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K Schnabel

Publications and source records attributed to K Schnabel.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Tumor markers as prognostic factors in non-small-cell bronchial carcinoma].

PURPOSE: Considerations of different therapeutic approaches require a realistic estimation of the prognosis. The usefulness of tumor markers as prognostic indicators was evaluated by means of a multivariate analysis. PATIENTS AND METHODS: The data of 300 patients who had been irradiated for their primary tumor were analysed retrospectively. The serum concentrations of CEA, SCCA, NSE, and LDH were available before treatment and 3 months thereafter in a sufficient number of cases. The prognostic factors for survival and progression-free survival resulting from univariate tests were further evaluated by a Cox-proportional-hazards model. RESULTS: The serum levels of the particular tumor markers were pathologically elevated in 25 to 36.5% of the cases. Their values correlated with the stage of the disease and separately the N-stage too. A normalization of increased marker levels after irradiation occurred in 37.5 to 67% of the cases. Survival of patients with increased pretherapeutic values of CEA, SCCA, and LDH was significantly worse compared to those with normal values. In the case of a post-therapeutic return to normal levels, prognosis was significantly better than for those where the elevation persisted. However, after inclusion of all other parameters in multivariate analysis the tumor markers were meaningless. Karnofsky-performance status, total dose of radiotherapy, stage of the disease, and weight-loss evolved as independent prognostic factors for survival. For progression-free survival only stage of the disease was important. All subgroup analyses (restriction on patients with favorable prognosis) showed the same results. CONCLUSIONS: A prognostic importance of NSE could not be demonstrated. CEA, SCCA, and LDH were univariate predictors for survival and progression-free survival. But they proved to be dependent on the stage of the disease and were not confirmed as independent variables in the Cox-model. Their importance during the follow-up is diminished by the frequent lack of therapeutic approaches in the case of disease progression. Certainly a more favorable prognosis in case of a post-therapeutic normalization of previously elevated values was found.

Biomarkers, Tumor↗
PubMed1994

Neuroinvasion and persistence of human herpesvirus 6 in children.

Human herpesvirus 6 (HHV-6) causes a febrile illness in children and has been implicated as a cause of encephalitis and recurrent seizures. Paired samples of cerebrospinal fluid (CSF) and peripheral blood mononuclear cells (PBMC) from 487 children were evaluated by nested polymerase chain reaction (PCR) for evidence of current or past infection with HHV-6. PBMC were also cultured for isolation of HHV-6. These data were correlated with the patients' clinical information. HHV-6 DNA was detected in 72 (14.8%) of 487 CSF samples. HHV-6 persistence was documented in 142 children by PCR detection of HHV-6 DNA in PBMC or CSF (or both) in the absence of primary HHV-6 infection; the central nervous system was the only site of HHV-6 DNA persistence in 28.9%. HHV-6 DNA can be detected in the CSF of children during and after primary infection, and the central nervous system may be the sole site of persistence.

Child, Preschool↗
PubMed1994

[The radiotherapy of brain metastases in bronchial carcinoma].

PURPOSE: The data of 132 patients who were treated between 1983 and 1992 because of cerebral metastases from lung cancer were retrospectively analysed, in order to find criteria for patients selection to radiotherapy with simultaneous application of corticosteroids. METHODS: Radiotherapy was given either in 10 fractions of 3 Gy over 2 weeks (97 patients) or in 20 fractions of 2 Gy over 4 weeks (35 patients), always in form of a whole-brain irradiation. Before and during radiotherapy dexamethasone was administered. RESULTS: The local remission rate was 56% for both treatment schedules. In cases with a complete remission median survival was significantly longer compared with partial remission or no change. The median survival of the whole group was 4 months. Patients with extracerebral metastases and a Karnofsky-score < 7 or brain metastases > or = 2.5 cm had a median survival of only 2 months, whereas patients with only brain metastases and a Karnofsky-score > or = 7 or brain metastases < 2.5 cm had a median survival of 6 months. 11% of the patients were asymptomatic. A symptomatic relief, additional to the effect of corticosteroid therapy, was found in 43% of cases, which was dependent on local remission and tendencially on dose of corticosteroids. In a multivariate analysis performance status, extracerebral metastases, and size of cerebral metastases were found to be prognostic parameters. CONCLUSION: Radiotherapy with 10 x 3 Gy seems to be appropriate for the majority of patients, when expense and hospitalisation time are compared with results and benefit. Selected patients may profile from a more aggressive treatment approach. In some cases radiotherapy may be an unsuitable overtreatment.

Adrenal Cortex Hormones↗
PubMed1993

[Radiologic assessment of suspected orbital fracture].

In suspicion of orbital fractures plain X-ray of the skull in half axial view are recommended. To be sure of this diagnosis one need to do examinations in high resolution computed tomography, axial and coronal view, in order to demonstrate the total extension of the fracture and lesions of the soft tissue of the orbit and of the surrounded areas. Magnetic resonance tomography is helpful in demonstrating fat and muscles around or in the fractures. There is no need to do other projections of plain skull X-rays except there is no computed tomography available.

Frontal Bone↗
PubMed1993

[Hyperfractionated irradiation of non-small cell bronchial cancer. Final results of a Phase II study].

The study was performed for the evaluation of hyperfractionated radiotherapy in the treatment of non-small-cell lung cancer. From radiobiological data we expected that the twice daily irradiation with reduced single dose should result in a better sparing of the slowly proliferating healthy lung tissue without any loss in the tumoricidal effect. 34 patients were treated conventionally with 30 daily fractions of 2.0 Gy over six weeks and another 34 patients twice daily with 1.3 Gy over five weeks to a total dose of 65 Gy. The interval between two fractions lasted at least six hours. Life table (Kaplan-Meier estimate) indicated no contrast between the therapy schedules. The treatment groups did not differ in local response of the primary, progression-free interval and occurrence of distant metastases, the hyperfractionated schedule was very well tolerated. Comparison of the posttreatment quality of life showed a better course after the hyperfractionated regimen, without reaching a level of significance.

Adenocarcinoma↗
PubMed1992

Phenotypic and genetic polymorphisms among human herpesvirus-6 isolates from North American infants.

Fifteen human herpesvirus-6 (HHV-6) isolates from North American infants with primary infection manifest as febrile or roseola (exanthem subitum) like illnesses were characterized phenotypically on the basis of their in vitro growth in continuous T-cell lines and primary human mononuclear cells and by their reactivity with monoclonal antibodies. All isolates replicated efficiently in primary human cord blood mononuclear cells, but five distinct patterns of viral replication in human cells lines were observed. Two of the HHV-6 isolates from infants were found to replicate in HSB-2 cells, a property associated with so-called group A viruses, which had previously been isolated only from adults. These same isolates also reacted with a panel of A-specific monoclonal antibodies. Genomic characterization of viral isolates using well-characterized restriction site polymorphisms indicated that these two isolates contained a mixture of both A- and B-type genomes, in different proportions. These data suggest that not all HHV-6 isolates can be categorized into one of two broad groups and that such segregation of HHV-6 isolates may in fact be misleading.

Cell Line↗
PubMed1990

[The superior vena cava syndrome as an emergency in radiotherapy].

Between 1983 and 1988 90 patients with bronchial neoplasms needed emergency irradiation to treat superior vena cava syndrome. Pathohistologically verified were 30 cases with squamous cell carcinoma, twelve with adenocarcinoma, five cases with large cell carcinoma, 30 with a small cell carcinoma, and non-differentiated in five others. No histological examination was carried out in eight cases. Im 30 patients distant metastases were evident at the initial diagnosis. The average duration of follow-up was 118 days. The survival course proved to be independent of histopathological grading, previous treatment, and age. Similarly no influence of the fractionation employed could be seen. Very important to the prognosis however, were the stage of disease, the Karnofsky index, and dependent on that, the total reference dose applied. Patients with a Karnofsky index of 50% or lower survived on average only 17 days.

Adenocarcinoma↗
PubMed1990

[A simple method for positioning and fixing the extremities during the radiotherapy of soft-tissue sarcomas].

The exact and reproducible radiotherapy of malignant tumours in the extremities is aided by reliable positioning of the involved limb. In our department individually-formed casts and circular fix up made of two-component polyurethane foam (NEOFRAKT, supplied by Schumacher, Krefeld, FRG) are used. These allow the maintenance of any bending, stretching and torsional positions. The fields to be applied are cut out of the casts, thus preventing any influence on the depth dose of the radiation involved.

Arm↗
PubMed1988

Plastic material used to optimize radiotherapy of head and neck tumors and the mammary carcinoma.

In order to improve head and neck tumor therapy, face masks were developed. The physical and mechanical properties of 11 apparently suitable materials were tested using a phantom. According to our studies "HEXCELITE" (supplied by Medimex, Hamburg, F.R.G.) proved to be the best material. Plastic breast molds were made to optimize the dose distribution for radiation therapy with fast electrons of post-mastectomy breast tumors. Here too the mechanical and physical properties of nine different materials were tested. The most suitable of these proved to be the gel mat "PRIMAMED" (supplied by Schülke and Mayr, Norderstedt, F.R.G.). The two materials mentioned have been well tolerated by more than 200 patients.

Bandages↗
PubMed1988

Long-term monitoring of treatment with recombinant human growth hormone by serial determinations of type III procollagen-related antigens in serum.

Inasmuch as recombinant human growth hormone is now more generally available for the treatment of different types of short stature, there is a need for better short-term indicators of treatment success. In healthy children, serum concentrations of antigens related to the aminoterminal propeptide of type III procollagen (P-III-NP) closely follow the growth velocity curve. P-III-NP was measured longitudinally in 20 children with growth hormone deficiency during 6 months of human growth hormone substitution therapy. Two different radioimmunoassay systems were used; one recognizes predominantly the intact propeptide showing a lesser affinity to a smaller monomeric peptide (RIAgnost assay), while the other assay detects both forms equally (FAB assay). These results were compared to the growth response [median 5.6 (0.4 to 13.9) cm in 6 months] and to other established growth correlated parameters (somatomedin C, alkaline phosphatase). A relatively better growth response correlated significantly with high pretreatment P-III-NP (RIAgnost assay) values (r = 0.56) and delayed bone age (r = -0.70). A combination of these parameters in multiple regression analysis increased the cumulative prediction value to above 60% (r2 = 0.61). On the other hand, P-III-NP (FAB assay) values proved to be best in monitoring treatment, correlating with the individual growth rate during the first 3 months (r = 0.40; p less than 0.05), during the consecutive 3 months (r = 0.66; p less than 0.001), and during the total 6-month period (r = 0.46; p less than 0.05). All other parameters showed associations to growth only during some treatment periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

[A simple device for positioning and fixing the head in radiotherapy of brain tumors in frontal and lateral position].

In radiotherapy of cerebral tumors in the occipital, central, and parietal area it can be favourable to fix the patient's head in frontal or lateral position. It is true that this problem can be solved by manufacturing individual face masks of PVC with the vacuum deep-drawing method, but this method is very time- and cost-consuming. The present study suggests a simplified method using the thermoplastic polyester "Orfit". Such a mask provides a good immobilization and can be manufactured in 10 to 15 minutes without bothering much the patient. Simulation and computed tomography are not substantially affected by the material.

Brain Neoplasms↗
PubMed1987

[Hyperfractionated irradiation of bronchial cancer. Results of a pilot study].

The results achieved during recent years in experimental radiotherapy of malignant tumors show more and more the benefit provided by the small individual doses applied in fractionated irradiation. The effects and side effects of a hyperfractionated therapy of the bronchial carcinoma were investigated in a not randomized comparative study. The data of 100 patients were available for evaluation; they showed a tendency to local superiority of hyperfractionated irradiation. The value of hyperfractionation shall be examined in detail in a randomized prospective study.

Carcinoma, Non-Small-Cell Lung↗