been followed for periods ranging from 0.5 to 66 months, median 9 months. The median overall post-transplant survival (OS) was 22 months and the 36-month OS was 32%; it was significantly better for individuals grafted with 6/6 matched cords (45%). The cumulative incidences of grade II-IV acute graft-versus-host disease (GVHD) and grade III-IV acute GVHD for the patients who engrafted were 33 and 10%, respectively. DISCUSSION: The low engraftment rate should be improved by selecting better cord blood units; additional studies are needed to define if non-myeloablative conditioning is preferable over conventional conditioning.

Core binding factor acute myeloid leukemia (CBF-AML) in México: a single institution experience.

Twenty one patients with CBF-AML presented prospectively in the Centro de Hematología y Medicina Interna de Puebla (Puebla, México) between February 1995 and March 2010, 14 with the t(8;21)(q22;q22) and 7 with the inv(16)(p13;q22)/t(16;16)(p13;q22); they represent 13% of all cases of AML. The median age of the patients was 24 years (range 1 to 61). Seven of 14 patients with t(8;21)(q22;q22) had an M2 morphology whereas 3/7 with the inv(16) had an M4 morphology; in addition to the myeloid markers identified by flow-cytometry (surface CD13, surface CD33, and cytoplasmic myeloperoxidase) lymphoid markers were identified in the blast cells of 8/14 cases of the t(8;21) patients, but in no patient with the inv(16). Nineteen patients were treated with combined chemotherapy and 16 (84%) achieved a complete molecular remission. Seven patients were auto or allografted. Relapses presented in 10/16 patients. The median probability of overall survival (OS) has not been reached being above 165 months, whereas the 165-month probability of OS and leukemia-free survival was 52%; despite a tendency for a better outcome of patients with the t(8;21), there were no significant differences in survival of patients with either the t(8;21) or the inv(16). In this single institution experience in México, we found that the CBF variants of AML have a similar prevalence as compared with Caucasian populations, that the co-expression of lymphoid markers in the blast cells was frequent in the t(8;21) and that these two AML subtypes were associated with a relatively good long-term prognosis. Further studies are needed to describe with more detail the precise biological features of these molecular subtypes of acute leukemia.

The flow-cytometric DNA content of the plasma cells of patients with multiple myeloma is a prognostic factor: a single institution experience.

The flow-cytometric DNA content in the plasma cells of patients with multiple myeloma has been studied as a prognostic factor and contrasting results have been found. In a group of 45 patients with myeloma from a single institution, the DNA content of the malignant plasma cells was studied by means of flow cytometry: no patients were found to have hypodiploid DNA content, 14 patients had hyperdiploid DNA, and 31 patients were found to have diploid DNA. The overall survival of patients with hyperdiploid DNA was better than that of patients with diploid DNA: 93% at 85 months and 79% at 89 months, respectively; in both groups, the median overall survival has not been reached. No correlation was found between the DNA content and the International Staging System and the discriminatory effect of the DNA content was apparent only in the patients who were not autografted. It is concluded that the flow-cytometric DNA content of the plasma cells of patients with multiple myeloma may be a prognostic factor independent of others already identified and that myeloma patients with hyperdiploid DNA content in the plasma cells may have a better prognosis than those with a normal DNA content.

Poor hematopoietic stem cell mobilizers in multiple myeloma: a single institution experience.

In a single institution, in a group of 28 myeloma patients deemed eligible for autologous transplant, stem cell mobilization was attempted using filgrastim: 26 individuals were given 31 autografts employing 1-4 (median three) apheresis sessions, to obtain a target stem cell dose of 1 x 10(6) CD34 +ve viable cells / Kg of the recipient. The median number of grafted CD34 cells was 7.56 x 10(6) / Kg of the recipient; the range being 0.92 to 14.8. By defining as poor mobilizers individuals in which a cell collection of < 1 x 10(6) CD34 viable cells / Kg was obtained, a subset of eight poor mobilizers was identified; in two patients the autograft was aborted because of an extremely poor CD34 +ve cell yield (< 0.2 x 10(6) CD34 +ve viable cells / Kg of the recipient) after four apheresis sessions. The long-term overall survival of the patients grafted with > 1 x 10(6) CD34 +ve viable cells / Kg was better (80% at 80 months) than those grafted with < 1 x 10(6) CD34 +ve viable cells / Kg (67% at 76 months). Methods to improve stem cell mobilization are needed and may result in obtaining better results when autografting multiple myeloma patients.

Dimethyl sulfoxide-induced toxicity in cord blood stem cell transplantation: report of three cases and review of the literature.

Umbilical cord blood transplantation using nonmyeloablative conditioning is currently considered by many as a valid potential alternative for any patient who requires an unrelated donor allograft and who is without a suitably matched and readily available volunteer. Dimethyl sulfoxide (DMSO) has been used for years as a cryoprotectant agent; it acts by penetrating the cell and binding water molecules and it has been described as harmless for the individual who receives it in limited amounts. In this paper, we describe 3 cases of DMSO-induced toxicities and briefly review the most common adverse reactions of the DMSO when used as a cryopreservation agent for the long-term storage of cord blood cells. Two of the 3 cases had a dismal prognosis. A brief review of the literature is presented.