Long-term follow-up of allogeneic marrow transplants in patients with aplastic anemia conditioned by cyclophosphamide combined with antithymocyte globulin.
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Adolescent↗
Biomedical subjects
J E Sanders
Publications and source records attributed to J E Sanders.
Marrow transplantation for chronic myeloid leukemia: the influence of plasma busulfan levels on the outcome of transplantation.
The influence of busulfan (BU) plasma concentration on outcome of transplantation from HLA identical family members for the treatment of chronic myelogenous leukemia (CML) was examined in 45 patients transplanted in chronic phase (CP) (n = 39) or accelerated phase (AP) (n = 6). All patients received the same regimen of BU, 16 mg/kg orally and cyclophosphamide (CY), 120 mg/kg intravenously. Plasma concentrations of BU at steady state (C(SS)BU) during the dosing interval were measured for each patient. The mean C(SS)BU was 917 ng/mL (range, 642 to 1,749; median, 917; standard deviation, 213). Of patients with C(SS)BU below the median, seven (five of 18 in CP and two of four in AP) developed persistent cytogenetic relapse and three of these patients died. There were no relapses in patients with C(SS)BU above the median. The difference in the cumulative incidence of relapse between the two groups was statistically significant (P = .0003). C(SS)BU was the only statistically significant determinant of relapse in univariable or multivariable analysis. The 3-year survival estimates were 0.82 and 0.64 for patients with C(SS)BU above and below the median (P = .33). There was no statistically significant association of C(SS)BU with survival or nonrelapse mortality, although the power to detect a difference in survival between 0.82 and 0.64 was only 0.24, similarly C(SS)BU above the median was not associated with an increased risk of severe regimen-related toxicity. We conclude that low BU plasma levels are associated with an increased risk of relapse.
Adult↗
Stem cell transplantation for secondary acute myeloid leukemia: evaluation of transplantation as initial therapy or following induction chemotherapy.
The purpose of this report is to describe the results of stem cell transplantation as initial treatment for secondary acute myeloid leukemia (AML). Forty-six patients (median age 42 years) with secondary AML (17 therapy-related, 29 myelodysplasia-related) who had not received remission induction chemotherapy underwent allogeneic (n = 43) or syngeneic (n = 3) transplantation. The 5-year actuarial disease-free survival was 24.4%, and the cumulative incidences of relapse and nonrelapse mortality were 31.3% and 44.3%, respectively. Lower peripheral blood blast count was associated with a lower risk of relapse (P = .05) and shorter time from AML diagnosis to transplant was associated with a lower risk of nonrelapse mortality (P = .02) and improved disease-free survival (P = .026). Patients with therapy-related secondary AML tended to have lower disease-free survival (P = .16) and a higher relapse rate (P = .16) than patients whose leukemia was not therapy-related. The results of these 46 previously untreated patients were compared to 20 patients (median age 36 years, 12 therapy-related, 8 myelodysplasia-related) transplanted with chemotherapy-sensitive disease after induction chemotherapy (first complete remission [n = 6], second complete remission [n = 3], first untreated relapse [n = 11]). We found no statistically significant difference in outcome between these 2 groups of patients. These results suggest that prompt transplantation should be considered after diagnosis of secondary AML or, if possible, high-risk myelodysplasia, particularly in patients with low peripheral blast counts. Innovative transplant strategies are needed to reduce the high risks of relapse and nonrelapse mortality seen in this patient population.
Adolescent↗
Bone marrow transplantation for pediatric malignancies.
Bone marrow transplantation is now being performed in children having a variety of hematologic malignancies and solid tumors. Marrow donors for patients with hematologic malignancies are usually allogeneic, including HLA-identical siblings, one-antigen mismatched family members, unrelated matched donors, or in some situations, two- or three-antigen mismatched family member donors. Umbilical cord blood is being explored as a source of hematopoietic reconstitution for some allogeneic transplants. Recipients with solid tumors most often receive autologous marrow or PBSC grafts. Posttransplant complications continue to include acute and chronic GVHD, infections, prolonged immunodeficiency, and recurrent malignancy. Because children are now surviving longer after transplantation, a variety of delayed effects are becoming apparent. These include, but may not be limited to, neuroendocrine dysfunction, neuropsychological effects, and ocular and pulmonary dysfunction. Secondary malignancies are now also becoming apparent, particularly among patients surviving more than 10 years after transplantation. Despite these known problems, marrow transplantation remains the treatment of choice for patients who relapse from conventional chemotherapy and for patients with CML in chronic phase and AML in first remission. Research continues to develop methods to decrease posttransplant complications and, hence, increase the probability of long-term disease-free survival.
Acute Disease↗
A bidirectional load applicator for the investigation of skin response to mechanical stress.
Instrumentation was developed to apply controlled biaxial (normal and shear) forces to the skin of a human or animal subject. The instrument mimicked any reference waveform within the constraints of a bandwidth of 15 Hz, a maximum force of 20 N, and displacement ranges of 15 mm for the normal direction and 18 mm for the shear direction. Two shaker motors, positioned with their axes parallel, were used with a low effective mass linkage and small-angle rotational joints to deliver the force. A digital feedback controller independently controlled the instantaneous normal and shear forces and recorded the resultant displacements. Evaluations on human and animal (pig) subjects demonstrated mean absolute errors between the applied and reference waveforms of less than 1.2% full-scale output for both the normal and shear directions. No degradation in performance was apparent over the course of a 1-h loading session. The instrument is to be used for the investigation of skin adaptation to mechanical stress, information that could be used to design new therapeutic methods to encourage skin load-tolerance.
Analog-Digital Conversion↗
Interface pressures and shear stresses at thirteen socket sites on two persons with transtibial amputation.
Residual limb/prosthetic socket interface pressures and shear stresses were measured at 13 sites on two subjects with unilateral transtibial amputation (TTA) using total-contact patellar-tendon-bearing prostheses. Maximal interface stresses during stance phase for each of 13 transducer sites were determined, then means for all steps calculated. Maximal pressure and resultant shear stress during stance phase were shown at anterior distal or mid-limb sites and the maxima occurred during the first 50% of stance phase. Anterior medial and lateral proximal sites showed their greatest pressure during the second 50%. At lateral mid-limb and popliteal fossa sites, resultant shear stress directions suggest that soft tissue was displaced toward the socket brim during weight-bearing. Results also suggest that skin across the distal tibial crest was in tension at the times of the first and second peaks in the shank axial force-time curve in all sessions. Significant difference (p < 0.05) in maximal stresses between sessions conducted > 3 weeks apart were apparent for both subjects.
Adult↗
Pubertal development of children treated with marrow transplantation before puberty.
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Adolescent↗
A modular six-directional force sensor for prosthetic assessment: a technical note.
A device designed to measure the forces and moments transmitted through prostheses of persons with lower limb amputation is presented. The sensing unit design is an advancement over previous prosthesis force measurement devices in that it is very thin (19 mm) and lightweight (527.5 g, including signal-conditioning instrumentation). The disk-shaped transducer fits between the socket and socket adapter of a standard modular prosthesis, measuring all six force and moment components at this location. Twelve strain gages were used, configured into six two-arm active Wheatstone bridge circuits. A 6X6 matrix was constructed from calibration data to relate the 6-component bridge-output vector to a 6-component force and moment vector. In a bench-test setting, the sensor was evaluated under typical load combinations encountered during the walking of a person with transtibial amputation (TTA) and shown to have errors less than 7.2% of the full-scale output for each direction. Data collected on a subject with TTA walking at different speeds are presented.
Amputation, Surgical↗
Pregnancies following high-dose cyclophosphamide with or without high-dose busulfan or total-body irradiation and bone marrow transplantation.
Patients successfully treated with a marrow transplant often have concerns about fertility and pregnancy. This study was performed to determine pregnancy outcome among patients who had received high-dose chemotherapy alone or with total-body irradiation (TBI) and marrow transplantation for aplastic anemia or hematologic malignancy. Records of 1,326 postpubertal and 196 prepubertal patients currently more than 12 years of age after marrow transplant in Seattle from August 1971 to January 1992 were reviewed to determine the patients with normal gonadal function and pregnancies. Among 708 postpubertal women, 110 recovered normal ovarian function and 32 became pregnant. In addition, nine formerly prepubertal girls with normal gonadal function became pregnant. Among 618 postpubertal men, 157 recovered testicular function and partners of 33 became pregnant. An additional two formerly prepubertal men had partners who became pregnant. Forty-one female patients and partners of 35 male patients had 146 pregnancies after transplant. All 76 patients responded to a questionnaire requesting pregnancy history, outcome, infant birth weight, and congenital anomalies information for all clinically recognized pregnancies. There were 115 live births among 146 (79%) pregnancies. Spontaneous abortion terminated four of 56 (7%) pregnancies for 28 female cyclophosphamide (CY) recipients and six of 16 (37%) pregnancies for 13 TBI recipients (P = .02). Partners of 28 male CY recipients had four of 62 (6.4%) pregnancies terminate with spontaneous abortion, but there were no spontaneous abortions among eight pregnancies of five TBI recipients' partners. Preterm delivery occurred for eight of 44 (18%) and five of eight (63%) live births for 24 CY and eight TBI female recipients (P = .01). This 25% incidence among all female patient pregnancies is higher than the expected incidence of 8% to 10% (P = .0001). The 13 preterm deliveries resulted in 10 low birth weight ([LBW] 1.8 to 2.24 kg) and three very low birth weight ([VLBW] < or = 1.36 kg) infants, for an overall incidence of 25%, which is higher than the expected incidence of 6.5% for the general population (P = .0001). Twelve of the 13 premature infants survive. Congenital anomalies were seen among two of 52 (3.8%) live-born infants of female and six of 63 (9.5%) live-born infants of male patients, which is not different from the 13% of single congenital anomalies reported for the general population. These data demonstrate that clinically recognized pregnancies among women who have received a marrow transplant incorporating TBI are likely to be accompanied by an increased risk of spontaneous abortion. Pregnancies among all women who received a marrow transplant are likely to be accompanied by preterm labor and delivery of LBW or VLBW babies who do not seem to be at an increased risk of congenital anomalies. However, determination of possible adverse effects of parental exposure to high-dose alkylating agents with or without TBI on children born posttransplant requires longer, additional follow-up.
Adult↗
Phase I trial of interleukin-2 after unmodified HLA-matched sibling bone marrow transplantation for children with acute leukemia.
Allogeneic bone marrow transplantation (BMT) for advanced acute leukemia is associated with a high risk of relapse. It is postulated that interleukin-2 (IL-2) administered after BMT might induce or amplify a graft-versus-leukemia effect and thereby reduce the relapse rate. To identify an IL-2 regimen for testing this hypothesis, a phase I trial of IL-2 (Roche) was performed in children in complete remission (CR) without active graft-versus-host disease (GVHD) off immunosuppressive agents after unmodified allogeneic matched-sibling BMT for acute leukemia beyond first remission. Beginning a median of 68 days after BMT, 17 patients received escalating doses of induction IL-2 (0.9, 3.0, or 6.0 x 10(6) IU/m2/d representing levels I, II, and III) for 5 days by continuous intravenous infusion (CIV). After 6 days of rest, they received maintenance IL-2 (0.9 x 10(6) IU/m2/d) for 10 days by CIV infusion. Levels I and II were well-tolerated, but, of 6 patients at level III, 1 developed pulmonary infiltrates, 1 developed hypotension (both resolved), and 1 died of bacterial sepsis and acute respiratory distress syndrome. Grade II acute GVHD developed in 1 patient at level I and 1 at level III. The maximum tolerated dose of induction IL-2 was level II. IL-2 induced lymphocytosis, with an increase in CD56+ and CD8+ cells. Ten patients remain in CR at 5+ to 67+ months. Thus, a regimen of IL-2 has been identified that did not induce a high incidence of acute GVHD when administered to children after unmodified allogeneic BMT. Its clinical activity will be assessed in a phase II trial.
Acute Disease↗
Allogeneic marrow transplantation for refractory anemia: a comparison of two preparative regimens and analysis of prognostic factors.
From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3-year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data.
Actuarial Analysis↗
Allogeneic marrow transplantation for aplastic anaemia associated with dyskeratosis congenita.
Eight patients with aplastic anaemia associated with dyskeratosis congenita received allogeneic marrow grafts from either HLA-identical siblings (six patients) or HLA-matched unrelated donors (two patients). Patients who received marrow from HLA-identical siblings were conditioned with cyclophosphamide (140-200 mg/kg), with or without antithymocyte globulin. Patients who received unrelated donor marrow were conditioned with cyclophosphamide (120 mg/kg) and total body irradiation (1200 cGy). The six patients who survived for >2 weeks following transplant all had haematological evidence of engraftment, and all three patients who survived for at least a year following transplant recovered normal haematological function. Three patients died with respiratory failure and pulmonary fibrosis at 70 d. 8 years and 20 years posttransplant; three patients died during the neutropenic period of invasive fungal infections; one patient died on day 44 of refractory acute graft-versus-host disease; and one patient remains alive 463 d following transplant. The surviving patient recently underwent surgical resection of a Dukes' stage C rectal carcinoma diagnosed 14 months posttransplant. The aplastic anaemia associated with dyskeratosis congenita can be successfully treated by allogeneic bone marrow transplantation; however, this approach does not reverse the other systemic manifestations of the syndrome. The pathogenesis of the intestinal lung disease observed in dyskeratosis congenita patients following marrow transplantation is not understood.
Adult↗
Unrelated donor marrow transplantation for myelodysplasia (MDS) and MDS-related acute myeloid leukaemia.
Allogeneic marrow transplantation using related marrow donors for myelodysplasia (MDS) and acute myeloid leukaemia (AML) arising from MDS results in 35-56% actuarial disease-free survival. Because the use of unrelated donors has not been well-characterized, we report on the outcome of 52 patients with MDS or MDS-related AML consecutively treated between 1987 and 1993 with unrelated donor marrow transplantation. The median age was 33 (range 1-53) years. 33 patients received chemotherapy and total body irradiation and the remainder busulfan and cyclophosphamide. The donors were phenotypically identical at the HLA-A, B and Dw/DRB1 loci in 34 cases and mismatched for one HLA locus in 17 cases and two loci in one case. Marrow was non-T-cell depleted and methotrexate with cyclosporine or FK506 was used for postgrafting immunosuppression. The 2-year disease-free survival, relapse, and non-relapse mortality rates were 38%, 28% and 48%, respectively. One patient who relapsed survives disease-free after withdrawal of immunosuppressive therapy. 16/19 survivors have a performance status of 90-100%. Patients with MDS in transformation or with AML had a significantly higher risk of relapse than patients with less advanced disease (P = 0.0014). Increased non-relapse mortality was significantly associated with higher age, longer disease duration before transplant, lower neutrophil count on admission and, unexpectedly, being seronegative for cytomegalovirus. We conclude that the outcome with transplantation using unrelated donors is similar to reported results using related donors and that a meaningful proportion of eligible patients with an otherwise incurable disease may be cured with this treatment. However, mortality from the transplant procedure is high and future studies should focus on reducing toxicity.
Acute Disease↗
Automated hexahedral mesh generation from biomedical image data: applications in limb prosthetics.
A general method to generate hexahedral meshes for finite element analysis of residual limbs and similar biomedical geometries is presented. The method utilizes skeleton-based subdivision of cross-sectional domains to produce simple subdomains in which structured meshes are easily generated. Application to a below-knee residual limb and external prosthetic socket is described. The residual limb was modeled as consisting of bones, soft tissue, and skin. The prosthetic socket model comprised a socket wall with an inner liner. The geometries of these structures were defined using axial cross-sectional contour data from X-ray computed tomography, optical scanning, and mechanical surface digitization. A tubular surface representation, using B-splines to define the directrix and generator, is shown to be convenient for definition of the structure geometries. Conversion of cross-sectional data to the compact tubular surface representation is direct, and the analytical representation simplifies geometric querying and numerical optimization within the mesh generation algorithms. The element meshes remain geometrically accurate since boundary nodes are constrained to lie on the tubular surfaces. Several element meshes of increasing mesh density were generated for two residual limbs and prosthetic sockets. Convergence testing demonstrated that approximately 19 elements are required along a circumference of the residual limb surface for a simple linear elastic model. A model with the fibula absent compared with the same geometry with the fibula present showed differences suggesting higher distal stresses in the absence of the fibula. Automated hexahedral mesh generation algorithms for sliced data represent an advancement in prosthetic stress analysis since they allow rapid modeling of any given residual limb and optimization of mesh parameters.
Artificial Limbs↗
Interface mechanics in lower-limb external prosthetics: a review of finite element models.
The distribution of mechanical stress at the interface between a residual limb and prosthetic socket is an important design consideration in lower-limb prosthetics. Stresses must be distributed so that the amputee is stable and comfortable, while avoiding trauma to the tissues of the residual limb. Numerical estimation of the stresses at the interface through finite element (FE) modeling can potentially provide researchers and prosthetists with a tool to aid in the design of the prosthetic socket. This review addresses FE modeling of interface stresses in lower-limb external prosthetics. The modeling methodologies adopted by analysts are described. Verification of FE estimates of interface stress against experimental data by different analysts is presented and the likely sources of error discussed. While the performance of the models is encouraging, there are definite limitations to all of them, necessitating further improvements. Parametric analysis of the sensitivity of interface stress to model parameters provides a tool to identify model weaknesses and to suggest possible refinements. Parametric analyses by different analysts are also presented and potential refinements discussed. Finally, directions for future work in prosthetic FE modeling are suggested.
Amputees↗
Phase II study of high-dose busulfan, melphalan and thiotepa with autologous peripheral blood stem cell support in patients with malignant disease.
The purpose of this study was to determine the toxicities and potential effectiveness of high-dose busulfan, melphalan and thiotepa (Bu/Mel/TT) followed by autologous peripheral blood stem cell (PBSC) infusion in patients with a variety of diseases. A phase II clinical trial of Bu (12 mg/kg), Mel (100 mg/m2) and TT (500 mg/m2) followed by PBSC infusion in 104 patients with breast cancer (n = 48), malignant lymphoma (n = 25), ovarian cancer (n = 13), multiple myeloma (n = 7) and other malignancies (n = 11) was performed. Sixty-two patients were treated in an academic medical center and 42 in a community cancer center. Grade 3-4 regimen-related toxicities occurred in 14% of patients, causing regimen-related mortality in six (6%) patients with an overall transplant-related mortality of 9%. Transplant-related deaths occurred in 6/62 patients (10%) treated in an academic medical center and in 3/42 (7%) treated in a community cancer center. Complete remissions (CR) were achieved in 1/17 (6%) patients with refractory stage IV breast cancer, 4/4 patients with responsive stage IV breast cancer, 6/13 (46%) with more-advanced lymphoma and 4/4 with less-advanced lymphoma. These patients are alive and disease-free a median of 712, 279, 461 and 404 days after transplant, respectively. Nineteen of 22 patients with stage II-III breast cancer remain alive and disease-free a median of 365 days after transplant. Complete remissions were also seen in 4/9 patients with ovarian cancer and 3/7 with multiple myeloma. The Bu/Mel/TT regimen followed by autologous PBSC infusion is associated with acceptable morbidity and mortality, appears to have significant activity in patients with breast cancer and is well tolerated in the adjuvant setting of stage II-III breast cancer. Bu/Mel/TT also appears to have significant activity in patients with lymphoma, multiple myeloma and possibly ovarian cancer. Further phase II-III studies are warranted in patients with these and other malignancies.
Adolescent↗
High-dose fractionated total-body irradiation, etoposide and cyclophosphamide for treatment of malignant lymphoma: comparison of autologous bone marrow and peripheral blood stem cells.
Consecutive patients with non-Hodgkin's lymphoma (NHL, n = 133) or Hodgkin's disease (HD, n = 20) were treated with 12.0 Gy of fractionated total body irradiation, etoposide 60 mg/kg, and CY 100 mg/kg followed by infusion of autologous hematopoietic stem cells. Seventy-nine patients received purged (n = 62) or unpurged BM (n = 17), and 74 received unpurged PBSCs alone (n = 56) or with BM (n = 18). The median day for achieving a sustained granulocyte count of 0.5 x 10(9)/I was 14 range (7-66) for BM recipients and 10 (7-30) for PBSC +/- BM recipients (P = 0.03). A platelet count of 20 x 10(9)/I was achieved at a median of day 24 (6-145) in BM recipients and day 11 (range, 7-56) in PBSC +/- BM recipients (P = 0.007). The median number of platelet units transfused was 86 (0-1432) for BM recipients and 30 (6-786) for PBSC +/- BM recipients (P = 0.001). The median number of hospital days was 36 (10-88) for BM recipients and 27 (14-76) for PBSC +/- BM recipients (P = 0.0001). The unadjusted Kaplan-Meier (KM) estimates of survival, event-free survival (EFS) and relapse at 2 years were 0.57, 0.45 and 0.43 for patients receiving BM and 0.55, 0.36 and 0.59 for patients receiving PBSC +/- BM. After adjusting for confounding variables, the estimated relative risk (RR) of death from any cause was 0.92 (P = 0.75), of relapse was 1.25 (P = 0.39), of non-relapse mortality was 0.71 (P = 0.42) and of mortality and/or relapse was 1.17 (P = 0.48) for patients receiving PBSC +/- BM as compared to BM. For 46 patients with NHL receiving unpurged PBSC alone, the unadjusted KM estimate of relapse was 0.61 compared with 0.48 for 52 comparable patients receiving purged BM, while the RR for relapse for patients receiving unpurged PBSCs was 1.37 (P = 0.33) after adjusting for other significant covariates. These data confirm previous observations that patients who receive PBSC +/- BM have faster engraftment, fewer transfusions and shorter hospital stays than patients who receive only BM. There were no statistically significant differences between the two groups in survival, relapse, death from causes other than relapse and event-free survival.
Adolescent↗
A controlled trial of long-term administration of intravenous immunoglobulin to prevent late infection and chronic graft-vs.-host disease after marrow transplantation: clinical outcome and effect on subsequent immune recovery.
To determine whether intravenous immunoglobulin (IVIg) given monthly from day 90 to day 360 posttransplantation decreased the incidence of late infection, chronic graft-vs.-host disease (GVHD), and obliterative bronchiolitis after marrow transplantation, patients were assigned randomly to receive either IVIg (500 mg/kg/month) or no IVIg prophylaxis. Participants were registered before transplantation, and 250 patients (123 IVIg and 127 control) were evaluable for events after day 100. The two groups were balanced for age, marrow source, cytomegalovirus (CMV) seropositivity, pretransplantation conditioning, and prophylaxis for infection and GVHD. Between days 100 and 365 posttransplantation, the incidence of bacteremia or septicemia per 100 patient-days of risk was 0.10 in the IVIg group and 0.12 in the controls (p = not significant). During the same period, the incidence of localized infection was marginally higher in control patients than in IVIg recipients (0.44 vs. 0.24, respectively; relative risk [RR] 1.46, p < 0.07). Administration of IVIg prophylaxis had no effect on survival, the incidence of obliterative bronchiolitis, severity of airflow obstruction, or the incidence or mortality of chronic GVHD. After discontinuing IVIg prophylaxis at day 360, subsequent recovery of endogeneous humoral immunity was impaired (serum IgG1 and IgA levels were significantly lower than controls at day 730), and total infections were less common in the second year in control patients than in former IVIg recipients (0.12 vs 0.19, respectively; RR 0.61, p = 0.03). We conclude that in the absence of hypogammaglobulinemia, monthly administration of IVIg given from day 90 to 360 does not reduce late complications and may impair long-term humoral immune recovery after marrow transplantation.
Adolescent↗