Biomedical subjects

N Bunin

Publications and source records attributed to N Bunin.

At least 19 recordsLinked to original sources

PubMed2006

Daclizumab for children with corticosteroid refractory graft-versus-host disease.

Daclizumab, a humanized IL-2 receptor antagonist, has been found to be safe and effective in adults with refractory graft-versus-host disease (GVHD); however, data describing its efficacy for refractory GVHD in children are limited. We report a series of 14 children who were treated with daclizumab for severe acute and/or chronic corticosteroid refractory GVHD. Patients were treated with 2 mg/kg weekly for 8 weeks followed by 1 mg/kg weekly for 4 weeks. Nine of 14 patients responded to daclizumab as measured by improvement of GVHD symptoms, and the ability to substantially wean corticosteroid dose. Five of 11 patients with acute GVHD had complete symptom resolution, and 2/11 had a partial response. Two of four patients with chronic GVHD had complete symptom resolution. In these patients, daclizumab was only effective in treating skin GVHD. Seven of the nine patients who had a complete or partial response eventually had recurrence of GVHD; however, the GVHD was less severe and no longer corticosteroid refractory. There was no infusional toxicity, and no infections that could be attributable to the drug. Daclizumab is a relatively safe and effective medication for corticosteroid refractory GVHD in children and larger studies are needed to evaluate its role in treatment.

Acute Disease↗

PubMed2006

Unrelated donor or partially matched related donor peripheral stem cell transplant with CD34+ selection and CD3+ addback for pediatric patients with leukemias.

Unmodified peripheral stem cell transplants are associated with an increased risk of extensive chronic GVHD. T depletion may reduce this risk, but the risk of graft failure or relapse may increase. To decrease the risks of both extensive chronic GVHD and graft failure, we added back a defined dose of CD3+ cells to CD34+ selected PSCs. Twenty-four patients were evaluable for outcome analysis. Donors were unrelated (23) or related (1). Conditioning was thiotepa, cyclophosphamide, and total body irradiation. Cyclosporine was used post transplant. Following CD34+ selection, a total of 5 x 10(5)/kg CD3+ cells were infused. Donors were matched for 12 patients. The median CD34+ dose infused was 7.1 x 10(6)/kg. Engraftment occurred in all patients at a median of 14 days (10-19). Twelve patients are alive in remission 15-34 months (median, 25) post PSCT. GVHD occurred in 17 patients, but was >grade II in only 2. Chronic GVHD occurred in 61.5% of evaluable patients, but was limited to skin and perioral cavity. Two patients relapsed, and 10 patients died of non-relapse causes. This study demonstrates that PSCT with CD34+ selection and a defined dose of CD3+ results in prompt engraftment and may limit development of extensive chronic GVHD.

Adolescent↗

PubMed2005

Outcomes of transplantation with partial T-cell depletion of matched or mismatched unrelated or partially matched related donor bone marrow in children and adolescents with leukemias.

Graft-versus-host disease (GVHD) remains a major barrier to successful hematopoietic stem cell transplant for patients who lack a matched related donor. Partial T-cell depletion (TCD) of the graft may decrease the risk of severe GVHD with unrelated donors (URD) and partially matched related donors (PMRD) while retaining an antileukemic effect. We analyzed our experience using URD and PMRD for pediatric patients with leukemias from 1990 to 2001. A subgroup of 'matched' URD donor pairs was retrospectively analyzed for high-resolution class I. Partial TCD was accomplished with monoclonal antibody T10B9 or OKT3 and complement. There were 76 URD (45% matched) and 28 PMRD recipients. Event-free survival (EFS) was 38.3%, and overall survival (OS) 45.1% at 3 years. On multivariate analysis, there was no difference in survival based upon marrow source, but nonrelapse mortality was higher with the use of PMRD. Relapse occurred in 6% of ALL patients, and 22.8% of AML/MDS patients. Grades III-IV GVHD was observed in only 6.7% of patients. Partial TCD allows use of matched or mismatched URD, or PMRD with little mortality from GVHD, durable engraftment, and no increase in relapse risk.

Adolescent↗

PubMed2005

Unrelated donor bone marrow transplantation for children with severe aplastic anemia: minimal GVHD and durable engraftment with partial T cell depletion.

Both increased graft rejection and increased graft vs host disease (GVHD) remain obstacles to success for unrelated donor (URD) BMT for patients with SAA. Partial T cell depletion (PTCD) may decrease the risk of severe GVHD, while still maintaining sufficient donor T lymphocytes to ensure engraftment. We report on 12 patients with SAA who underwent PTCD URD BMT. All patients had failed medical therapy or relapsed following initial responses, and were transfusion dependent. The median age was 6 years, and there were five males. Donors were matched for four patients, and mismatched for eight. All patients received total body irradiation with either Ara-C or thiotepa and cyclophosphamide. PTCD was accomplished using monoclonal antibody T10B9 or OKT3 and complement. All patients engrafted, with a median time of 18 days to ANC >500. Only one patient had greater than grade II acute GVHD; two patients had limited and one patient extensive chronic GVHD. Nine patients are alive and transfusion independent at a median months post BMT. Three patients died from infection or renal failure. This series suggests that an aggressive immunosuppressive conditioning regimen with PTCD results in successful engraftment and minimal GVHD in pediatric patients with SAA, even with HLA mismatched donors.

Adolescent↗

PubMed2004

Pulmonary infection with microsporidia after allogeneic bone marrow transplantation.

Microsporidia are obligate, intracellular protozoal parasites that can be pathogenic in immunocompromised individuals. The majority of cases of microsporidiosis have been documented in patients with HIV, and only a few case reports exist of infection in solid organ transplant patients. We report the first case of pulmonary microsporidial infection in an allogeneic bone marrow transplant recipient in the US. The patient was a recipient of a T-cell-depleted graft who succumbed to complications from respiratory failure 63 days post transplant. The diagnosis was made post mortem by electron microscopy and confirmed with PCR. Although rare, microsporidial infection should be considered in the differential diagnosis of unexplained pulmonary infection in bone marrow transplant patients.

Adult↗

PubMed2003

Randomized trial of busulfan vs total body irradiation containing conditioning regimens for children with acute lymphoblastic leukemia: a Pediatric Blood and Marrow Transplant Consortium study.

Conditioning regimens for children with ALL have generally included total body irradiation (TBI), which may result in significant sequelae. The primary aim of this study was to evaluate the outcome for children with ALL undergoing allogeneic stem cell transplant (SCT) with either busulfan (Bu) or TBI regimens. Patients <21 years with ALL undergoing allogeneic SCT were eligible. Conditioning included either Bu or TBI, with etoposide 40 mg/kg and cyclophosphamide 120 mg/kg. Randomization was stratified based upon duration of remission, remission status, and prior cranial irradiation. A total of 43 patients were enrolled; 21 received Bu and 22 TBI. Median patient age was 8 years (0.5-20 years). Remission status included 12 patients in CR1, 25 in CR2, and six in CR3. At a median follow-up of 43 months, event-free survival (EFS) is 45% at 3 years, with 29% EFS in the Bu arm and 58% in the TBI arm (P=0.03). There was no significant difference between Bu and TBI for patients who received stem cells from related donors (36 vs 58%, P=0.3). However, for URD, EFS was 20% for Bu and 57% for TBI (P=0.04). Relapses were similar in both arms. This randomized prospective study suggests that Bu is inferior to TBI for pediatric patients with ALL undergoing allogeneic SCT.

Adolescent↗

PubMed2001

Cyclophosphamide-based, seven-drug hybrid and low-dose involved field radiation for the treatment of childhood and adolescent Hodgkin disease.

PURPOSE: The outlook for children and adolescents with Hodgkin disease (HD) is excellent with combined modality therapy. However, the long-term toxicities of multiagent therapy and radiation therapy remain of concern for these patients with curable disease. In an attempt to reduce long-term toxicities while preserving excellent cure rates, we developed a combined-modality protocol using a modified seven-drug hybrid and low-dose (2,000 cGy) involved field radiation therapy (RT). The hybrid used cumulative doses of alkylating agents and anthracyclines that were lower than those used in previous four-drug regimens and substituted a less leukemogenic agent, cyclophosphamide, for nitrogen mustard. PATIENTS AND METHODS: From 1991 through 1994 a cyclophosphamide, vincristine, procarbazine, and prednisone/adriamycin, bleomycin, and vinblastine hybrid was used to treat 29 patients with HD. Median age was 12 years (range 6-16 yrs). Patients who were postpubertal with early stage disease as determined by surgical staging were excluded. Treatment consisted of four cycles of therapy for stages I and IIA, six cycles for stages IIB and III, and eight cycles for stage IV. Twenty-two patients also received low-dose RT to areas of bulky disease. RESULTS: Twenty-eight patients (97%) had a complete response to chemotherapy. Five patients experienced relapse; two died from disease 27 and 29 months after initial diagnosis; three received additional therapy and are alive with no evidence of disease. Follow-up for all other patients is a median of 56 months (range 24-78 mos) from cessation of therapy and all have remained disease-free. At 5 years follow-up, actuarial disease-free survival is 82%, and the overall survival is 93%. There have been no clinically significant cardiac or pulmonary toxicities and no secondary malignancies. CONCLUSIONS: This therapy has resulted in 5-year overall survival and disease-free survival rates similar to regimens using higher doses of alkylating agents, anthracyclines, and radiation. Longer follow-up will be necessary to fully evaluate disease-free survival, organ damage, and quality of life.

Adolescent↗

PubMed2000

Impact of bone marrow transplantation for symptomatic sickle cell disease: an interim report. Multicenter investigation of bone marrow transplantation for sickle cell disease.

Fifty children who had symptomatic sickle cell disease received matched sibling marrow allografts between September 1991 and March 1999, with Kaplan-Meier probabilities of survival and event-free survival of 94% and 84%, respectively. Twenty-six patients (16 male, 10 female) had at least 2 years of follow-up after transplantation and were evaluated for late effects of transplantation and for its impact on sickle cell-related central nervous system (CNS) and pulmonary disease. Patients ranged between 3.3 and 14.0 (median, 9. 4) years of age and had a median follow-up of 57.9 (range 38-95) months after transplantation. Among 22 of 26 patients who had stable donor engraftment, complications related to sickle cell disease resolved, and none experienced further episodes of pain, stroke, or acute chest syndrome. All 10 engrafted patients with a prior history of stroke had stable or improved cerebral magnetic resonance imaging results. Pulmonary function tests were stable in 22 of the 26 patients, worse in two, and not studied in two. Seven of eight patients transplanted for recurrent acute chest syndrome had stable pulmonary function. Linear growth measured by median height standard deviation score improved from -0.7 before transplantation to -0.2 after transplantation. An adverse effect of busulfan conditioning on ovarian function was demonstrated in five of seven evaluable females who are currently at least 13 years of age. None of the four males tested had elevated serum gonadotropin levels. These data confirm that allogenic bone marrow transplantation establishes normal erythropoiesis and is associated with improved growth and stable CNS imaging and pulmonary function in most patients. (Blood. 2000;95:1918-1924)

Adolescent↗

PubMed2000

Rapid-sequence tandem transplant for children with high-risk neuroblastoma.

BACKGROUND: The majority of patients with high risk neuroblastoma (NB) still relapse. PROCEDURE: We designed a Phase II trial for children with advanced NB utilizing a program of induction chemotherapy followed by tandem high-dose chemoradiotherapy with stem cell rescue (HDC/SCR) in rapid sequence. Fifty-five patients were evaluable, ages 1-14 years, and 97 cycles of HDC/SCR have been completed to date. Pheresis was possible for every patient, despite their young age, with an average of 7.2 x 10(6) CD34+ cells/kg available to support each HDC/SCR cycle. RESULTS: Engraftment was rapid, with median time to neutrophil engraftment of 11 days. Five patients who completed the first HDC course did not complete the second and there were four toxic deaths. With a median follow-up of 24 months from diagnosis, 38 of 55 patients (3-year EFS 59%) remain event-free. A subset of the patients received stem cells purged by CD34 selection. The engraftment and EFS of these patients are similar to the overall group. CONCLUSION: This work demonstrates that a tandem transplant regimen for high-risk NB is a feasible treatment strategy in children and may improve disease-free survival.

Adolescent↗

PubMed2000

Longitudinal evaluation of cardiopulmonary performance during exercise after bone marrow transplantation in children.

OBJECTIVE: Abnormalities in cardiopulmonary performance during exercise have been reported in children after bone marrow transplantation (BMT). We sought to study changes in exercise performance over time in pediatric BMT survivors. STUDY DESIGN: We retrospectively reviewed the results of serial cardiopulmonary exercise tests performed by patients who had undergone BMT at our institution. Four measurements of cardiopulmonary function are reported: maximum cardiac index (MCI), maximal oxygen consumption (Max VO(2)), oxygen consumption at ventilatory threshold (VO(2) at VT), and maximum work (Max Work) performed. A linear mixed-effects model was fitted to assess changes in these parameters over time. RESULTS: Thirty-three patients performed 96 cardiopulmonary exercise tests. MCI and VO(2) at VT were depressed at initial testing and did not change over time. Max VO(2) increased by 4% per year to 69% predicted, and Max Work increased to 77% predicted at 6 years after BMT. CONCLUSIONS: In spite of an impaired cardiovascular response to exercise as indicated by the persistently low MCI, aerobic and physical working capacity increase. Improved Max VO(2) suggests that oxygen extraction at the musculoskeletal level becomes more efficient with recovery from BMT. This may represent a compensatory response to an impaired ability to increase cardiac output.

Adolescent↗

PubMed2000

Tandem high-dose therapy in rapid sequence for children with high-risk neuroblastoma.

PURPOSE: Advances in chemotherapy and supportive care have slowly improved survival rates for patients with high-risk neuroblastoma. The focus of many of these chemotherapeutic advances has been dose intensification. In this phase II trial involving children with advanced neuroblastoma, we used a program of induction chemotherapy followed by tandem high-dose, myeloablative treatments (high-dose therapy) with stem-cell rescue (HDT/SCR) in rapid sequence. PATIENTS AND METHODS: Patients underwent induction chemotherapy during which peripheral-blood stem and progenitor cells were collected and local control measures undertaken. Patients then received tandem courses of HDT/SCR, 4 to 6 weeks apart. Thirty-nine patients (age 1 to 12 years) were assessable, and 70 cycles of HDT/SCR were completed. RESULTS: Pheresis was possible in the case of all patients, despite their young ages, with an average of 7.2 x 10(6) CD34(+) cells/kg available to support each cycle. Engraftment was rapid; median time to neutrophil engraftment was 11 days. Four patients who completed the first HDT course did not complete the second, and there were three deaths due to toxicity. With a median follow-up of 22 months (from diagnosis), 26 of 39 patients remained event-free. The 3-year event-free survival rate for these patients was 58%. CONCLUSION: A tandem HDT/SCR regimen for high-risk neuroblastoma is a feasible treatment strategy for children and may improve disease-free survival.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1998

Neuropsychological outcome of children undergoing bone marrow transplantation.

The purpose of the study was to prospectively evaluate the neuropsychological functioning of children and adolescents receiving a bone marrow transplant (BMT). One hundred and twenty-two children with malignant or nonmalignant disorders and no previous cranial radiation therapy received a pre-BMT neuropsychological evaluation. Surviving children received a 1 year post-BMT neuropsychological evaluation. Patients were placed in a chemotherapy only (chemo) or a chemotherapy and total body irradiation (chemo + TBI) group for statistical analysis. The data were analyzed by t-tests for paired samples. There were no statistically significant differences. Regression analysis failed to identify treatment, age and gender effects. The results suggest that global and specific areas of neuropsychological functioning 1 year post-BMT were not detrimentally affected by chemotherapy or chemotherapy with total body irradiation.

Adolescent↗

PubMed1997

Collaborative multicenter investigation of marrow transplantation for sickle cell disease: current results and future directions.

We present updated results of a multicenter collaborative investigation of bone marrow transplantation for sickle cell disease. Between September 1991 and April 1997, thirty-four children less than 16 years of age with severe sickle cell disease received marrow allografts from HLA-identical siblings. Indications for transplantation included a history of stroke (n = 17), recurrent acute chest syndrome or sickle pulmonary disease (n = 10), and recurrent vaso-occlusive crises (n = 7). Twenty-one patients received regular red blood cell (RBC) transfusions to prevent complications of sickle cell disease. Patients were prepared for transplantation with busulfan, cyclophosphamide, and antithymocyte globulin or CAMPATH (Cambridge Pathology) antibody. Thirty-two of the 34 patients survived, with a median follow-up of 26.5 months (range, 0.2-66.9 months); and 28 patients demonstrated stable engraftment of donor hematopoietic cells. Graft rejection or recurrence of sickle cell disease occurred in four patients, and two patients died of intracranial hemorrhage or graft-vs.-host disease. In the group of 34 children with symptoms of advanced sickle cell disease, current Kaplan-Meier estimates of survival and event-free survival are 93% and 79%, respectively.

Adolescent↗

PubMed1996

Identification of human juvenile chronic myelogenous leukemia stem cells capable of initiating the disease in primary and secondary SCID mice.

Most juvenile chronic myelogenous leukemia (JCML) cells have limited long-term proliferative capacity, and only a minority of immature cells give rise to colonies in semisolid cultures. Clonogenic JCML progenitors cannot be maintained in culture because they differentiate, and within a few weeks the leukemic clone is lost. This makes it difficult to identify the cell that initiates and maintains the disease in patients. To determine the proliferative capacity of JCML cells in vivo, bone marrow (BM), peripheral blood, or spleen cells from eight patients with JCML either at diagnosis or during treatment were transplanted into sublethally irradiated severe combined immune deficient (SCID) mice. JCML cells from all patients homed to the murine BM and proliferated extensively in response to exogenous stimulation with granulocyte-macrophage colony-stimulating factor. Within a few weeks, highly engrafted mice became ill and cachectic due to infiltration of leukemic cells and secretion of tumor necrosis factor-alpha. Murine BM, spleen, and liver were infiltrated with leukemic blasts, and typical JCML colony-forming progenitors could be recovered. Kinetic experiments demonstrated that only a small minority of transplanted cells homed to the murine BM, and that these cells initiated and maintained the disease in vivo by extensive proliferation and differentiation. To characterize the cell-surface phenotype of the JCML initiating cell (JCML-IC), JCML blood or spleen cells were fractionated on the basis of CD34/CD38 marker expression and transplanted into SCID mice. Only immature CD34+ cells could initiate the disease, while mature CD34- cells did not engraft. Within the CD34+ compartment, there was enrichment for JCML-ICs by immature cells with a CD34+/CD38- stem-cell-like phenotype. Mice transplanted with more mature CD34+/CD38+ populations that also contained clonogenic JCML progenitors were poorly engrafted. These results indicate that the JCML-IC is an earlier stage of development than clonogenic JCML progenitors. Additional evidence that the JCML-IC has stem-cell properties comes from secondary transplant experiments that test the self-renewal capacity. The JCML-IC from all three patients tested could successfully reinitiate the disease in secondary murine recipients. Thus, we have developed a functional in vivo model that replicates many aspects of human JCML, and have used this model to identify and characterize JCML-ICs and their stem-cell properties.

Animals↗

PubMed1996

Outcome of unrelated donor bone marrow transplantation in 40 children with Hurler syndrome.

Long-term survival and improved neuropsychological function have occurred in selected children with Hurler syndrome (MPS I H) after successful engraftment with genotypically matched sibling bone marrow transplantation (BMT). However, because few children have HLA-identical siblings, the feasibility of unrelated donor (URD) BMT as a vehicle for adoptive enzyme therapy was evaluated in this retrospective study. Forty consecutive children (median, 1.7 years; range, 0.9 to 3.2 years) with MPS I H received high-dose chemotherapy with or without radiation followed by BMT between January 27, 1989 and May 13, 1994. Twenty-five of the 40 patients initially engrafted. An estimated 49% of patients are alive at 2 years, 63% alloengrafted and 37% autoengrafted. The probability of grade II to IV acute graft-versus-host disease (GVHD) was 30%, and the probability of extensive chronic GVHD was 18%. Eleven patients received a second URD BMT because of graft rejection or failure. Of the 20 survivors, 13 children have complete donor engraftment, two children have mixed chimeric grafts, and five children have autologous marrow recovery. The BM cell dose was correlated with both donor engraftment and survival. Thirteen of 27 evaluable patients were engrafted at 1 year following URD BMT. Neither T-lymphocyte depletion (TLD) of the bone marrow nor irradiation appeared to influence the likelihood of engraftment. Ten of 16 patients alive at 1 year who received a BM cell dose greater than or equal to 3.5 x 10(8) cells/kg engrafted, and 62% are estimated to be alive at 3 years. In contrast, only 3 of 11 patients receiving less than 3.5 x 10(8) cells/kg engrafted, and 24% are estimated to be alive at 3 years (P = .05). The mental developmental index (MDI) was assessed before BMT. Both baseline and post-BMT neuropsychological data were available for 11 engrafted survivors. Eight children with a baseline MDI greater than 70 have undergone URD BMT (median age, 1.5 years; range, 1.0 to 2.4 years). Of these, two children have had BMT too recently for developmental follow-up. Of the remaining six, none has shown any decline in age equivalent scores. Four children are acquiring skills at a pace equal to or slightly below their same age peers; two children have shown a plateau in learning or extreme slowing in their learning process. For children with a baseline MDI less than 70 (median age, 2.5 years; range, 0.9 to 2.9 years), post-BMT follow-up indicated that two children have shown deterioration in their developmental skills. The remaining three children are maintaining their skills and are adding to them at a highly variable rate. We conclude that MPS I H patients with a baseline MDI greater than 70 who are engrafted survivors following URD BMT can achieve a favorable long-term outcome and improved cognitive function. Future protocols must address the high risk of graft rejection or failure and the impact of GVHD in this patient population.

Bone Marrow Transplantation↗

PubMed1996

Related donor liver transplant for veno-occlusive disease following T-depleted unrelated donor bone marrow transplantation.

Veno-occlusive disease (VOD) is the third leading cause of mortality after bone marrow transplant. Management consists of supportive care, with restricted fluids and diuretics. Most patients will recover, but approximately 25% may develop severe life threatening VOD with subsequent respiratory compromise and multiorgan failure. Orthotopic liver transplant has been attempted for a few patients with intractable VOD, but this approach is limited by availability of a cadaveric organ. We report a child who underwent a T-depleted unrelated donor bone marrow transplant for severe aplastic anemia as a manifestation of Schwachman-Diamond syndrome who developed severe VOD. She had evidence of engraftment when liver transplant was considered, and had no evidence of major organ dysfunction. The left lateral segment of her mother's liver was transplanted at day +33 following bone marrow transplantation. The child remains well ten months post-BMT and nine months after liver transplant. A related donor liver transplant may be a justifiable approach in a patient with severe VOD post-BMT.

Bone Marrow Cells↗

PubMed1996

Juvenile chronic myelogenous leukemia multilineage CD34+ cells: aberrant growth and differentiation properties.

Juvenile chronic myelogenous leukemia (JCML) is a hematologic malignancy of monocyte-macrophage lineage in which leukemic progression is mediated in an autocrine manner by tumor necrosis factor (TNF-alpha), GM-CSF and possibly other growth factors. Cytogenetic data showing involvement of both erythroid and monocyte-macrophage lineages in the JCML leukemic clone, as well as an observed episode of B-lineage lymphoid blast crisis in JCML, has strengthened the thesis for a lympho-hematopoietic pluripotent stem cell origin for the disorder. To study this further, JCML CD34+ cells from bone marrow (BM) or spleen from six newly diagnosed patients were isolated and cultured in clonogenic assays with combinations of recombinant cytokines. Compared to control CD34+ cells, JCML cells from all patients showed an aberrant growth pattern restricted almost exclusively to the monocyte-macrophage lineage. Most of the clonogenic activity was seen in a subsorted population of CD34+, HLA-Dr- cells. Additionally, an exaggerated growth response to minute doses of GM-CSF that had no effect on control cells was observed with JCML CD34+ cells. Recloning ("self-renewal") of JCML CD34+ cells was also strongly promoted by GM-CSF. JCML colonies also formed spontaneously in the absence of exogenous cytokines but were augmented by GM-CSF, interleukin 1 and TNF-alpha, the latter feature not seen with control CD34+ cells from normal BM. The abnormal spontaneous growth pattern of CD34+ JCML cells could be suppressed directly in vitro by anti-TNF-alpha antibodies and anti-GM-CSF antibodies alone or in combination, and by soluble TNF-alpha receptors (sTNF-R:Fc), consistent with the notion that JCML CD34+ cells are stimulated by both cytokines in an autocrine manner. In malignant CD34+ cells from one patient, the cytogenetic marker monosomy 7 proved leukemic involvement of monocyte-macrophage, erythroid and B-lymphoid lineages. We conclude that CD34+ JCML cells of multilineage potential exhibit excessive and aberrant monocyte-macrophage colony formation, a property that was previously observed in JCML progenitors found in light density cell fractions. Thus, within the CD34+ cellular compartment is a subpopulation of JCML "stem" cells that accounts for the abnormal leukemic proliferative activity in this disease.

Adult↗

PubMed1996

Endodermal sinus tumor in children.

Malignant germ cell tumors account for about 3% of neoplasms in children, and endodermal sinus tumor (EST) is the most common histological subtype. The authors reviewed 22 years' experience (at their institution) in the management of 37 patients with this tumor. Fifteen of them (41%) had a sacrococcygeal primary, 10 had a testicular tumor (27%), 6 had an ovarian tumor (16%), 3 had a vaginal tumor (8%) and 3 had tumors at other sites (8%). Seven (19%) patients presented with metastatic disease, primarily pulmonary. The serum alpha-fetoprotein (AFP) level was elevated in all cases tested. The initial chemotherapy regimen included vincristine, actinomycin, cyclophosphamide (VAC), and Adriamycin (6 patients), but since 1985 the regimen has been changed to include cisplatin or Carboplatin, etoposide, and bleomycin (21 patients). Eight patients with testicular tumors initially were treated with surgical excision alone. Computed tomography results were a poor predictor of recurrence, but AFP surveillance was extremely sensitive. No second-look operation detected residual tumor in the absence of AFP elevation. Initial relapse for all patients tended to occur early (within 2 years), locally, and often with pulmonary metastases. Although historically the prognosis for patients with EST has been poor, the overall 2-year survival rate in this series was 70%. The best prognosis was among the children who had a testicular primary tumor (survival rate, 100%). The 2-year survival rate for patients with ovarian tumors was 67%; for those with sacrococcygeal primaries it was 60%. These results suggest that the prognosis for children with EST has improved significantly over the past decade. Contributing factors include therapy based on cisplatin, etoposide, and bleomycin, and relapse surveillance with serial AFP determinations. Second-look procedures should be reserved for patients who have an increasing level of serum AFP, suspicious computed tomography findings, and no obvious evidence of metastatic disease.

Adolescent↗