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M Dietlein

Publications and source records attributed to M Dietlein.

At least 19 recordsLinked to original sources
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↗
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

[Graves' disease nd toxic nodular goiter--radioiodine therapy].

At the 15th conference on the human thyroid in Heidelberg in 2001 the following aspects of the radioiodine therapy of benign thyroid disorders were presented: General strategies for therapy of benign thyroid diseases, criterions for conservative or definitive treatment of hyperthyroidism as first line therapy and finally preparation, procedural details, results, side effects, costs and follow-up care of radioiodine therapy as well as legal guidelines for hospitalization in Germany. The diagnosis Graves' hyperthyroidism needs the decision, if rather a conservative treatment or if primary radioiodine therapy is the best therapeutic approach. In the USA 70-90% of these patients are treated with radioiodine as first line therapy, whereas in Germany the conservative therapy for 1-1.5 years is recommended for 90%. This review describes subgroups of patients with Graves' disease showing a higher probability to relapse after conservative treatment. Comparing benefits, adverse effects, costs, and conveniences of both treatment strategies the authors conclude that radioiodine therapy should be preferred as first line therapy in 60-70% of the patients with Graves' hyperthyroidism.

Germany↗
PubMed2002

[Assessment of endocrine disorders of the hypothalamic-pituitary axis by nuclear medicine techniques].

The following article reviews nuclear medicine techniques which can be used for assessment of endocrine disorders of the hypothalamic-pituitary axis. For planar and SPECT imaging somatostatin-receptor- and dopamine-D2-receptor-scintigraphy are the most widely distributed techniques. These nuclear medicine techniques may be indicated in selected cases to answer differential diagnostic problems. They can be helpful to search for presence and localization of receptor positive tissue. Furthermore they can detect metastasis in the rare cases of a pituitary carcinoma. Scintigraphy with Gallium-67 is suitable for further diagnostic evaluation in suspected hypophysitis. Other SPECT radiopharmaca do not have relevant clinical significance. F-18-FDG as PET radiopharmacon is not ideal because obvious pituitary adenomas could not be visualized. Other PET radiopharmaca including C-11-methionine, C-11-tyrosine, F-18-fluoroethylspiperone, C-11-methylspiperone, and C-11-raclopride are available in specialized centers only. Overall indications for nuclear medicine in studies for the assessment of endocrine disorders of the hypothalamic-pituitary-axis are rare. Original studies often report only about a small number of patients. According to the authors' opinion the relevance of nuclear medicine in studies of clinically important endocrinologic fields, e.g. localization of small ACTH-producing pituitary adenomas, tumor localization in ectopic ACTH syndrome, localization of recurrent pituitary tissue, assessment of small incidentalomas, can not be definitely given yet.

Humans↗
PubMed2001

Whole-body positron emission tomography using 18F-fluorodeoxyglucose for initial staging of patients with Hodgkin's disease.

An accurate initial staging of patients with Hodgkin's disease (HD) is important for the evaluation of clinical stage and risk factors, which are crucial for the choice of an appropriate treatment. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is useful for detecting active tumor tissue in patients with lymphoproliferative diseases and may contribute to conventional staging methods in patients with HD. Twenty-two patients who presented with newly diagnosed HD underwent conventional staging methods including computed tomography (CT) as well as FDG PET. Lesions apparent in FDG PET and CT were correlated to each other. Seventy-seven lesions were observed either in PET or CT or in both. In 48 (62%) lesions PET and CT were both positive. In 20 (26%) sites, PET was positive and CT negative. Of 22 patients (18%) 4 were upstaged due to these positive PET findings, and as a result one patient received a different therapeutic regimen. PET failed to detect nine (12%) CT-positive sites in six patients. Statistically, these data are reflected by a sensitivity for PET and CT of 88% and 74%, respectively. Specificity of both imaging modalities was 100%. PET can contribute valuable information as an additional staging examination and led to an upstaging in some patients with primary HD. However, PET should not be used as the only imaging modality as it failed to detect CT-positive, active tumor regions in some cases.

Adult↗
PubMed2001

Thoracic positron emission tomography using 18F-fluorodeoxyglucose for the evaluation of residual mediastinal Hodgkin disease.

Residual mediastinal masses are frequently observed in patients with Hodgkin disease (HD) after completed therapy, and the discrimination between active tumor tissue and fibrotic residues remains a clinical challenge. We studied the diagnostic value of metabolic imaging by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in detecting active mediastinal disease and predicting relapse. Twenty-eight HD patients with a residual mediastinal mass of at least 2 cm after initial therapy or after salvage chemotherapy were prospectively assigned to 29 examinations with FDG PET and were evaluated as 29 "subjects." Patients were monitored for at least 1 year after examination and observed for signs of relapse. Median follow-up was 28 months (range, 16 to 68 months). A PET-negative mediastinal tumor was observed in 19 subjects, of whom 16 stayed in remission and 3 relapsed. Progression or relapse occurred in 6 of 10 subjects with a positive PET, whereas 4 subjects remained in remission. The negative predictive value (negative PET result and remission) at 1 year was 95%, and the positive predictive value (positive PET result and relapse) was 60%. The disease-free survival for PET-negative and PET-positive patients at 1 year was 95% and 40%, respectively. The difference was statistically significant. A negative FDG PET indicates that an HD patient with a residual mediastinal mass is unlikely to relapse before 1 year, if ever. On the other hand, a positive PET result indicates a significantly higher risk of relapse and demands further diagnostic procedures and a closer follow-up.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Non-Q-wave myocardial infarction: impaired myocardial energy metabolism in regions with reduced 99mTc-MIBI accumulation.

Reduced regional technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) accumulation in patients with chronic non-Q-wave infarction (NQWI) but without significant coronary artery stenosis indicates non-transmural damage of the myocardial wall. The aim of this study was to characterise cardiac energy metabolism after NQWI using phosphorus-31 magnetic resonance spectroscopy (31P-MRS) and to compare the biochemical remodelling with changes in regional 99mTc-MIBI uptake and with morphological and functional parameters assessed by magnetic resonance imaging (MRI). Fifteen patients with a history of NQWI, exclusion of significant coronary artery stenosis (<50% diameter stenosis) and hypokinesia of the anterior wall (group A) were examined with 31P-MRS to study the effects of NQWI on myocardial energy metabolism. Spectroscopic measurements were performed in the infarct-related myocardial region. Corresponding gradient-echo MR images and myocardial 99mTc-MIBI single-photon emission tomography images were acquired for exact localisation of the infarct region. All examinations were performed at rest under anti-ischaemic medication. Data were compared with those of patients in whom coronary artery disease had been excluded by angiography (group B, n=10). All patients of group A displayed anterior wall hypokinesia in the infarcted area on both ventriculography and MRI, with a reduced myocardial accumulation of 99mTc-MIBI (66.3%+/-11.8% vs 95.6%+/-2.2% in group B). The mean wall thickness during the complete cardiac cycle (9.5+/-1.8 mm vs 13.1+/-1.1 mm in group B, P<0.001), the systolic wall thickening (2.6+/-1.4 mm vs 5.8+/-1.5 mm in group B, P<0.01) and the phosphocreatine/adenosine triphosphate ratio (1.12+/-0.22 vs 1.74+/-0.23 in group B, P<0.01) in the hypokinetic area were all significantly reduced. It is concluded that persisting hypokinetic myocardium after NQWI combined with reduced myocellular uptake of 99mTc-MIBI displays a reduced PCr/ATP ratio. Our results indicate that morphological remodelling after NQWI is accompanied by fundamental changes in cardiac energy metabolism.

Adenosine Triphosphate↗