Search PubMed⌕ Search

Biomedical subjects

H Schicha

Publications and source records attributed to H Schicha.

At least 19 recordsLinked to original sources
PubMed2004

18F-FDG PET for detecting recurrent head and neck cancer, local lymph node involvement and distant metastases. Comparison of qualitative visual and semiquantitative analysis.

AIM: Assessment of the clinical value of (18)F-FDG-PET for detection of recurrent head and neck cancer, local lymph node involvement and distant metastases comparing a qualitative visual with a semiquantitative analysis (SUV values). PATIENTS, METHODS: Retrospective evaluation of 73 (18)F-FDG PET studies in 55 patients by use of a four-step qualitative visual grading system and calculation of standard uptake values in pathological lesions. Calculation of SUV values in normal regions for generating a map of physiological (18)F-FDG distribution. Correlation to histopathological findings and clinical follow-up. RESULTS: 1. Qualitative visual analysis of (18)F-FDG PET studies: a) local recurrence sensitivity 79%, specificity 97%, positive predictive value 95%, negative predictive value 85%, and diagnostic accuracy 89%; b) local metastatic lymph nodes 100%, 95%, 85%, 100%, 96%; c) distant metastases 100%, 98%, 86%, 100%, 98%, respectively. 2. Semiquantitative analysis had only little incremental, non-significant value in comparison to qualitative visual analysis for the detection of a local recurrence in two patients: a) local recurrence: sensitivity 83%, specificity 100%, positive predictive value 100%, negative predictive value 88%, and diagnostic accuracy 93%; b) local metastatic lymph nodes or c) distant metastases did not change in comparison to qualitative visual analysis. CONCLUSION: (18)F-FDG PET is an effective tool for re-staging of patients with suspected recurrence after therapy for head and neck cancer.

Carcinoma, Squamous Cell↗
PubMed2004

[Overtherapy or undertherapy for papillary thyroid microcarcinoma? Therapeutic considerations for radioiodine ablation].

Papillary thyroid microcarcinomas </=1 cm have an excellent prognosis both in terms of overall and relapse-free survival. Their high prevalence in autopsy series suggests that most papillary microcarcinomas do not progress to clinically relevant cancer. The extent of surgery is still controversial. Lobectomy or subtotal resection are standard procedures, but multifocal microcarcinomas or lymph node metastases might be overlooked. The pros and cons of completion thyroidectomy and ablative radioiodine therapy are based on limited evidence due to heterogenous inclusion criteria in published series. The retrospective data analyses included subgroups with infiltration of the thyroid capsule, lymph node metastases or multifocal microcarcinomas at the primary staging. The local relapse rate reached approximately 7% after different therapeutic regimes. Radioiodine ablation decreased the recurrence rate in some retrospective studies, but data are inconsistent. Successful radioiodine ablation is possible also after less radical surgery without complete thyroidectomy with postoperative (131)I uptake of 10 to 20% or remnants of 3-8 ml. This concept was evaluated successfully in a monocentric series of patients with multifocal microcarcinomas. The therapeutic consideration should include the diameter of the carcinoma, neighbourhood to the thyroid capsule, histopathologic sub-groups, age, familiar occurrence, patient's informed consent and in future moleculargenetic tests, too. There-fore, limited surgical procedures for small papillary carcinomas as therapeutic standard, respectively thyroidectomy, lymph node dissection in the central compartment of the neck and ablative radioiodine therapy for individual cases are options for experienced surgeons and specialized tumour centers.

Carcinoma, Papillary↗
PubMed2004

[Procedure guidelines for radioiodine therapy of differentiated thyroid cancer (version 2)].

The procedure guidelines for radioiodine therapy (RIT) of differentiated thyroid cancer (version 2) are the counter-part to the procedure guidelines for (131)I whole-body scintigraphy (version 2) and specify the interdisciplinary guidelines for thyroid cancer of the Deutsche Krebsgesellschaft and the Deutsche Gesellschaft für Chirurgie concerning the nuclear medicine part. Compared with version 1 facultative options for RIT can be chosen in special cases: ablative RIT for papillary microcarcinoma </=1 cm, ablative RIT for mixed forms of anaplastic and differentiated thyroid cancer, and RIT in patients with a measurable or increasing thyroglobulin concentration but without detectable metastases by imaging. The description of the pretherapeutic dosimetry now includes the isotopes (123)I and (124)I as well as a broader range of the activity of (131)I. Activities of 2-5 GBq (131)I are recommended for the first ablative RIT. If high accumulative activities of (131)I are expected, men who have not yet finished their family planning should be advised to the option of sperm cryoconservation. An interdisciplinary consensus is necessary whether the new TNM-classification (UICC, 6(th) edition, 2002) will lead to modified recommendations for surgical or nuclear medicine therapy, especially for the surgical completeness and for the ablative RIT of pT1 papillary cancer.

Contraindications↗
PubMed2003

[Basedown disease, thyroid gland autonomy, nodular goiter. When is radiotherapy indicated?].

Treatment options for benign diseases of the thyroid include medication, radioiodine therapy and surgery. Patients with hyperthyroidism initially receive antithyroid drugs, with further treatment determined by the relapse risk. In the case of Graves' disease this is determined by a number of risk factors, including the volume of the thyroid gland or the presence of endocrinal ophthalmopathy. In such cases with a high relapse risk, radioiodine therapy is the recommended first-line treatment. Further indications--if surgery is not necessary--are autonomous goiter, recurrent (autonomous) goiter and latent hyperthyroidism. A single radioiodine treatment suffices to control the situation in more than 90% of the cases, and the goiter clearly diminishes in size. Radiation-induced malignancies or malformations have not been seen, but iodine treatment is contraindicated in pregnancy. In view of the short hospital stay of only four to five days, and the ready availability of treatment units, the authors consider radioiodine therapy a suitable first-line option in patients with Graves' hyperthyroidism.

Antithyroid Agents↗
PubMed2003

[Hodgkin's lymphoma in nuclear medicine: diagnostic and therapeutic aspects].

Today, diagnostic and therapeutic strategies of Hodgkin lymphoma (HL) with positron emission tomography and radioimmunotherapy include state-of-the-art nuclear medicine which require the cooperation between oncology and nuclear medicine. The benefit of FDG-PET in HL patients with residual tumor masses consists of its high negative predictive value in the therapy control of the disease. The concept of waitful watching in patients with PET-negative residual masses after BEACOPP-chemotherapy will be evaluated in a large multicenter trial of the GHSG (German Hodgkin Study Group). Radioimmunotherapy has been performed in patients with CD20-positive Non-Hodgkin lymphoma for 10 years with promising results. HL is also an excellent target for immunotherapy due to the expression of antigens such as CD25 and CD30. Thus, a new radioimmunoconstruct consisting of the murine anti-CD30 antibody Ki-4 labeled with iodine-131 was developed for patients with relapsed or refractory HL.

Fluorodeoxyglucose F18↗
PubMed2003

[Reimbursement of the PET in oncology in Europe: a questionnaire based survey].

AIM: The discussion in Germany about the reimbursement of the (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in oncology should make use of the experience from the other European countries. METHOD: A questionnaire was sent to 23 PET-institutions in Europe, outside from Germany, in January 2003. The questions were about the number of PET-institutions, the regulations for reimbursement, the accepted indications, the recognized types of PET-machines and the level of reimbursement. RESULTS: 16 PET-institutions from 10 different countries answered. The relation of PET-institutions to inhabitants ranged from 1:500,000 (B) and 1:1,000,000 (D, A, CH) to approximately 1:4,000,000 (I, E, F, NL). In Belgium, the Netherlands, France, Great Britain, Italy, Finland, Switzerland, and Spain reimbursement was possible and a broad spectrum of indications was accepted, respectively. The reimbursement was not restricted to official indications. In Germany and Austria PET was not generally covered for the patients insured by the national health insurance. An annual sum of approximately 450,000 euro was granted to the recognized PET-institutions in Belgium and France. In Denmark the clinics and their PET-centres were owned by the government, PET was part of the clinical routine oncology. If PET was separately covered the average level of reimbursement for the whole-body PET using a full-ring detector was 1200 euro. The reimbursement of the coincidence-gammacamera differed from the "dedicated" PET in most European countries. CONCLUSION: In Europe there is an increasing tendency to cover the well documented PET indications in oncology.

Europe↗
PubMed2003

[Guideline for in vivo- and in vitro procedures for thyroid diseases (version 2)].

The version 2 of the guideline for diagnostic standards of thyroid disorders is an update of the guideline published in 1999 and describes standards of in vitro and in vivo procedures. The following statements are modified: In vitro procedures: When measurement of the TSH-receptor antibodies is indicated, the guideline recommends the use of a second generation assay (recombinant human TSH-receptor as antigen). The functional assay sensitivity for the measurement of thyroglobulin should reach a value < or =1 ng/ml. Molecular genetic tests (RET proto-oncogene) are indicated in patients with a newly diagnosed medullary thyroid cancer and in the relatives of patients with hereditary medullary thyroid cancer. In vivo procedures: The sonographic examination should use a probe with a frequency of at least 7.5 MHz. Indications for the thyroid scintigraphy: nodule size > or =1 cm in diameter, autonomous goitre/nodule with clinical or subclinical hyperthyroidism, necessity of a differentiation between Graves' disease and chronic lymphocytic thyroiditis, therapy control after a definitive treatment and - in individual cases - the follow-up of untreated autonomous nodules.

Autoantibodies↗
PubMed2003

[Procedure guideline for radioiodine test (version 2)].

The version 2 of the procedure guideline for radioiodine test is an update of the guideline published in 1999. The following statements were added or modified: The procedure guideline discusses the pros and cons of a single measurement or of repeated measurements of the iodine-131 uptake and their optimal timing. Different formulas are described when one, two or three values of the radioiodine kinetic are available. The probe with a sodium iodide crystal, alternative or additionally the gamma-camera using the ROI-technique are instrumentations for the measurement of iodine-131 uptake. A possible source of error is an inappropriate measurement (sonography) of the target volume. The patients' preparation includes the withdrawal of antithyroid drugs 2-3 days before radioiodine administration. The patient has to avoid iodine-containing medication and the possibility of additives of iodide in vitamin- or electrolyte-supplementation has to be considered.

Documentation↗
PubMed2003

[Procedure guideline for thyroid scintigraphy (version 2)].

The version 2 of the procedure guideline for thyroid scintigraphy is an update of the procedure guideline published in 1999. The procedure guideline considers the current amendment of legislative rules (Richtlinie Strahlenschutz in der Medizin 2002). Indication and use of radiopharmaceuticals have to be confirmed by the specialist in nuclear medicine. Activities of 75 MBq technetium-99m, respectively of 10 MBq iodine-123 should not be exceeded without an individual justification. The interpretation of the scintigraphy requires the knowledge of the patients' history, the palpation of the neck, the laboratory parameters, and of the sonography. The interpretation of the technetium-99m uptake requires the knowledge of TSH concentration.

Humans↗
PubMed2003

[Procedure guideline for iodine-131 whole-body scintigraphy for differentiated thyroid cancer (version 2)].

The version 2 of the procedure guideline for iodine-131 whole-body scintigraphy for differentiated thyroid cancer is an update of the procedure guideline published in 1999. The following statements are added or modified: The two alternatives of an endogenous TSH-stimulation by the withdrawal of the thyroidal hormone medication and of an exogenous TSH-stimulation by the injection of the recombinant human TSH (rhTSH) have an equal sensitivity for the diagnostic use of radioiodine and for the measurement of thyroglobulin. Image acquisition under rhTSH is obtained approximately 48 h after the radioiodine administration, while an interval of about 72 h is preferred under endogenous TSH-stimulation. If iodine-negative metastases are expected, the feasibility of scintigraphy using (99m)Tc sestamibi or preferably positron emission tomography using (18)F-fluorodeoxyglucose should be considered. The sensitivity of FDG-PET is increased by TSH-stimulation. Before planning the iodine-131 scintigraphy the patient has to avoid iodine-containing medication and the possibility of additives of iodine in vitamin- and electrolyte-supplementation has to be considered.

Diagnosis, Differential↗
PubMed2003

[PET with (18)F-fluorodeoxyglucose for staging of non-small cell lung cancer].

AIMS: To evaluate studies on the use of positron emission tomography with the glucose analog (18)F-fluoro-deoxyglucose (FDG-PET) for the preoperative staging of patients with non-small cell lung cancer (NSCLC) according to the criteria of evidence based medicine and to discuss the cost-effectiveness of the technique. METHODS: Clinical studies published between 1995 and 2002 on the preoperative staging of non-small cell lung cancer were used for this analysis. Studies that did not meet the criteria published by the European Agency for the Evaluation of Medicinal Products (EMEA) were excluded. The validity of the studies was evaluated by a standardized rating system developed by the Agency for Health Care Policy and Research (AHCPR). RESULTS: For the detection of mediastinal lymph node metastases the mean sensitivity and specificity of FDG-PET on a patient basis is 85% and 87% (16 studies, 1355 patients). In studies that compared FDG-PET and computed tomography (CT) the mean sensitivity of CT was 66% at a specificity of 71%. In the detection of distant metastases FDG-PET correctly changed the tumor stage in 18% of the patients when compared to CT based staging (10 studies, 1073 patients). Five cost effectiveness analyses from the USA, Japan, and Germany concluded that FDG-PET improves the outcome of treatment at reduced or only slightly increased overall costs. Improvement of patient outcome was also demonstrated in a randomized trial, which found that the risk of a futile thoracotomy was reduced by 51% (p=0.003) when FDG-PET was added to the preoperative staging. CONCLUSION: According to the criteria of the AHCPR the use of FDG-PET for detection of mediastinal lymph node and distant metastases is documented at a level of evidence Ia and Ib, respectively. Since systematic analyses also indicate a favorable cost-effectiveness ratio FDG-PET has to be considered as "strictly indicated" for the preoperative staging of non-small cell lung cancer.

Carcinoma, Non-Small-Cell Lung↗
PubMed2003

[18F-Fluorodeoxyglucose positron emission tomography in restaging of colorectal cancer].

UNLABELLED: AIM, METHOD: Recommendations for the use of FDG-PET in relapsed colorectal cancer and the decision of reimbursement should base on published studies and on their level of evidence. Therefore, the PET-studies published between 1997 and 2002 were graded by the bias-criteria, by two rating-systems and by two classification-systems for the level of evidence according to AHCPR (Agency for Health Care Policy and Research) and VHA (Veterans Health Administration). RESULTS: The recommendation for the use of PET in relapsed colorectal cancer reached the level IIa according to the AHCPR, corresponding to level B according to the VHA. The sensitivity and specificity of FDG-PET were 94% (95% CI: 91-96%) and 78% (95% CI: 69-86%), respectively. Staging was changed correctly in 27% of patients (95% CI: 24-30%). Staging by FDG-PET was incorrect in 4% of the patients (95% CI: 2-5%) compared with the conventional methods. The additional use of PET changed the prospectively defined management plan for 34% of patients (95% CI: 31-38%). Either potentially curative operations were initiated in case of resectable tumour or futile operations were cancelled in case of multiple metastases. CONCLUSION: The 3-year-survival-rate following surgery would have exceeded 70% if the selection of patients had included an additional PET-examination. The correct selection of patients is requested in the daily routine as well as in the clinical implementation of neoadjuvant therapies to prevent a selection-bias from a suboptimal restaging without PET.

Colorectal Neoplasms↗
PubMed2003

[Prevention, screening and therapy of thyroid diseases and their cost-effectiveness].

Cost-effectiveness analyses focused on benign thyroid diseases are under-represented in the literature. The calculation of costs per additionally gained life year is difficult: The benefit of prevention is shifted into the distant future. The influence of an untreated subclinical thyroid disease on life expectancy can only be demonstrated by a long-term follow-up and by epidemiological databases. Iodine supplementation and programs for the prevention of tobacco smoking (primary prevention) are very cost-effective. Smoking increases the risk both of multinodular goiter and of Graves' disease. Screening programs (secondary prevention) are discussed for the laboratory parameters thyrotropin (TSH), calcium and calcitonin. TSH testing seems to be very cost-effective for epidemiological considerations in a certain lifespan (newborn, pregnancy, postpartal, older persons, hospitalisation due to acute diseases) and in persons with previously elevated TPO-antibodies or TSH-values >2 mU/l, but dedicated cost-effectiveness analyses are lacking. On the other hand, the cost-effectiveness of a routine TSH testing beyond the age of 35 years has been shown by a high-quality decision analysis. Therapeutic strategies (tertiary prevention) aim at the avoidance of complications (atrial fibrillation, myocardial infarction, death for cardiac reasons) and of iatrogenic complications. Examples of a tertiary prevention are: firstly the definitive therapy of Graves' disease in patients who have an increased risk of relapse after antithyroid drugs (ATD), secondly the radioiodine therapy for subclinical hyperthyroidism and the radioiodine therapy of large goiters in older patients or in patients suffering from a relevant comorbidity. Cost-effectiveness analyses for different therapeutic strategies of Graves' disease were published using a lifelong time-horizon. The ablative radioiodine dose-regime is cost-effective as a first line therapy if the risk of relapse after ATD exceeds 60%.

Cost-Benefit Analysis↗
PubMed2002

Radioiodine therapy and thyrostatic drugs and iodine.

Radioiodine therapy is now the most common definite treatment for persistent hyperthyroidism. The outcome of radioiodine therapy depends mainly on the absorbed energy dose in the diseased thyroid tissue. The administered activity and the resulting target dose in the thyroid depend on both the biokinetics of radioiodine and the actual therapeutic effect of radioiodine in the thyroid. Thyrostatic drugs have a major influence on the kinetics of radioiodine in the thyroid and may additionally have a radioprotective effect. Pre-treatment with thyrostatic medication lowers the effective half-life and uptake of radioiodine. This can reduce the target dose in the thyroid and have a negative influence on the outcome of the therapy. Discontinuation of medication shortly before radioiodine administration can increase the absorbed energy dose in the thyroid without increasing the whole-body exposure to radiation as much as would a higher or second radioiodine administration. Furthermore, administration of non-radioactive iodine-127 2-3 days after radioiodine administration can also increase the effective half-life of radioiodine in the thyroid. Thus, improving the biokinetics of radioiodine will allow lower activities to be administered with lower effective doses to the rest of the body, while achieving an equally effective target dose in the thyroid.

Antithyroid Agents↗
PubMed2002

31P NMR spectroscopy of blood plasma: determination and quantification of phospholipid classes in patients with renal cell carcinoma.

Advanced renal cell carcinoma (RCC) has a poor prognosis and is characterized by an unpredictable clinical course. The aim of this study was to assess the systemic phospholipid distribution as a possible marker of tumor stage and tumor spread beyond the kidney. To this end, the effect of renal cell carcinoma (RCC) on phospholipid concentrations in blood plasma using 31P NMR spectroscopy was studied in: (a) 29 patients with RCC prior to nephrectomy; (b) 19 healthy volunteers; (c) three patients with other renal tumors (renal metastases of bronchial carcinoma and of renal pelvic carcinoma, and a benign renal tumor). Furthermore, the phospholipid concentrations of eight patients of group (a) were determined 6 months after nephrectomy, when they were in remission. We found considerable deviations in the concentrations of the lysophosphatidylcholines (LPC1, LPC2) in both male and female patients with RCC compared to healthy volunteers (male--LPC1 0.217+/-0.062 vs 0.297+/-0.049 mmol/l, LPC2 0.036+/-0.014 vs 0.068+/-0.024 mmol/l; female--LPC1 0.195+/-0.071 vs 0.296+/-0.044 mmol/l, LPC2 0.037+/-0.027 vs 0.044+/-0.014 mmol/l). In addition, female patients with RCC showed lower concentrations of phosphatidylcholines (PC; 1.409+/-0.268 vs 1.947+/-0.259 mmol/l). The low phospholipid concentrations normalized for patients in remission. Phospholipid concentrations were found to depend on tumor stage and metastatic spread. The deviations in phospholipid concentrations (LPC1, LPC2, PC) observed may be attributable to systemic effects caused by the tumor as well as changes in enzyme activities.

Adult↗
PubMed2002

[Body weight gain after radioiodine therapy in hyperthyroidism].

AIM: Analysis and follow up of body weight after radioiodine therapy (RITh) of hyperthyroidism, since excessive weight gain is a common complaint among these patients. METHODS: Therapy and body weight related data of 100 consecutive RITh-patients were retrospectively analysed from the time before up to three years after RITh. All patients suffered from hyperthyroidism (Graves' disease or autonomy), but were adjusted to euthyroid levels after RITh. Patients' data were compared to a control group of 48 euthyroid patients out of the same ambulance and during the same time scale. RESULTS: All patients (RITh and controls) gained weight over the time. There was no statistically significant difference in BMI development over three years between RITh-patients and controls (5.5% resp. 4.9% increase). In the first year after RITh, weight gain of the RITh patients was higher indeed, but lower in the follow up, resulting in the same range of weight gain after three years as the controls. Besides that women showed a slightly higher increase of BMI than men, and so did younger patients compared to elder as well as patients with overweight already before RITh. CONCLUSIONS: An initially distinct increase of body weight after RITh of hyperthyroidism is mainly a compensation of pretherapeutic weight loss due to hyperthyroidism. Presupposing adequate euthyroid adjustment of thyroid metabolism after therapy, RITh is not responsible for later weight gain and adipositas.

Adult↗