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C Vermylen

Publications and source records attributed to C Vermylen.

At least 37 records · Page 2Linked to original sources
PubMed1998

Primary and secondary osteosarcoma of the face: a rare childhood malignancy.

BACKGROUND: Osteosarcoma of the head and neck, especially primary forms, remains a rare and highly malignant tumor. PATIENTS: This report describes two patients who developed an osteosarcoma of the face more than ten years after treatment for bilateral retinoblastoma. We also report a third patient who presented with a primary osteosarcoma of the right superior maxilla which is one of the rarest tumors encountered in childhood oncology. CONCLUSIONS: The mainstay of therapy is surgical resection with negative margins. Careful, long-term follow-up of survivors of hereditary retinoblastoma is essential, especially for those given radiation therapy.

Adolescent↗
PubMed1998

Chronic relapsing thrombotic thrombocytopenic purpura: three case reports and update of the pathogenesis and therapeutic modalities.

Chronic relapsing thrombotic thrombocytopenic purpura (CRTTP) is the rarest type of TTP, usually presenting in childhood. The aetiology is still not fully explained. The disorder is associated with the presence in plasma of unusually large von Willebrand factor (UlvWF) multimers that are especially prominent between episodes. CRTTP can be prevented by periodic plasma transfusions. We report three children with congenital CRTTP who have been successfully treated and maintained in prolonged remission by the prophylactic use of fresh frozen plasma without concurrent plasmapheresis. Two of the patients are sibs.

Adult↗
PubMed1998

Haematopoietic stem cell transplantation for sickle cell anaemia: the first 50 patients transplanted in Belgium.

Fifty patients affected by sickle cell anaemia underwent transplantation of HLA-identical haematopoietic stem cells (bone marrow, 48; cord blood, 2). Two groups of patients were considered for transplantation. Group 1 included 36 permanent residents of a European country who, retrospectively, met the inclusion criteria accepted at a consensus conference held in Seattle in 1990, wherein children were selected because they already had evidence of a morbid course. Group 2 included 14 patients who were transplanted earlier, had not received more than three blood transfusions and were transplanted because they had decided to return to their country of origin. Kaplan-Meier estimates of overall survival, event-free survival and disease-free survival at 11 years of the whole grafted population are 93, 82 and 85%, respectively. In group 1, overall survival, EFS and DFS were 88, 76 and 80% and in group 2, 100, 93 and 93%, respectively. Clinical manifestations of the disease, as well as disease associated haemolytic anaemia, disappeared in all successfully treated patients. Recovery of spleen function was present in seven out of 10 evaluated patients. Adverse events (death, absence of engraftment, mixed chimerism and relapse) occurred more frequently in group 1 than in group 2 (25% vs 7%, P< 0.001). Acute graft-versus-host disease (GVHD) was present in 20 patients (grade I or II, 19; grade III, 1), chronic GVHD in 10 (limited, 7; extensive, 3). One patient developed an acute myeloid leukaemia. Gonadal dysfunction was present in all patients (six boys and eight girls) transplanted close to or after puberty, although transient in one adolescent girl.

Adolescent↗
PubMed1998

Allogeneic stem cell transplantation for Fanconi Anaemia. Severe Aplastic Anaemia Working Party of the EBMT and EUFAR. European Group for Blood and Marrow Transplantation.

Fanconi anaemia is a hereditary disorder characterised by chromosomal breaks increased by cross-linking agents. Bone marrow transplantation is the treatment of choice when a HLA identical sibling donor has been identified. The use of low-dose cyclophosphamide with thoraco-abdominal irradiation for the conditioning regimen of FA patients has lead to a dramatic improvement of survival, with a long-term survival of 75% at our institution. However, if most patients are completely cured of their haematological disease, there is concern about an increased frequency of secondary tumours, mostly head and neck squamous cell carcinomas of poor prognosis. Results of BMT using alternative donors (HLA mismatched related and unrelated donors) have also improved during the last decade. A better selection of the donor via high-resolution techniques for class-II HLA matching, and more recently the use of T cell depleted grafts are probably the main explanations. Despite a short follow-up and the small number of patients analysed, transplants using HLA matched family cord blood give some promising results. On the other hand, first results with unrelated cord blood remind that this approach is clearly an experimental one that has to be evaluated through international registries and prospective studies. New approaches including autologous stem cell transplantations and gene therapy are currently explored.

Fanconi Anemia↗
PubMed1997

Disseminated Mycobacterium avium infection in a child with decreased tumour necrosis factor production.

UNLABELLED: Disseminated atypical mycobacterium infection is essentially reported in cellular immunodeficient children. Cell-mediated immunity including cytokines like tumour necrosis factor alpha (TNF) and gamma interferon (IFN) is the most important factor allowing control of the dissemination of Mycobacterium. We report a child with disseminated Mycobacterium avium infection without classical immunodeficiency or HIV infection. Immunological studies revealed a defect of TNF production when the monocytes of the patient were primed with endotoxin (Escherichia coli). CONCLUSION: This patient represents a further case of possible macrophage defect explaining the susceptibility to intracellular pathogens.

Child, Preschool↗
PubMed1997

A prospective study of minimal residual disease in childhood B-lineage acute lymphoblastic leukaemia: MRD level at the end of induction is a strong predictive factor of relapse.

We prospectively investigated minimal residual disease (MRD) in 51 children with B-lineage acute lymphoblastic leukaemia (ALL) treated according to the Fralle 93 protocol. PCR follow-up was performed in children in morphological and cytogenetic complete remission, provided an immunoglobulin (IgH) gene rearrangement could be detected using FR 3/J(H) amplimers. MRD was studied according to our previously described methodology, with a few modifications including the use of a consensus J(H) probe to control for PCR efficiency variations. Out of the initial 51 patients, 34 were assessable for MRD at the end of induction at the time of analysis. MRD levels were as follows: > 1/10(3) in 26%, 1/10(3) to 1/10(4) in 50% and < 1/10(4) or not detectable in 24%. With a median follow-up of 20 months there were five relapses, all of which occurred in the group of patients with MRD > 1/10(3). To date, none of the patients with MRD < or = 1/10(3) (good molecular responder) has relapsed. Classification according to molecular response at the end of induction did not correlate with the conventional risks groups: there were no statistically significant differences between good and bad molecular responders. Of particular interest is the absence of correlation between WBC at diagnosis and MRD level at the end of induction. We conclude that classification of patients into good and bad molecular responders using PCR seems to be a better prognostic indicator than conventional risk factors in childhood B-lineage ALL. Patients with MRD level > 1/10(3) have a particularly poor outcome and should always be considered for alternative therapeutic strategies in the future, whereas in good molecular responders belonging to poor or intermediate risk categories, treatment de-escalation might be contemplated.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

An EIA method on single donor solubilized HLA antigens for the identification of anti-HLA antibodies.

An enzyme immunoassay (EIA) method based on solubilized human leucocyte antigens (HLA) derived from single donor platelets is described. The EIA results on these solubilized single donor HLA antigens (SDszHLA) correlated well with the complement dependent cytotoxicity (CDC) results on the lymphocytes of the same donors and also with the panel reactivity (PRA) in CDC. A concordancy rate of 78% was found for individual HLA specificities. The EIA+/CDC- ('false positive') discrepancies were more pronounced than EIA-/CDC+ ('false negative') discrepancies and varied for the different donors. To confirm discrepancies, our method was compared with a commercial PRA-STAT EIA method (based on secreted soluble HLA antigens). The same discrepancies between CDC and PRA-STAT EIA were found and are probably due to the higher and different sensitivity (e.g. non complement fixing antibodies) of EIA methods. A SDszHLA EIA method allows the identification of HLA specificities of HLA-antisera. The possibility of using individual and selected donors for the production of SDszHLA allows the directed search for well defined HLA specificities in order to confirm anti-HLA specificities found in other anti-HLA screening methods. An individualized HLA panel can be established with the support of blood banks that have HLA typed blood and platelet donors.

Antibody Specificity↗
PubMed1997

Hematopoietic stem cell transplantation for sickle cell anemia.

Hematopoietic stem cell transplantation is the only therapy able to cure sickle cell anemia at the present time. So far, transplantations have been undertaken in approximatively 140 sickle cell patients all over the world, with good results. The selection of patients for transplantation remains a subject of dilemma because of the unpredictable course of the disease and the lack of valuable prognostic markers. The selection criteria accepted so far concern young patients under the age of 16, with a morbid course of the disease and having a HLA-compatible sibling. In Belgium, patients going back to their country of origin were also considered for transplantation. For 100 patients who underwent transplantation in Europe, the current Kaplan-Meier estimates of overall survival, event-free survival, and disease-free survival rates are 90%, 79%, and 81%, respectively. Benefits and side effects are analyzed.

Adolescent↗
PubMed1996

Hydroxyurea for treatment of severe sickle cell anemia: a pediatric clinical trial.

Hydroxyurea (HU) enhances the synthesis of fetal hemoglobin (HbF) and can improve the clinical course of some adult patients with sickle cell anemia (SCA). In a randomized trial, we studied the biologic effects and the clinical benefit of HU in children and young adults with severe SCA. Twenty-five patients (median age, 9 years) were randomized to receive either HU (at the initial dosage of 20 mg/kg/d) or a placebo for 6 months and were then switched to the other arm for the next 6 months. Among the 22 evaluable patients (median age, 8 years), significant increases in HbF and mean corpuscular volume occurred during the HU treatment period. The white blood cell and reticulocytes counts decreased significantly, but these changes were not clinically relevant. Sixteen of 22 patients (73%) experienced a complete disappearance of events requiring hospitalization. The number of days of hospitalization as well as the number of hospitalizations for patients on HU, as compared with those for the patients receiving placebo, were significantly reduced. We conclude that treatment with HU in children and young adults is feasible, well-tolerated, and improves the clinical course of SCA. The long-term effects of HU require further investigation.

Adolescent↗
PubMed1996

A single center evaluation of the Collaborative Transplant Study (CTS) DNA project.

Historical HLA class II serological typing results of transplantations performed in "The Leuven Collaborative Group for Transplantation" were subjected to retrospective Restriction Fragment Length Polymorfism (RFLP) DNA control typing by the Collaborative Transplant Study (CTS) DNA project using Polymerase Chain Reaction (PCR)-based DNA methods. We re-evaluated the serology/ RFLP-discrepant CTS DNA data for our local patients transplanted during a historical period (January 1988 until May 1992) before any class II DNA typing was performed in our tissue typing laboratory. These retyping results confirm both the CTS data for patient typing and the Eurotransplant data for donor typing. A confirmed high discrepancy rate of 19.0% (after exclusion of 2.2% transcription errors) was found in the patient population. A low discrepancy rate of 6.8% (after exclusion of 2.2% transcription errors) for the donor population is concordant with the Eurotransplant donor data. Only 4 of the 588 individuals were found to be incorrectly typed by the RFLP method; all involving the specificities DRB1*1102. This indicates that RFLP typing, as performed by the CTS DNA project, can be considered a valid, retrospective DNA typing system for the accurate interpretation of class II matching in organ transplantation. A second conclusion to be drawn from this study is the need for prospective DNA typing for kidney transplant recipients, as the discrepancy rate in this cohort is high. Our results suggest that with good quality serological HLA-DR typing, prospective donor DNA typing is not urgently needed.

Belgium↗
PubMed1996

Radiographic skeletal survey and radionuclide bone scan in Langerhans cell histiocytosis of bone.

BACKGROUND: The lack of a consensus in the literature on the imaging strategy in Langerhans cell histiocytosis (LCH) bone lesions in childhood. OBJECTIVE: To evaluate the relative value of radionuclide bone scan (RBS) and radiographic skeletal survey (RSS) in the detection of LCH bone lesions, both in the initial work-up of the disease and during the follow-up period. MATERIALS AND METHODS: Ten children with bone lesions evaluated by means of RSS and RBS in a retrospective study (1984-1993). RESULTS: Fifty radiologically and/or scintigraphically abnormal foci were detected: 27 anomalies in the initial work-up (12 by both RSS and RBS, 8 by RSS only and 7 by RBS only) and 23 additional anomalies during follow-up (10 by both RSS and RBS, 10 by RSS only and 3 by RBS only). RSS+/RBS- lesions (n = 18) are more frequently encountered in the skull (P = 0.038), and more frequently lack radiologic signs of osteoblastic activity (P = 0.020), than RSS+/RBS+ lesions (n = 22). RSS-/ RBS+ abnormalities (n = 10) were most frequently insignificant. CONCLUSION: In the initial work-up both RSS and RBS should be carried out, while in the follow-up only RSS should be performed.

Adolescent↗
PubMed1996

Persistence of fetal hemoglobin production after successful transplantation of cord blood stem cells in a patient with sickle cell anemia.

A girl with sickle cell anemia was treated with cord blood transplantation combined with hematopoietic growth factor. Cord blood cells were collected from a sister with an identical human leukocyte antigen complex who was a carrier of the sickle cell trait (hemoglobin AS). The patient had complete engraftment and no graft-versus-host disease. The persistence of a high level of fetal hemoglobin 6 months after engraftment was noted.

Anemia, Sickle Cell↗
PubMed1996

Bone marrow transplantation for sickle cell anemia.

The use of bone marrow transplantation for hemoglobinopathies was first proposed in thalassemia major and is now the therapy of choice for young patients affected by this disorder and having a suitable donor. Even though bone marrow transplantation is very effective in treating sickle cell anemia, enthusiasm for it is restrained by the unpredictable course of the disease. Selection criteria are difficult to establish and vary among medical teams and their patients' characteristics. Some of the factors playing a role in the decision are summarized in this article. They include genetic and environmental factors, features of the patient such as age or the presence of organ damage, and the possibility of using new alternative therapeutic approaches.

Anemia, Sickle Cell↗
PubMed1995

Tropisetron in the prevention of nausea and vomiting in 131 children receiving cytotoxic chemotherapy.

Tropisetron (Navoban, Sandoz Pharma Ltd., Basel, Switzerland), a selective antagonist of the serotonin receptor (5-HT3) dosed once-daily at 0.2 mg/kg (with a maximum of 5 mg daily), was evaluated in the prevention of chemotherapy-induced nausea and vomiting in 131 children with a median age of 5 years (age 10 weeks to 21 years). Acute lymphocytic leukemia was the most common malignancy (49%). Most children (82%) had received cytotoxic chemotherapy before enrollment. Patients received tropisetron during one or more courses of chemotherapy (455 courses in total). Tropisetron was administered slowly intravenously as a single dose before the start of chemotherapy on day 1 and intravenously or by mouth the subsequent days as a single daily dose (median treatment duration: 5 days). Response to tropisetron per 24 hour period on the first 5 days of each chemotherapy course was graded as complete (absence of both nausea and vomiting), partial (one to four vomits and/or less than 5 hours of nausea), or failure. Overall complete response on day 1 was observed in 305 out of 455 chemotherapy courses (67%). The patients receiving intravenous chemotherapy (N = 92) had a 70% complete response rate and a 26% partial response rate on day 1, both for course 1 and course 2. The percentage of complete responders increased the subsequent days of the course. Emesis after day 1 was observed primarily during courses with the most emetogenic chemotherapy. No side-effects of tropisetron other than a single case of diarrhoea were documented in this study.

Adolescent↗
PubMed1995

Control of nausea and vomiting by Navoban (tropisetron) in 131 children receiving cytotoxic chemotherapy.

One hundred and thirty-one children with a median age of 5 years were administered Navoban (tropisetron), a selective antagonist of the serotonin receptor (5-HT3), dosed once daily at 0.2 mg/kg (with a maximum of 5 mg daily) in a study aimed at evaluating the prevention of nausea and vomiting induced by anti-cancer chemotherapy. The most common malignancy (in 49% of patients) was acute lymphocytic leukaemia. Patients received Navoban during one or more courses of emetogenic chemotherapy for a total of 455 courses administered intravenously or intravenously and intrathecally (IV + IT). Most patients (89%) had already received cytotoxic chemotherapy before enrollment for the trial. On Day 1, Navoban was administered slowly and intravenously as a single dose before the start of chemotherapy, or by mouth as a single daily dose on subsequent days (median treatment duration = 5 days). On the first 5 days of each course of chemotherapy, response to Navoban per 24-hour period was graded as: complete (absence of both nausea and vomiting), partial (1-4 vomits and/or less than 5 hours of nausea), or failure (more than 4 vomits and/or at least 5 hours of nausea). Ninety-six per cent of the intravenous chemotherapy group and 97% of the IV + IT chemotherapy group had a complete (70% and 55% respectively) or partial (26% and 42% respectively) response during the first 24-hour period of the first course in which Navoban was used. The second and subsequent courses yielded similar percentages. Delayed emesis was observed mainly during those courses employing the most emetogenic chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗