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Biomedical subjects

G Masera

Publications and source records attributed to G Masera.

At least 109 records · Page 6Linked to original sources
PubMed1993

Childhood acute promyelocytic leukemia in Nicaragua.

BACKGROUND: The pediatric hematology-oncology service of the Managua 'La Mascota' Children's Hospital in Nicaragua began its activities in 1988. We report on unusual high incidence of acute promyelocytic leukemia (APL) observed in Nicaragua in the last three years. PATIENTS AND METHODS: From 1990 to 1992, 17 of 110 children with acute leukemia were diagnosed as having acute non-lymphoblastic leukemia (AnLL). The diagnosis was performed according to the FAB criteria. In two cases DNA was recovered for molecular analysis of the t(15; 17). RESULTS: Ten of 17 cases of AnLL were classified as APL. PML and RAR alpha gene rearrangements were observed in the two cases where molecular analysis was performed. Nine children received chemotherapy; one was treated with all-trans-retinoic acid (ATRA), achieving complete remission. Eight children who received chemotherapy died early of hemorrhage and/or sepsis. DISCUSSION: In Nicaragua, APL may be much more common than is generally observed elsewhere. In recent years initial treatment of APL with ATRA has proved to reduce the incidence of early hemorrhagic deaths, and complete remissions can be achieved without marrow aplasia and thus prevent infectious complications. From that perspective APL might become a curable disease, also in developing countries where the treatment of AnLL is not usually affordable.

Adolescent↗
PubMed1993

Atypical hereditary ovalocytosis associated with defective dyserythropoietic anemia.

The cases of a child and his mother affected by chronic anemia with atypical elliptocytosis are reported. When adolescent the mother underwent splenectomy, with an incomplete response. Anemia was characterized by a morphological picture of ovalocytosis associated with a significant percentage of spherocytes in the peripheral blood of the child and spiculated red cells in that of the splenectomized mother. Bone marrow aspirates of the child showed a striking erythropoietic hyperplasia with marked decrease of mature cells and dyserythropoietic features. Reticulocyte count was rather low. Ferrokinetics showed ineffective erythropoiesis. Biochemical studies on red blood cell membrane cytoskeleton showed that beta-spectrin, alpha-spectrin and protein 4.1, which are usually altered in hereditary elliptocytosis (HE), were normal in our cases. This report confirms the hypothesis of Torlontano who postulated the existence of a distinct atypical form of HE associated with ineffective and dysplastic erythropoiesis.

Anemia, Dyserythropoietic, Congenital↗
PubMed1993

Prospective comparative study of bone marrow transplantation and postremission chemotherapy for childhood acute myelogenous leukemia. The Associazione Italiana Ematologia ed Oncologia Pediatrica Cooperative Group.

PURPOSE: This study was conducted to assess the comparative values of allogeneic bone marrow transplantation (BMT) and autologous bone marrow transplantation (ABMT) with sequential postremission chemotherapy (SPC) in children with acute myelogenous leukemia (AML) in first remission. PATIENTS AND METHODS: From March 1987 to March 1990, 161 assessable patients younger than 15 years of age with newly diagnosed AML were treated uniformly with two courses of daunorubicin and standard-dose cytarabine. After initial consolidation with a course of daunorubicin, cytarabine, and thioguanine (DAT), patients in complete remission (CR) were randomized to receive either ABMT or SPC, except for those with an HLA-matched sibling who were assigned to undergo BMT. SPC consisted of three additional courses of DAT, followed by three pairs of drugs administered sequentially for a total of six cycles. RESULTS: Overall, 127 of 161 patients attained CR (79%). The estimated probabilities of survival and event-free survival (EFS) at 5 years for all patients were 42% and 25%, respectively (median follow-up, 28 months). For the 127 complete responders, the 5-year probability of disease-free survival (DFS) was 31%, with a cumulative risk of relapse of 64%. For the purpose of this study, all complete responders were evaluated for analysis of disease outcome according to the intent-to-treat principle, regardless of whether they actually received the intended therapy. The 5-year DFS was 51% for the BMT group (n = 24), significantly higher (P = .03) than that observed for the other cohorts: 21% for ABMT (n = 35), 27% for SPC (n = 37), and 34% for a group of 31 nonrandomized (NR) patients. Bone marrow relapse was the most frequent cause of postremission failure in all therapeutic subgroups, including the BMT cohort, in which no deaths attributable to the toxicity of the procedure were recorded. CONCLUSION: The results of this study show that BMT is more effective than ABMT or SPC in preventing leukemia relapse and extending DFS duration in children with AML in first remission.

Adolescent↗
PubMed1993

Hepatitis C virus infection and liver disease in children with thalassemia.

Antibody to the recently identified HCV and type of liver disease were investigated in 25 children with homozygous beta thalassemia. All patients were tested at regular intervals by second generation ORTHO-ELISA test. 19/25 (76%) patients were found repeatedly positive: in 11 cases seroconversion from anti-HCV- to anti-HCV+ status could be also documented. Liver disease was more severe in anti-HCV positive children. Seroconversion however did not produce major changes in liver disease outcome.

Adolescent↗
PubMed1993

Pulmonary thromboembolism in leukaemic children undergoing bone marrow transplantation.

Of 67 leukaemic children transplanted in our BMT unit 3 presented with severe acute respiratory syndrome associated with pulmonary thromboembolism (PTE) as diagnosed by scintiscan and/or angiography in the first month after BMT. Intervention with continuous positive pressure ventilation, urokinase (loading dose, then continuous infusion for 12-18 h) and heparin (continuous infusion for an average of 10 days) has been carried out successfully in two cases. In conclusion, when evaluating patients undergoing BMT and developing early pulmonary complications, PTE must be considered. The pathogenesis of PTE is still difficult to ascertain but urokinase therapy may reduce early morbidity.

Adolescent↗
PubMed1992

Isolated breast relapse after allogeneic bone marrow transplantation for childhood acute lymphoblastic leukemia.

Unusual sites of relapses following bone marrow transplantation (BMT) for childhood acute lymphoblastic leukemia (ALL) are rarely reported. We report the case of a 16-year-old girl who presented with an isolated right breast relapse 8 months after allogeneic BMT for ALL in second remission. Biopsy showed an ALL infiltrate. Bone marrow and CSF were normal. The girl never showed before extramedullary involvement. She was treated with local radiotherapy and mild systemic chemotherapy. Nine months after breast relapse, she presented an isolated central nervous system relapse. The treatment of isolated extramedullary relapses following BMT is still controversial.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

An unclassified case of congenital dyserythropoietic anaemia with a severe neonatal onset.

The case of a 13-year-old child with a congenital dyserythropoietic anaemia (CDA) is reported. A severe anaemia associated with a slight increase in reticulocytes, erythroblastosis, hyperbilirubinaemia, hepatosplenomegaly, generalized oedema and hypoproteinaemia was present at birth. Three exsanguino-transfusions were needed in the first 4 days of life. In the following years a continuous transfusional regimen was maintained in association with a chelating treatment. Bone marrow aspirates showed a striking hyperplasia of the erythroid lineage with ineffective erythropoiesis and changes of erythroblastic nuclei which were double but incompletely separated. Numerous histio-erythroblastic islands were also present. Electron microscopy studies did not show specific alterations of the erythropoietic cells. By a long-term evaluation of the clinical signs and of the haematological data, we came to the conclusion that the case does not fit into any of the three classical categories of CDA.

Adolescent↗
PubMed1992

Minimal residual disease in childhood acute lymphoblastic leukemia: analysis of patients in continuous complete remission or with consecutive relapse.

Differences in tumor cell burden among acute lymphoblastic leukemia (ALL) patients are largely unexplored, because methods of detecting residual malignant cells have not been sufficiently sensitive. Using the polymerase chain reaction (PCR) amplification of rearranged T-cell receptor delta(TCR delta)-chain junctional sequences for the preparation of clonospecific probes, we performed a retrospective PCR study of remission bone marrow (BM) samples in seven pediatric patients with ALL who subsequently relapsed (the largest series studied so far) and in 10 patients who were in longterm (greater than 39 to greater than 72 months) remission. Following two rounds of PCR primed by nested amplimers, 1 x 10(-4) to 1 x 10(-6) cells could be identified in 16 out of 17 cases. PCR analysis of 39 BM and peripheral blood samples obtained from ALL patients considered to be in complete remission according to morphological criteria revealed the following results. In BM remission specimens of all 10 patients in continuous complete remission for a long time (median 55 months), no residual leukemic cells could be identified in the latest remission sample available for PCR analysis. In three patients the persistence of residual leukemic cells, or the continuous increase of residual blasts to the point of clinical manifestation, were indicative of impending relapse. In three patients PCR analysis failed to identify residual leukemic cells in BM samples obtained 2, 6 and 16 months respectively before clinical relapse. Differences in the duration of minimal residual disease were not associated with distinct clinical-hematological features. In one patient a different pattern of V delta 2 recombination occurred in leukemic cells from diagnosis to relapse, thus preventing the further monitoring of the patient by the initial clonospecific probe.

Bone Marrow↗
PubMed1992

Central venous catheter-related complications after bone marrow transplantation in children with hematological malignancies.

We studied infectious and mechanical complications occurring with 55 central venous catheters (CVCs) managed in hospital and at home, in 53 children with hematological malignancies who underwent bone marrow transplantation (BMT). The total catheter life span was 6906 days (median 111), 2359 days (median 40) in hospital and 4547 days (median 78.5) at home. Duration of neutropenia was 1241 days (median 20), mostly in hospital. We observed 21 CVC-related infections from 17/55 CVCs (31%): 0.30 episodes/100 days of CVC use with 0.55/100 days in hospital vs 0.17/100 days at home. Antibiotic treatment resolved 72% of infections without CVC removal, which was required in six instances. There were 14 mechanical complications (0.20 episodes/100 days of CVC use) in 6/55 CVCs (11%), with three removals. Interventions to resolve mechanical problems included catheter declotting by urokinase, repair and replacement. We conclude that CVC is an essential component of care of children with cancer undergoing BMT and that it has a relatively low complication rate. Most complications can be resolved by an appropriate CVC handling and by a multidisciplinary intervention in the critical post-BMT phase.

Adolescent↗
PubMed1991

Hepatitis C virus infection and chronic liver disease in children with leukemia in long-term remission.

Antibody to the recently identified hepatitis C virus (HCV) was investigated in sera of 50 leukemic children who had chronic liver disease (CLD), observed for 1 to 12.6 years after therapy withdrawal. All patients were tested for anti-HCV at regular intervals: Ortho-enzyme-linked immunosorbent assay (ELISA) test was performed in all cases. Reactive sera were also tested by recombinant immunoblotting assay to define the specificity of the results obtained by ELISA. Twelve cases (24%) were persistently positive (group A), 11 (22%) were transiently anti-HCV+ positive (group B), and 27 (54%) were negative. Mean SGPT peak during follow-up was significantly higher in group A (P = .014, A v B and P less than .00001, A v C). SGPT normalized off-therapy in 1 of 12 cases (group A), 10 of 11 (group B), and 19 of 27 (group C) (P = .0004, A v B and P = .012, A v C). Accordingly, liver histology, available in 37 patients, showed signs of chronic hepatitis in all patients in group A while most patients in group B and C had less severe liver lesions. These results indicate that HCV plays a significant role in the etiology of chronic hepatitis in leukemic patients and that persistent anti-HCV activity correlates with a more severe CLD, which could jeopardize the final prognosis of children cured of leukemia.

Child↗
PubMed1991

Acute respiratory failure and pulmonary thrombosis in leukemic children.

Acute respiratory failure (ARF) in an 11-year-old child with pre-T acute lymphoblastic leukemia (ALL) at the beginning of induction therapy was observed, connected with a pulmonary thrombosis and not with an infective origin. A systematic search for this pathology identified six other children with the same pulmonary complication, five of whom where in the early phase of acute nonlymphoblastic leukemia (ANLL) and one in induction therapy for ALL in marrow relapse. At the beginning of the symptomatology, all children presented severe hypoxia and hypercapnia, with no or minimal chest radiograph abnormalities and no clear hemodynamic involvement. In all patients the arteriography and nuclear imaging studies confirmed the diagnosis. The causes of the thrombi could be connected with neoplastic emboli after cell lysis and/or with the vascular damage resulting from antiblastic therapy. Intravenous urokinase treatment and respiratory assistance had been successfully carried out in six of seven children.

Acute Disease↗
PubMed1991

Doxorubicin and m-AMSA induced DNA damage in blast cells from AML patients.

We investigated m-AMSA or doxorubicin (Dx) induced DNA single-strand breaks (DNA-SSB) in myeloid leukemia cells obtained from 8 adult patients suffering from AML. Highly purified AML cells were stimulated to proliferate with the addition of the appropriate growth factor (GCT) and exposed to different concentrations of m-AMSA or Dx for 1 or 4 h, respectively. DNA-SSB were determined by alkaline elution techniques. Either the kinetics or the amounts of DNA-SSB caused by both topoisomerase II inhibitors were variable among different cases. By increasing m-AMSA concentrations there was a concomitant increase in DNA-SSB up to a plateau at the highest concentrations. Dx induced DNA-SSB followed a bell shape curve with a decrease in the number of breaks at the highest concentrations that was evident in most cases. The interindividual variability of Dx-induced DNA-SSB was not correlated with intracellular Dx concentrations as assessed by flow cytometry. No correlation was evident between the amount of DNA breaks induced by m-AMSA and that induced by Dx. These data suggest that AML cells derived from different patients are not necessarily cross-sensitive or cross-resistant to topoisomerase II inhibitors with different chemical structures such as amsacrine or anthracyclines.

Adult↗
PubMed1991

Total parenteral nutrition and nutritional assessment and leukaemic children undergoing bone marrow transplantation.

The aggressive radiotherapy and chemotherapy used in conditioning regimens for children with leukaemia undergoing bone marrow transplantation (BMT) cause a severe catabolic state. Total parenteral nutrition (TPN) is indispensable in the management of these patients. 25 children with leukaemia undergoing BMT were studied to evaluate the efficacy of TPN and the value of anthropometric parameters and biochemical variables (albumin, retinol-binding protein and prealbumin) in monitoring nutritional status in the critical post-BMT phase. The complications of TPN were mainly metabolic, generally mild and easily controlled. The hyperalimentation solution and infusion line were not responsible for infection in any patient. The marked variations in anthropometric parameters and albumin expected in such patients were not observed in our children due to the nutritional support given. Prealbumin and retinol-binding protein showed statistically significant, positive variations (P less than 0.01), thus proving sensitive indices of the response to nutritional repletion.

Adolescent↗
PubMed1991

Allogeneic vs autologous BMT vs intensive chemotherapy in childhood AnLL during first complete remission: AIEOP experience. AIEOP Cooperative Group.

From 1982 to 1990, 340 children with newly diagnosed ANLL entered two consecutive AIEOP trials: LAM 8204 (1982-1987) and LAM 87 (1987-1990). Patients in both studies received identical remission induction with Daunorubicin and ARA-C. In the first study (LAM 8204) 167/171 patients were consolidated with four courses of DAT, followed by six additional courses of continuation therapy with three drug pairs given sequentially. Periodic intra-thecal ARA-C was used for CNS prophylaxis. For patients remaining on protocol, the OFS and EFS probability at 8 years was 35% and 30%, respectively. Induction response and EFS were adversely predicted by FAB MS subtype and hyperleukocytosis. In LAM 8204 trial there were 30 withdrawals represented by patients undergoing allogeneic (14) or autologous (16) BMT. For these patients the DFS probability at 5 years was 64% and 50%, respectively. On LAM-87 trial, 136/169 patients were evaluable and 98 (76%) attained CR. After consolidation with one course of DAT, patients with an HLA-identical donor underwent allogeneic BMT and those lacking a matched donor were randomized to receive either autologous BMT or the LAM 8204 postremission chemotherapy. The 2-year probability of DFS for allografted patients was 76% significantly higher (P = 0.0001) than that observed for patients on chemotherapy (12%) or autologous BMT (31%) arms.

Adolescent↗