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J Michaelis

Publications and source records attributed to J Michaelis.

139 records · Page 8Linked to original sources
PubMedDate not supplied

[Preoperative chemotherapy of nephroblastoma. Preliminary results of the SIOP-9/GPO therapy study].

The therapeutic strategy of the SIOP-9 study includes pre-operative chemotherapy for all patients with nephroblastoma diagnosed by imaging methods aged between 0.5 and 16 years. By pre-operative chemotherapy the rate of radical resectable tumors should be increased and thereby the intensity of postoperative therapy, in particular of radiotherapy, diminished. Patients with nephroblastoma stage I-III were in case of tumorresponse randomised in either a 4 weeks or 8 weeks arm of pre-operative treatment with ACT D and VCR. The question was, if a prolongation of pre-operative chemotherapy could increase the relative part of stage I. Between 1/1/89 and 6/30/91 from 49 oncologic centres of former western Germany 188 patients were registered in the SIOP-9/GPO. From the stage I-III patients between 0.5 and 16 years 80.1% were pretreated with cytostatic agents. Only 53.9% of the patients with tumorresponse were randomised. The relative frequency of intraoperative ruptures was with 3% lower in the group of pretreated patients than in the primary operated (15.3%). The stage distribution for all Wilms' tumor patients showed a prevalence of stage I with 43.3% (after pre-operative treatment 59%; after primary operation 28%). Abdominal radiotherapy was performed in 22.4%. The event-free survival rate of all nephroblastoma lay at 85% 3 years after diagnosis (stage I standard 96%; unfavorable histology all stages 45%). 7.3% of the patients developed a hepatopathy under treatment and 7.8% even a VOD according to the criteria of McDonald.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

[The "Lower Saxony/Northern Rhine-Westphalia" Neuroblastoma Screening Project: on the need for epidemiologic comparison].

The proof for the general evolution of metastatic neuroblastoma from localized disease by a low-speed process is lacking. The epidemiological approach would require the decrease of neuroblastoma related mortality by reduction of the number of metastatic cases per population unit as a result of a screening program. During 1983 through 1990 the neuroblastoma incidence in the FRG was 0.85-1.09 cases per 100,000 children less than 15 years of age. The mortality rate ranged between 0.25 and 0.49 deaths per 100,000 children. The project "Niedersachsen/Nordrhein-Westfalen" started April 1st, 1992 and is investigating urinary catecholamine metabolite excretion in infants at the age of 10-12 months and for a second time in toddlers at 17-19 months. The target population includes 24.7 million inhabitants with 267,000 births per year. The urine sampled on filter paper is analyzed using thin layer chromatography. Positive and questionable positive results are confirmed by HPLC and GC-MS. The aim of the study is to demonstrate the feasibility of the chosen approach. Furthermore first epidemiological data will be obtained. Until a population-based study on neuroblastoma mortality in screened versus controlled populations has proven the usefulness of the screening it cannot be recommended as a general service to the public.

Adolescent↗
PubMedDate not supplied

[Medulloblastoma therapy studies MBL 80 and MED 84 of the Society of Pediatric Oncology and the Société Internationale d'Oncologie Pédiatrique (SIOP)].

In both trials the principle of "sandwich" chemotherapy (administered between surgery and postoperative irradiation) is studied in medulloblastoma. GPO-MBL 80 was essentially a one-arm trial; results after a mean observation period of 3 years show an expected event-free survival rate of 46% at 6 years. "Maintenance" chemotherapy with CCNU and vincristine did not further improve the results. Preliminary results of the joint, prospective, randomised forearm SIOP-GPO trial MED 84 are presented. It is apparently too early to answer any of the two main questions asked by this trial: a) is "sandwich" chemotherapy (as administered) of any value? b) can radiotherapy doses to the supratentorial area and to the spine be moderately reduced in so-called "low risk" patients without compromising long-term results? Thus far, we cannot observe any prognostic influence of the "classical" risk factors as established by other studies.

Adolescent↗
PubMedDate not supplied

[The Cooperative Ewing Sarcoma Study CESS 81 of the German Pediatric Oncology Society--analysis after 4 years].

In 1981 the cooperative Ewing's sarcoma study CESS 81 was initiated with initial 18-weeks-chemotherapy consisting of vincristine, actinomycin D, cyclophosphamide and adriamycin (VACA) followed by local therapy consisting of either radical surgery with complete resection of the involved bone or incomplete resection followed by radiation with 36 gy or radiotherapy only. Patients with radiation only for local therapy and extremity tumor sites are randomised for 46 gy vs 60 gy tumor dose. Following local therapy chemotherapy is continued for an additional 18 weeks. The actuarial results of 83 consecutive patients entered from 51 participating institutions from January 1, 1981, until November 15, 1984 are presented. 68/83 patients were off therapy and under observation for longer than one year following diagnosis. The longest follow-up was 41 months. On November 15, 1984, 39/68 (57%) patients were disease free. According to the site of the primary tumor patients with distal extremity lesions had a more favourable prognosis as compared to proximal extremity and central lesions. According to local therapy patients with radical surgery had a better prognosis as compared to those with resection followed by radiation and those with radiation only for local control. Analysis according to tumor volume revealed the strong interaction between tumor site, local therapy and tumor volume. According to life-table-analysis the disease free survival for patients with a tumor volume less than 100 ml was 75% after 41 months compared to 10% for patients with a tumor volume greater than or equal to 100 ml. The consequences of this analysis for a stratified treatment regimen for patients with primary Ewing's sarcoma of bone are discussed.

Adolescent↗
PubMedDate not supplied

German case control study on childhood leukaemia--basic considerations, methodology and summary of the results.

In order to explore potential risk factors of childhood leukaemia, a case control study was performed including all incident cases from 1992 to 1994. The study was based on the German Childhood Cancer Registry. It was restricted to cases from West Germany and extended retrospectively until 1980 for children who were living in regions covered by a previous incidence study on nuclear installations (21). The study was conducted in close correspondence with a preceding case control study in Lower Saxony (13). Results of this study and of others published in the literature were used to define explicit hypotheses for the present study. This paper presents the methodology of the study and gives an overview of some basic results. More detailed analyses of the investigated potential risk factors will be published elsewhere. The study comprised a total of 2358 cases (leukaemias, lymphomas, selected tumours) and 2588 controls. Response rates were 81% for cases and 67% for controls. For leukaemias, the main results regarding maternal factors, pregnancy, birth, immune system, ionising radiation, parental occupation and environmental factors were as follows: Positive associations were observed between childhood leukaemias and young maternal age at birth, high birth weight, tonsillectomy and use of pesticides. Some results suggest a protective effect for allergies and vaccinations. A negative association was observed with maternal smoking and childhood leukaemia. No associations were found with frequency of stillbirths, maternal alcohol consumption, parental exposure to benzene and use of wood preservatives. X-ray examinations in early childhood and parental radiation exposure did not show any consistent associations with leukaemia. Potential risk factors were not reported more frequently by cases and controls living in 114 communities with increased incidence rates. The strength of our study lies in the large number of participating families and in the population-based approach.

Adolescent↗
PubMedDate not supplied

Case control study of neuroblastoma in west-Germany after the Chernobyl accident.

BACKGROUND: To explore possible causes of a 1988 incidence peak of infant neuroblastoma in west German regions which were contaminated with more than 6000 Bq/m2 Cs137 from the Chernobyl accident. The primary working hypothesis was that parents of the diseased children had been contaminated by an excessive intake of locally produced food, especially mushrooms or deer. DESIGN: Case control study with 1:2 (cases:controls) matching. Data were collected from the children's parents by questionnaires and telephone interviews. SETTING: Nation-wide study (former FRG) based on the German Childhood Cancer Registry. SUBJECTS: Cases born in 1988 and reported with a neuroblastoma to the registry until March 1992. Population-based healthy controls, matched for age, sex and residence at time of diagnosis. RESULTS: The working hypothesis could not be confirmed by the study, because the parents of cases tended to eat less locally grown food than the parents of controls (RR = 0.63, 95% CI:0.20-1.97). Possible influence factors which previously have been described to be associated with neuroblastoma incidence could not be confirmed by the study. Parental exposure to herbicides and pesticides was associated with the occurrence of neuroblastoma (RR = 4.2, 95% CI:1.4-12.9). Neuroblastoma stage distribution in the contaminated regions was shifted towards lower stages as compared to the less contaminated regions and previous age cohorts. CONCLUSIONS: The study does not show additional evidence that the observed increase in neuroblastoma incidence might have been caused by exposure to fallout from the Chernobyl accident. The observed shift towards lower clinical stages may rather indicate increased diagnostic awareness. The association between neuroblastoma and parental exposure with herbicides and pesticides resulted from an extensive exploratory data analysis and needs to be confirmed in further studies.

Child, Preschool↗
PubMedDate not supplied

Case control study on childhood leukemia in Lower Saxony, Germany. Basic considerations, methodology, and summary of results.

In two municipalities in Lower Saxony statistically valid clusters were observed, which attracted great public interest. Committees were set up to initiate a large variety of on-the-spot-investigations. Finally, it was decided to conduct a case control study throughout Lower Saxony to explore potential risk factors which might explain the observed clusters. A limited number of already established and currently discussed hypotheses was chosen for investigation. The study was based on patients registrated at the German Children's Cancer Registry (GCCR). For each child with leukemia diseased between 1988 and 1993 two population-based controls (local and state controls) and one tumour control were selected. Data were collected by means of a questionnaire self-administered by the parents and a telephone interview. In addition, measurements of electromagnetic fields and radon were performed and inspections of the child's birth record were made for the purpose of confirming a potential association between parenteral vitamin K prophylaxis and leukemia or tumours. This paper presents the concept and basic considerations of the study, its design and statistical evaluation. Response rates and a summary of results will be presented, too. The paper will serve as a reference for subsequent publications about more detailed analyses of specific potential risk factors. 425 parents of diseased children and 610 of non-diseased children were asked for participation. The rates of response were 82% for families with diseased and 71% for families with non-diseased children. In total, 781 parents participated in the study. The most important results are as follows: The Greaves' hypothesis (9, 10) was supported by the following results: In children diseased with leukemia, vaccinations were less frequent, virus-related infections occurred more rarely, these children were more frequently first-born children and more frequently breast-feed, and they possibly had fewer contacts with other children in infancy. Our data do not show a significant association between parenteral vitamin K prophylaxis and leukemia or tumours (17). Measurements of electromagnetic fields show a weak association between high-level exposure and an increased risk of developing leukemias. Children who were X-rayed more than four times or were born prematurely and had received intensive care treatment show a positive association with occurrence of leukemia, but the number of these patients was very small and these factors are not independent. The only potential job-related hazard was paternal exposure to plastic and resin fumes. The incidence of miscarriages and abortions was increased in mothers of children with leukemia. Our study did not confirm the hypotheses, that leukemia is associated with gestational age, with consumption of alcohol, nicotine, and medicaments during pregnancy. Nor was any association detected with exposure to wood preservatives and insecticides or with a high socio-economic status. The number of patients living in municipalities with increased incidence of leukemia was too small to show statistically valid results. However, it is noteworthy that some of the above-mentioned risk factors were observed also in these children. One of the purposes of a nation-wide case control study which is currently performed at the GCCR is to validate and complete these results.

Case-Control Studies↗
PubMedDate not supplied

[Second neoplasms after malignant diseases in childhood].

Since 1980 the German Registry of Childhood Malignancies has been established. In the framework of the long-term follow-up secondary malignancies are reported continually to the registry. An additional retrospective inquiry to all treating clinicians and principal investigators of clinical trials as well as a link to a previously existing pool of secondary malignancies (1) lead to a completion of the data. At the registry now 329 patients with second malignant neoplasms have been observed. 41.3% of them had been developed the first malignancy before the registry started its work in 1980. The most common primary malignancies are acute lymphoblastic leukaemia (ALL, 28.6%), brain tumours (12.2%), and retinoblastomas (8.8%). Compared to the population of the registry retinoblastomas as a secondary malignancy occur in excess (2.5% vs 8.8%). Most common secondary malignancies are brain tumours (20.1%), acute non-lymphoblastic leukaemia (13.1%), osteosarcomas (10.9%), and thyroid carcinomas (6.1%). Hereby especially for thyroid cancer a remarkable deviation from the frequency in the total population of the registry (0.2%) is observed. In 3% of the patients a secondary malignancy appears within a span of 10 years after the primary malignancy. This is a twentyfold increase compared with the cumulative rate of developing a malignancy in the first 10 years of life. Brain tumours after ALL (8.5%) and after other brain tumours (5.8%) and osteosarcomas after retinoblastomas (4.9%) are the most often reported combinations.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

[Establishment of a uniform common data set for pediatric oncology. Applied Informatics Study Group of the GPOH (Society of Pediatric Oncology and Hematology)].

Large multicenter trials have made a major contribution to the improvement of treatment results in childhood malignancies. Coordination and central documentation ensure the quality of treatment and permit clinical and scientific investigations. This kind of cooperation requires a vast amount of documentation, which by itself has become a critical factor in answering important medical questions. The problems result from non-standardized documentation systems in different studies, from insufficient integration of clinical work and documentation and from a lack of application of modern computer based data management systems. The working group "Applied Informatics" of the German "Gesellschaft für Pädiatrische Onkologie und Hämatologie (GPOH)" has started a project to create an uniform basic data set for the German pediatric oncology group. Relevant initial diagnostic data, information about planned and realized treatment as well as data concerning negative event had to be standardized. A minimal common data set with a substantially reduced documentation, which is applicable for all patients and trials, would have failed to fulfil the clinical as well as the research needs. The data set presented here is a detailed information structure introduced as a basic tool for the improvement of data management in the German pediatric oncology group. This first version of the basic data set will need further development, since some of the problems still need to be resolved and the requirements for such data pools are changing. Based on this data set new computer software and clinical information systems have to be developed to enable documentation and processing of all clinical and study related data.

Child↗
PubMedDate not supplied

Prevention of childhood leukemia by BCG vaccination in newborns? A population-based case-control study in Lower Saxony, Germany.

Data from a case-control study in Lower Saxony, Germany, were used to assess whether the risk for childhood cancer may be reduced by bacille Calmette-Guérin (BCG) vaccination in the neonatal period. There were 420 newly diagnosed childhood cancer cases from the German cancer registry and 613 controls eligible for this study. A mailed questionnaire was completed during a telephone interview with parents. Details on the perinatal history were abstracted from the birth charts by nurses blinded to the children's case-control status. Complete information was available for 259 cases and for 323 controls. A total of 85% of the controls had been BCG vaccinated in the newborn period. The adjusted odds ratios for BCG vaccination were 0.90 (95% confidence interval; 0.51-1.61) for leukemia and 0.61 (95% confidence interval; 0.25-1.50) for other cancers. Based on these data the probability of a 50% or more reduction of more reduction of the cancer risk by BCG vaccination in the newborn period is small. The statistical power of this study, however, was not high enough to rule out a smaller, still relevant reduction in cancer risk.

Acute Disease↗
PubMedDate not supplied

Hypotensive effects of peptide T in conscious rats.

1. The present study investigated the effects of peptide T on mean arterial blood pressure (MAP) in conscious normotensive Sprague-Dawley (SD) rats, spontaneously hypertensive rats (SHR) and two-kidney one-clip (2K1C) hypertensive rats. 2. Peptide T was infused via the left jugular vein at a rate of 1 mg/kg per h in SD, SHR and 2K1C rats and then at doses of 0.1, 0.25, 0.5, 1 and 5 mg/kg per h in SHR, with 0.9% saline as a sham control in SHR and 2K1C. Mean arterial pressure was measured directly before, during and after infusion. 3. Peptide T (1 mg/kg per h) decreased blood pressure in both SHR (P < 0.01) and 2K1C (P < 0.05). In normotensive SD rats the fall in MAP approached statistical significance (P = 0.06). The effect of peptide T was not significantly different in normotensive compared with hypertensive rats. Saline infusion had no effect. The blood pressure lowering effect of peptide T appeared to be dose-dependent in SHR.

Animals↗