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Biomedical subjects

D Caballero

Publications and source records attributed to D Caballero.

At least 37 records · Page 2Linked to original sources
PubMed2001

Favourable effect of the combination of acute and chronic graft-versus-host disease on the outcome of allogeneic peripheral blood stem cell transplantation for advanced haematological malignancies.

To assess the influence of graft-versus-host disease (GVHD) on the outcome of patients with advanced haematological malignancies (AHM) who received a primary, unmodified allogeneic peripheral blood progenitor cells transplant (allo-PBT) from a human leucocyte antigen (HLA) identical sibling donor, we analysed 136 patients with myeloid neoplasms (n = 70) or lymphoproliferative disorders (n = 66), transplanted at 19 Spanish institutions. Median age was 35 years (range 1-61). The cumulative incidence of relapse for all patients was 34% (95% CI, 26-42%), 41% (95% CI, 33-49) for patients without GVHD and 14% (95% CI, 3-25) (P = 0.001) for patients with acute and chronic GVHD. After a median follow-up of 11 months (range 2-49), 60 (44%) patients remained alive with an actuarial probability of overall survival and disease-free survival (DFS) at 30 months of 31% (95% CI, 21-41%) and 28% (95% CI, 17-39%) respectively. In patients surviving > 100 d, the low incidence of relapse in those with acute and chronic GVHD led to a DFS of 57% (95% CI, 38-76%) compared with a DFS of 34% (95% CI, 17-51%) in the remaining patients (P = 0.03). Our results indicate a reduced incidence of relapse for patients with AHM receiving an unmodified allo-PBT and developing acute and chronic GVHD, which results in an improved DFS.

Acute Disease↗
PubMed2001

Disparity for the minor histocompatibility antigen HA-1 is associated with an increased risk of acute graft-versus-host disease (GvHD) but it does not affect chronic GvHD incidence, disease-free survival or overall survival after allogeneic human leucocyte antigen-identical sibling donor transplantation.

Disparity for the minor histocompatibility antigen HA-1 between patient and donor has been associated with an increased risk of acute graft-versus-host disease (GvHD) after allogeneic human leucocyte antigen (HLA)-identical sibling donor stem cell transplantation (SCT). However, no data concerning the impact of such disparity on chronic GvHD, relapse or overall survival are available. A retrospective multicentre study was performed on 215 HLA-A2-positive patients who received an HLA-identical sibling SCT, in order to determine the differences in acute and chronic GvHD incidence on the basis of the presence or absence of the HA-1 antigen mismatch. Disease-free survival and overall survival were also analysed. We detected 34 patient-donor pairs mismatched for HA-1 antigen (15.8%). Grades II-IV acute GvHD occurred in 51.6% of the HA-1-mismatched pairs compared with 37.1% of the non-mismatched. The multivariate logistic regression model showed statistical significance (P: 0.035, OR: 2.96, 95% CI: 1.07-8.14). No differences were observed between the two groups for grades III-IV acute GvHD, chronic GvHD, disease-free survival or overall survival. These results confirmed the association between HA-1 mismatch and risk of mild acute GvHD, but HA-1 mismatch was not associated with an increased incidence of chronic GvHD and did not affect relapse or overall survival.

Acute Disease↗
PubMed2000

Cerebral toxoplasmosis and Guillain-Barré syndrome after allogeneic peripheral stem cell transplantation.

We report an unusual case of cerebral toxoplasmosis associated with Guillain-Barré syndrome (GBS) in a 25-year-old patient diagnosed with chronic myelogenous leukaemia (CML), who underwent a mismatched allogeneic peripheral stem cell transplantation (PSCT). On day +83 he started with fever, and 7 days later tremor, muscular weakness, diplopia, dysarthria, respiratory difficulty, and universal arreflexia appeared, compatible with GBS. As the patient had a positive cytomegalovirus (CMV) antigenemia, this was the aetiology suspected for his neurologic findings, but specific treatment failed to improve his clinical situation, and he died on day +123. Necropsy demonstrated cerebral toxoplasmosis and axonal degeneration of nerve roots compatible with the axonal form of GBS. Interestingly, the polymerase chain reaction (PCR) signal for Toxoplasma gondii in two different cerebrospinal fluid (CSF) samples had been negative. In addition, this case showed unique magnetic resonance imaging (MRI) abnormalities. We conclude that a negative PCR on CSF cannot exclude toxoplasmosis in a transplant patient, and we emphasise the importance of considering Toxoplasma as an aetiology of fever and neurological symptoms in the transplant setting.

Adult↗
PubMed2000

Allogeneic peripheral blood cell transplantation for hypereosinophilic syndrome with myelofibrosis.

Patients with hypereosinophilic syndrome (HES) display a very heterogeneous clinical picture ranging from asymptomatic cases to very aggressive forms. We report a 38-year-old woman with progressive HES who developed severe myelofibrosis and was treated by allogeneic stem cell transplantation, using peripheral blood (PBSCT) instead of bone marrow as the source of progenitor cells, after conditioning with cytoxan and busulphan. To the best of our knowledge, this is the first case of HES with myelofibrosis treated with PBSCT. The patient remains alive 8 months post-PBSCT, and bone marrow fibrosis has significantly decreased following transplantation. Bone Marrow Transplantation (2000) 25, 217-218.

Adult↗
PubMed2000

Are myeloma patients with renal failure candidates for autologous stem cell transplantation?

INTRODUCTION: Renal function is one of the most important prognostic factors in multiple myeloma (MM). Patients with renal failure are generally excluded from high dose therapy even though they display a poor prognosis with conventional chemotherapy schemes. The aim of this study was to analyze the outcome of MM patients with renal insufficiency undergoing autologous stem cell transplantation (ASCT), including the evaluation of the quality of PB stem cell collections, kinetics of engraftment, transplant-related mortality, response to high dose chemotherapy and survival. MATERIALS AND METHODS: From a total of 566 valuable patients included in the MM Spanish ASCT registry, three groups of patients were defined: group BA, patients with abnormal renal function at diagnosis but normal at transplant (73 cases); group BB, patients with abnormal function both at diagnosis and at transplant (14 cases); and group AA (control group, 479 cases), patients who constantly had normal renal function. RESULTS AND CONCLUSION: Patients from groups BA and BB presented with a significantly higher number of adverse prognostic factors, reflecting that we were dealing with high tumor MM cases, as compared with patients from group AA. The number of mononuclear cells, CD34+ cells and CFU-GM cells collected in patients with non-reversible renal insufficiency was similar to those harvested in MM patients with normal renal function. Moreover, neutrophil and platelet engraftments were identical in patients with and without renal failure (days +11 and +12, respectively). By contrast, transplant-related mortality (TRM) was significantly higher in group BB patients (29%) than in groups BA (4.1%) and AA (3.3%). In multivariate analysis only three variables showed independent influence on TRM: poor performance status (ECOG 3), hemoglobin <9.5 g/dl and serum creatinine > or =5 mg/dl. The response to high dose therapy was independent of renal function. Interestingly, 43% of patients from group BB showed an improvement in renal function (creatinine < 2 mg/dl) after transplant. The three-year overall survival from transplantation was 56, 49 and 61% for the BB, BA and AA groups, respectively, with a statistically significant difference favoring group AA (P<0.01). PFS did not differ significantly between the three groups of patients. In multivariate analysis the only unfavorable independent prognostic factors for overall survival were poor performance status either at diagnosis or at transplant, high beta(2)-microglobulin levels, and no response to transplant. According to these results, ASCT is an attractive alternative for MM patients with renal insufficiency, and it should not constitute a criterion for exclusion from transplant unless patients display poor performance status and very high creatinine levels (>5 mg/dl).

Adult↗
PubMed2000

Conditioning regimens in autologous stem cell transplantation for multiple myeloma: a comparative study of efficacy and toxicity from the Spanish Registry for Transplantation in Multiple Myeloma.

High-dose chemoradiotherapy conditioning regimens for autologous stem cell transplantation (ASCT) are generally held to give similar results in multiple myeloma (MM), but no specific comparative study has been published. We addressed this issue by comparing the main high-dose chemoradiotherapy regimens used in the Spanish Registry. Patient cohorts included 315 cases treated with 200 mg/m2 melphalan (MEL200), 127 patients with 140 mg/m2 melphalan plus total body irradiation (MEL140 + TBI) and 121 cases with 12 mg/kg busulphan plus 140 mg/m2 melphalan (BUMEL). After ASCT, granulocyte and platelet recovery time was similar in all conditioning groups. There were no differences in transplant-related mortality. All regimens yielded a similar response in reference to pre-ASCT MM status, although BUMEL produced a slightly better overall response when compared with the other regimens (97% vs. 89% and 92%, P = 0.003). The 5-year overall survival (OS) with BUMEL was 47% [95% confidence interval (CI) 26-68] compared with 43% (CI 31-54) for MEL140 + TBI and 37% (CI: 18-56) for MEL200. The median survival for the BUMEL group was 64 months compared with 45 and 37 months for the MEL200 and MEL140 + TBI groups respectively. These differences were non-significant (P = 0.2). The median event-free survival (EFS) was better for BUMEL (32 months) than for MEL200 (22 months) or for MEL140 + TBI (20 months). The differences in EFS between BUMEL and the other conditioning regimens reached statistical significance (P = 0.01). Nevertheless, the adjusted multivariate analysis for OS and EFS revealed that the conditioning regimens had no independent prognostic value. We concluded that three different conditioning regimens, commonly used for ASCT in MM, have a similar antimyeloma effect. However, the trend for better results observed in our series with BUMEL requires a prospective trial.

Busulfan↗
PubMed2000

Allogeneic peripheral stem cell transplantation in a case of hereditary sideroblastic anaemia.

We report on a case of pyridoxine refractory hereditary sideroblastic anaemia (HSA) in a 19-year-old man who underwent peripheral blood stem cell transplantation (PBSCT) from his HLA-identical brother. By using short tandem repeat polymorphism, 100% donor cells were observed in peripheral blood on day +21; bone marrow showed mixed chimaerism from day +21 to day +221, when 100% cells of donor origin were observed. The patient developed extensive chronic graft-versus-host disease with favourable response to treatment. When the haemoglobin range was normal, a programme of phlebotomies reduced serum ferritin levels. Three years after transplantation, the patient has an ECOG rating of 0, with completely normal haemoglobin values (15 g/dl). To our knowledge, this is the first PBSCT reported in a case of hereditary sideroblastic anaemia.

Adult↗
PubMed1999

Haematopoietic damage persists 1 year after autologous peripheral blood stem cell transplantation.

In the present study we have used cell culture assays in order to assess the damage in the haematopoietic system 1 year after peripheral blood stem cell transplantation (PBSCT), and to establish at what level, haematopoietic progenitor cells (HPC) or stroma, this damage occurs. Thirty-one patients, nine breast cancer (BC), 17 non-Hodgkin lymphoma (NHL) and five Hodgkin disease (HD), who had received autologous PBSCT were included. Forty-eight normal subjects who had given informed consent were used as controls. Results were also compared with a matched group of patients (25 cases) prior to PBSCT. Progenitor cells were analysed using CFU-GM and plastic adherent delta (Pdelta) assays. Long-term bone marrow cultures (LTBMC) in one and two stages were established. One year after transplant both the number of committed progenitor cells and the CFU-GM production in LTBMC were significantly reduced in the three groups of patients when compared with controls (P < 0.05 or P < 0.01). Two-stage LTBMC experiments showed that the impairment in CFU-GM production was due to damage in both patients' stroma and haematopoietic progenitor cells (HPC). All patients, except those with HD, showed a decreased stromal layer confluence (P < 0.05), with significant differences in cell composition as compared to normal bone marrow (P = 0.001). When all these variables were compared with pretransplant results, we observed that stroma formation was significantly lower after PBSCT (P < 0.05), while the number of progenitor cells analysed by the Pdelta assay was significantly increased (P < 0.05). We can conclude that even 1 year after PBSCT, both the committed HPC and BM stroma remain damaged.

Adolescent↗
PubMed1999

Clinical significance of CD34+ cell dose in long-term engraftment following autologous peripheral blood stem cell transplantation.

The number of CD34+ cells has been described as the best parameter for predicting the quality of engraftment in peripheral blood progenitor cell (PBPC) transplantation in the early post-transplant period. In this study we have determined the optimal number of CD34+cells in order to maintain engraftment in the long term in a series of 100 patients receiving autologous PBPC transplantation. Based on our previous experience on the speed of early hematopoietic recovery, four subgroups of patients were established: patients infused less than 0.75 x 106/kg CD34+ (n = 9), 0.75 to 1.25 (n = 24), 1.25 to 2.0 (n = 37) and more than 2.0 (n = 30). These groups were designated as low, intermediate-low, intermediate-high and high CD34 groups, respectively. Transitory loss of neutrophil engraftment was observed in 67%, 30%, 16% and 6% of patients in the four mentioned CD34 groups respectively, with statistically significant differences between the different groups. Significant differences were also observed between the low CD34 group and the rest of the groups as regards platelet and red blood cell transfusion requirements, fever episodes, days of hospitalization and antibiotic requirements throughout the first year. Our results show that the dose of CD34+ cells influences engraftment also in the late post-transplant period, and correlates with transfusion and antibiotic requirements, fever episodes and days of hospitalization during the first year post-transplant.

Anti-Bacterial Agents↗
PubMed1999

Population pharmacokinetics of amikacin in patients with haematological malignancies.

The aim of this study was to analyse the pharmacokinetic behaviour of amikacin in patients with haematological malignancies using a mixed-effect model and sparse data collected during routine clinical care. The patient population comprised 207 haematology patients divided into two groups: one for computing the population model (n = 134) and the other for validation (n = 73). A one-compartment model was used and the following covariates were tested for their influence on clearance and volume of distribution: age, gender, weight, parenteral nutrition, creatinine clearance, stage of antineoplastic treatment (induction, consolidation, intensification), number of weeks postchemotherapy, clinical diagnosis, Eastern Cooperative Oncology Group score, neutropenia, hypoalbuminaemia, concomitant medication (vancomycin and/or amphotericin B), overhydration, and autologous or allogenic bone marrow transplant. The nonlinear mixed-effect model (NONMEM) was used to assess the population pharmacokinetic model of amikacin in these patients. Apart from bodyweight and renal function, acute myeloblastic leukaemia and hypoalbuminaemia proved to be the most important covariates explaining the interindividual variability in amikacin pharmacokinetics in patients with haematological malignancies. The predictive performance of this population model for amikacin serum concentrations seems suitable for clinical purposes.

Adult↗
PubMed1999

Large two-dimensional sonic band gaps.

We show that absolute sonic band gaps produced by two-dimensional square and triangular lattices of rigid cylinders in air can be increased by reducing the structure symmetry. In the case of square lattices, symmetry reduction is achieved by a smaller diameter cylinder placed at the center of each unit cell. For triangular lattices the reduction is achieved by decreasing the diameter of the cylinder at the center of the hexagons in the lattice. Theoretical predictions are also demonstrated experimentally: starting from a honeycomb lattice (using cylinders of 4 cm of diameter size and 6.35 cm nearest-neighbor distance) we have studied the transition to a triangular symmetry by putting rods with increasing diameter (in the range 0.6-4 cm) at the center. The greatest enhancement of the attenuation strength observed in transmission experiments has been obtained in the high frequency region for diameter ratios in the range 0.1-0.3.

Journal Article↗
PubMed1999

Neurological complications after autologous stem cell transplantation.

INTRODUCTION: Autologous bone marrow (BMT) or peripheral blood stem cell transplantation (PBSCT) are increasingly used to treat hematological malignancies and solid tumors. The reported incidence of neurological complications varies greatly among the different centers, ranging from 11 to 39%. PATIENTS AND METHODS: In order to gain insight into the real incidence of early neurological complications (first 6 weeks) after autologous transplantation, we analyzed a series of 254 patients who underwent BMT/PBSCT for hematological malignancies (212 cases) or solid tumors (42 cases). RESULTS: Seven patients died during the early posttransplant period (incidence: 2.4%), and one of these deaths was related to a neurological complication. Eight patients developed neurologic complications (incidence: 2.8%). None of the patients developed cerebral hemorrhage during the early posttransplant period, despite a rather restrictive platelet transfusion support. Two out of 13 patients diagnosed AML and 3 out of 36 patients diagnosed Hodgkin's disease developed early neurological complications. DISCUSSION AND CONCLUSIONS: The neurological morbidity related to autologous transplantation was very low in our series of patients as compared to that reported in previous studies. This difference could be explained, at least in part, by a more restrictive definition of early neurologic complications.

Adolescent↗
PubMed1999

Randomized prospective study comparing cost-effectiveness of teicoplanin and vancomycin as second-line empiric therapy for infection in neutropenic patients.

BACKGROUND AND OBJECTIVE: The current health-care philosophy dictates that new therapies should always be evaluated for their economic impact. Along with acquisition cost, the cost of delivery, monitoring, adverse effects and treatment failure must also be considered when determining the total cost of therapy. These auxiliary costs can be significant and greatly alter the overall cost of a drug treatment. We conducted a prospective randomized study to evaluate the efficacy, safety and cost of vancomycin and teicoplanin therapy in patients with neutropenia, after the failure of empirical treatment with a combination of piperacillin/tazobactam and amikacin. DESIGN AND METHODS: Seventy-six febrile episodes from 66 patients with hematologic malignancies under treatment, neutropenia (neutrophils <500/mm3) and fever (38 degrees C twice or 38.5 degrees C once) resistant to the combination piperacillin/tazobactam and amikacin were included in the study. RESULTS: Primary success of second-line therapy was obtained in 35 cases (46%) with no significant difference between vancomycin (17/38) and teicoplanin arms (18/38). No difference in renal or hepatic toxicity related to the antibiotic therapy was observed. The average cost per patient according to glycopeptide used was $450+/-180 for the teicoplanin group and $473+/-347 for the vancomycin group. Interestingly, in the teicoplanin arm, drug acquisition accounted for 97% of the total cost, while in the vancomycin arm administration and monitoring play an important role in overall costs. INTERPRETATION AND CONCLUSIONS: In conclusion, our pharmacoeconomic analysis demonstrates that teicoplanin and vancomycin can be administered in neutropenic hematologic patients with similar efficacy and direct costs.

Amikacin↗
PubMed1998

Autologous peripheral blood stem cell transplantation for multiple myeloma: a report of 259 cases from the Spanish Registry. Spanish Registry for Transplant in MM (Grupo Español de Trasplante Hematopoyético-GETH) and PETHEMA.

Between January 1989 and November 1995, 259 patients with multiple myeloma (MM), 22 stage I, 57 stage II and 180 stage III at diagnosis were treated with myeloablative high-dose therapy followed by autologous peripheral blood stem cell (PBSC) transplantation. The median time from diagnosis to transplantation was 17 months (6-112). At the time of transplant, 56 patients were in CR, 153 in PR, 25 were nonresponders and 25 had progressive disease. Mobilization of stem cells was performed with G-CSF alone in 141 cases, chemotherapy plus G-CSF in 65, chemotherapy plus GM-CSF in 36 and chemotherapy alone in 17 patients. The conditioning regimen consisted of high-dose melphalan alone in 96 patients, melphalan plus TBI in 73, busulfan plus melphalan in 56, busulfan plus cyclophosphamide in 27 and cyclophosphamide plus TBI in seven. The median durations of neutropenia (>0.5 x 10(9)/l) and thrombocytopenia (>20 x 10(9)/l) were 12 (5-118) and 13 days (5-360), respectively. Transplant-related mortality occurred in 11 patients (4%). Once a stable graft was achieved, 114 patients (44%) received maintenance treatment with recombinant alpha interferon (IFN-alpha). Among the 248 patients evaluable for response 125 (51%) had a CR and 100 had a PR (40%). The median duration of progression-free survival (PFS) and overall survival (OS) after transplantation was 23 and 35 months, respectively. Univariate analysis showed that response status pretransplant, only one line of primary induction treatment and IFN-alpha maintenance treatment post-transplant significantly influenced OS. Female sex, pretransplant responsive disease, and treatment with IFN-alpha post-transplant were the factors significantly influencing PFS. The conditioning regimen and method of stem cell mobilization had no significant impact on OS and PFS. On multivariate analysis the only independent factors associated with a longer survival were the number of chemotherapy courses prior to autologous PBSC transplantation and the pretransplant response status. The present analysis from the Spanish Registry confirms the feasibility of autologous PBSC transplantation in myeloma patients with a very low toxicity (4% toxic deaths). The high complete response rate after transplantation is encouraging. The best results are obtained when the procedure is performed early after the first line of induction therapy and in patients with chemosensitive disease. Whether early high-dose therapy followed by autotransplantation in responding patients is superior to conventional chemotherapy is currently being investigated in prospective randomized studies.

Adult↗
PubMed1998

Allogeneic transplantation of selected CD34+ cells from peripheral blood: experience of 62 cases using immunoadsorption or immunomagnetic technique. Spanish Group of Allo-PBT.

The objective of this study was to analyze CD34+ cell recovery and T cell depletion (TCD) achieved in CD34+ cell grafts using either immunoadsorption or immunomagnetic methods applied to leukapheresis products from healthy donors. We also wanted to determine the kinetics of engraftment and incidence and severity of graft-versus-host disease (GVHD) after allogeneic transplantation of selected CD34+ cells. HLA-identical sibling donors received G-CSF. After leukapheresis, peripheral blood progenitor cells were selected using immunoadsorption (Ceprate SC) (n = 38) or immunomagnetic (Isolex 300) (n = 24) methods. Sixty-two patients, with a median age of 42 years (range 17-60) diagnosed with hematological malignancies were conditioned with either cyclophosphamide and total body irradiation (n = 43) or busulphan and cyclophosphamide (n = 19). GVHD prophylaxis consisted of cyclosporin A (CsA) and prednisone (n = 48), CsA alone (n = 11) and CsA and methotrexate (n = 3). The median yield and purity of CD34+ cells after the procedure was 65 and 66% with immunoadsorption, and 48 and 86% with immunomagnetic method, respectively. The median number (range) of CD34+ cells infused into the patients was 3.5 x 10(6)/kg (1-9.6). The median number (range) of CD3+ cells administered was 0.4 x 10(6)/kg (0.01-2) using immunoadsorption and 0.14 x 10(6)/kg (0.03-2.5) using immunomagnetic methods. Neutrophil recovery >500 and >1000/microl was achieved at a median (range) of 13 days (8-22) and 14 days (9-31), respectively. Platelets recovered to >20000 and >50000/microl at a median (range) of 13 days (0-128) and 18 days (0-180), respectively. Two patients developed graft failure. Acute GVHD in patients at risk was clinical grade 0 (n = 43), I (n = 8), II (n = 4) and III (n = 1). No patient developed acute GVHD grade IV. Chronic GVHD was limited in two cases and extensive in four cases. The actuarial probability of acute GVHD II-IV was 10% (95% CI, 1-19%), and of extensive chronic GVHD was 12% (95% CI, 11-13%). The cumulative incidence of transplant-related mortality was 12.6%, and this figure was 9% at 6 months. In conclusion, with the immunomagnetic procedure, a lower recovery and higher purity of CD34+ cells, and stronger TCD is obtained as compared to immunoadsorption (P = 0.008, P < 0.0001 and P = 0.0002, respectively). Our results also indicate that allogeneic transplantation of selected CD34+ cells is associated with a very rapid engraftment and with a low incidence of severe GVHD.

Acute Disease↗
PubMed1998

Immunophenotypic characterization of plasma cells from monoclonal gammopathy of undetermined significance patients. Implications for the differential diagnosis between MGUS and multiple myeloma.

Although the immunophenotype of plasma cells (PCs) from multiple myeloma (MM) patients has been extensively explored, information on the phenotypic characteristics of PCs in monoclonal gammopathy of undetermined significance (MGUS) patients is scanty and frequently controversial. Thus, the question of whether or not PCs are phenotypically different in the two disorders and whether this criteria could be useful for the differential diagnosis between MGUS and MM remains to be explored. In the present study, the immunophenotypic profile of bone marrow PCs (BMPCs) from a group of 76 MGUS patients has been analyzed by flow cytometry and compared with that of BMPCs present in both MM patients (n = 65) and control subjects (n = 10). For that purpose, a large panel of monoclonal antibodies against PC-related antigens was used together with a sensitive methodology in which a minimum of 10(3) PCs were studied. In all MGUS cases studied, two clearly defined and distinct PC subpopulations could be identified. One PC subpopulation, population A (33 +/- 31% of total PCs), constantly displayed a high CD38 expression with low forward light scatter (FSC)/side light scatter (SSC) and was positive for CD19 and negative for CD56 (only a small proportion of these PCs were weakly positive for CD56). The other PC subpopulation, population B (67 +/- 31% of total PCs), showed the opposite pattern; the antigen CD56 was strongly positive and CD19 was constantly negative, and it showed a lower CD38 expression and higher FSC/SSC values than population A. Clonality studies (cytoplasmic light chain restriction, DNA content studies, and polymerase chain reaction assessment) confirmed the clonal nature of PCs from population B and the polyclonal origin of PCs from population A. Moreover, the polyclonal PCs from MGUS displayed a phenotypic profile identical to that found in PCs from healthy individuals. By contrast, clonal PCs from all MGUS patients displayed a similar antigenic profile to myelomatous PCs, with clear phenotypic differences with respect to normal PCs: lower intensity of CD38 expression and a variable reactivity for markers that were not expressed in normal PCs, such as CD28, CD117, and sIg. Although the presence of residual polyclonal PCs was a constant finding in MGUS patients, it was a rare event in MM and, when present (only 22% of MM cases), its frequency was significantly lower than that observed in MGUS (0.25% versus 32.9%, respectively; P < 0.0001). Only 1.5% of patients with MM had more than 3% of normal PCs, whereas 98% of patients with MGUS had more than 3%. Moreover, as shown by multivariate analysis, the number of residual polyclonal PCs was the most powerful single parameter for the discrimination between MGUS and MM patients at diagnosis, even when only stage I MM cases were considered.

Adult↗
PubMed1998

Allogeneic transplantation of purified CD34+ cells from peripheral blood: Spanish experience of 62 cases. Spanish Group of allo-PBT.

This report summarizes the Spanish experience of 62 cases of allogeneic transplantation of purified CD34+ cells from peripheral blood. HLA-identical sibling donors received G-CSF. After leukapheresis, peripheral blood progenitor cells were purified using one of two methods: Ceprate (n = 38), or Isolex 300 (n = 24). Sixty-two patients median age 42 years (range 17-60) diagnosed with hematological malignancies were conditioned with either cyclophosphamide and total body irradiation (n = 43) or busulphan and cyclophosphamide (n = 19). GVHD prophylaxis consisted of cyclosporin A (CsA) and prednisone (n = 48), CsA alone (n = 11), and CsA and methotrexate (n = 3). The median yield and purity of CD34+ cells after the procedure was 65% and 66% with Ceprate, and 48% and 86% with Isolex, respectively. The median number of CD34+ cells infused into the patients was 3.5 x 10(6)/kg (range 1-9.6). The median number of CD3+ cells administered was 0.4 x 10(6)/kg (range 0.01-2) using Ceprate and 0.14 x 10(6)/kg (range 0.03-2.5) using Isolex. Neutrophil recovery >500 and >1000/microl was achieved at a median of 13 days (range 8-22) and 14 days (range 9-31), respectively. Platelets recovered to >20,000 and >50,000/microl at a median of 13 days (range 0-128) and 18 days (range 0-180), respectively. The actuarial probability of acute GVHD II-IV was 10% (95% CI, 1-19%), and of extensive chronic GVHD 12% (95% CI, 11-13%).

Adolescent↗