[Guidelines for radiosynorviorthesis].
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Brachytherapy↗
Biomedical subjects
C Reiners
Publications and source records attributed to C Reiners.
Is the UICC/AJCC classification of primary tumor in childhood thyroid carcinoma valid?
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Adolescent↗
Clinical experience with recombinant human thyroid-stimulating hormone (rhTSH): whole-body scanning with iodine-131.
Whole-body scanning (WBS) with iodine-131 (I-131) is currently used together with serum thyroglobulin (Tg) measurement in the diagnostic follow-up of well-differentiated thyroid carcinoma. One of the main disadvantages of I-131 WBS is its requirement of repeated weeks-long withdrawal of thyroid hormone suppression therapy (THST) to raise endogenous thyroid-stimulating hormone (TSH) production. This results in hypothyroidism and associated abnormalities, discomfort and morbidity. Recently, however, a series of multicentre clinical studies established the efficacy, safety, non-antigenicity, and quality of life benefits of recombinant human TSH (rhTSH, Thyrogen, thyrotropin alfa, Genzyme Corporation, Cambridge, MA, USA) in promoting radioiodine uptake and permitting sensitive I-131 WBS in patients on THST after initial therapy of well-differentiated thyroid cancer. Thus in everyday practice, rhTSH administration may in many cases supersede THST withdrawal as a preparative method for I-131 imaging. With the use of rhTSH, as whenever I-131 WBS is performed, useful and accurate imaging requires meticulous attention to good scanning practices. These include use of appropriate equipment, proper timing, sufficient scanning time, vigilance against artifacts and iodine contamination, and consideration of additional imaging in the case of ambiguous 48-hour scans. Whole-body retention of I-131 is approximately 50% greater during hypothyroidism after THST withdrawal than during euthyroidism on THST and rhTSH. Therefore, it is important to use an adequate diagnostic activity of > or =4 mCi (148 MBq) to compensate for the faster radioiodine clearance in the euthyroid state permitted by rhTSH administration. Ongoing dosimetric research eventually may provide more specific guidance regarding radioiodine activities for diagnostic, and, particularly, therapeutic purposes, with the use of rhTSH.
Clinical Trials, Phase II as Topic↗
The role of recombinant thyroid-stimulating hormone (rhTSH) in the detection and management of well-differentiated thyroid carcinoma: a roundtable discussion.
A Roundtable meeting of European endocrinologists and nuclear medicine physicians recently examined the role of recombinant human thyroid-stimulating hormone (rhTSH, Thyrogen, thyrotropin alfa, Genzyme Corporation, Cambridge, MA, USA) in the detection and management of well-differentiated thyroid carcinoma. The meeting sought to review clinical work to date and to provide guidance and perspective on the agent's application in everyday practice. The Roundtable included a panel discussion centering on three major topics: 1) rationale for use of exogenous versus endogenous TSH stimulation of radioiodine uptake and thyroglobulin (Tg) production; 2) impact and use of rhTSH in diagnostic follow-up; and 3) role of rhTSH in radioablation. The panel concluded that obtaining TSH stimulation of radioiodine uptake and Tg production exogenously with rhTSH obviates the weeks-long withdrawal from thyroid hormone suppression therapy (THST) needed to obtain such stimulation endogenously. rhTSH administration thereby eliminates morbidity, discomfort and uncertainties of compliance and timing associated with THST withdrawal. Thus compared to withdrawal, rhTSH administration offers important advantages in safety, quality of life, reliability, predictability and convenience to patients and care providers. rhTSH therefore represents a major advance in the diagnostic follow-up of well-differentiated thyroid cancer. By increasing the sensitivity of serum Tg testing during THST, rhTSH administration also improves the sensitivity of diagnostic follow-up. In addition, heightening the sensitivity of Tg testing may permit more selective application of iodine-131 whole body scanning, decreasing the invasiveness of diagnostic follow-up. Clinical studies are underway to confirm the preliminary promise of rhTSH as an adjunct to radioablation of normal or neoplastic thyroid tissue, with emphasis on the therapeutic setting.
Antithyroid Agents↗
131I therapy of thyroid cancer patients.
Thyroid cancer is a rare malignancy with wide interethnic and geographic variations. In Germany thyroid carcinoma is the 13th most frequent malignancy (2.7 new cases yearly per 100,000 inhabitants). The overall temporal incidence is increasing slightly in recent years. The most common types of cancer are papillary (60-80%) and follicular cancers (10-20%). The relevant prognostic indicators are tumor stage and distant metastases. The mean survival rates in papillary thyroid cancer usually exceed 90%, whereas in follicular thyroid cancer they amount to approximately 80%. The standard treatment procedure in differentiated papillary and follicular thyroid cancer consists of total thyroidectomy followed by adjuvant ablative therapy with radioiodine. Only in papillary thyroid cancer stage pT1N0M0 lobectomy alone is considered to be appropriate. In patients with locally invasive differentiated thyroid cancers stage pT4 adjuvant percutaneous radiation therapy is a treatment option. Radioiodine therapy has to be performed under the stimulative influence of TSH. Usually TSH suppressive medication with Levothyroxine has to be withdrawn approximately 4 weeks prior to radioiodine therapy. In the future, exogenous stimulation by recombinant TSH may be used instead of thyroid hormone withdrawal. It has been proven by different studies that ablative radioiodine therapy reduces the frequency of recurrences and tumor spread in patients with thyroid cancer significantly. In patients with distant metastases, up to 50% of complete responses may be achieved with radioiodine treatment.
Adenocarcinoma, Follicular↗
Comparison of total and regional body composition in adolescent patients with anorexia nervosa and pair-matched controls.
Body composition in 31 adolescent girls suffering from anorexia nervosa (AN) was measured at the time of hospitalization in order to assess the muscle/bone relationship as a potential source of the development of osteopenia. Differences in lean tissue, fat and bone mass in total body, weight bearing and non weight bearing limbs were estimated in AN and pair-matched controls aged 14.2 +/- 1.8 years (range: 9-17 years). Further, it was investigated if bone mineral density (BMD) better reflects the muscle/bone relationship than bone mineral content (BMC). At the distal radius parameters measured by peripheral quantitative computed tomography (pQCT) were used to estimate the association of volumetric bone density to bone strength and lean body mass. The correspondence to the same and different body regions was assessed. Total lean mass in the controls was closely related to total body bone mineral content (TBBMC), as was lean tissue and bone mass of the limb subregions (r = 0.82 to 0.93). In contrast, the correlation was significantly lower in AN (r = 0.33 to 0.77). In the controls, the pQCT-derived bone strength was correlated with muscle mass of the forearm (r = 0.78, p < 0.001), but only moderately in AN (r = 0.47, n.s.). Regional lean tissue was 11-20% and fat mass was 56-66% lower in AN (p < 0.01). After adjustment for height, TBBMC was different at p = 0.01. Within the limbs subregions, BMC (but not BMD) was different in both groups only in the upper arm and the thigh. BMC reflected the bone/muscle relationship better than BMD. Intra- and between group regressions gave no significant differences between weight bearing and non weight bearing limbs. In conclusion, the assessment of musculoskeletal factors may be a useful tool to develop individual preventive measures for therapy after recovery of our patients.
Adolescent↗
[Sequelae of Czernobyl].
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Adenocarcinoma, Papillary↗
Redifferentiation therapy with retinoids: therapeutic option for advanced follicular and papillary thyroid carcinoma.
During the course of tumor progression the differentiated morphologic and functional characteristics of differentiated thyroid carcinomas (DTC) disappear. This corresponds to more aggressive growth, metastatic spread, and loss of iodine uptake. Experimental data give strong evidence that differentiated functions of iodine metabolism can be reinduced by retinoic acids. Results of a study performed in patients with advanced DTC are presented. Twenty patients with DTC (eight follicular, seven papillary, five oxyphilic) were selected for treatment with retinoic acid 1.5 mg/kg body weight/day over 5 weeks. All patients had advanced tumor stages with prior operative and radioiodine treatment. Extensive tumor invasion, distant metastatic spread, or insufficient or no radioiodine uptake precluded any conventional therapeutic option. The aim was to assess the changes under retinoid treatment. Iodine uptake increased in eight patients (three follicular, three papillary, two oxyphilic). Thyroglobulin (TG) as parameter for tumor mass and differentiation increased in 12 (63%) patients, decreased in 6 (32%), and did not change in 1 (5%). Retinoids do have an effect on differentiation status of DTC, reinducing iodine uptake in 50% of patients. TG levels do not always parallel a response in iodine uptake.
Adenocarcinoma, Follicular↗
Differentiated thyroid cancer in children and adolescents.
INTRODUCTION: There have been only a few studies on differentiated childhood thyroid cancer (DTC) in children and adolescents. METHODS: We analyzed the characteristics of DTC with respect to age, gender and histology in 114 patients under 18 years of age. In a questionnaire-based survey, data of 114 patients, aged between 3 years and 18 years, was collected from 65 clinical institutions in Germany. Characteristics of 80 females and 34 males were evaluated, and the prognostic effect of age, gender, histology, multicentric growth, tumor stage and N-status on distant metastases was tested using multivariate discriminant analysis. Between-group comparison was performed using student t-test and chi-squared test. RESULTS: The incidence of DTC in females was higher than in males with a peak of female:male ratio at puberty, which was more pronounced in children with papillary thyroid cancer, but not with follicular thyroid cancer. Papillary thyroid cancer was associated with more advanced disease (P=0.009), more lymph-node involvement (P=0.007) and more distant metastases (P=0.02) compared with follicular thyroid cancer. Multivariate analysis showed advanced tumor stage as the only significant factor (P=0.02) associating with distant metastasis. CONCLUSION: It can be concluded that in children and adolescents: 1. The incidence of papillary thyroid cancer is higher in females than males, with a peak at puberty. 2. The only significant factor associated with distant metastases is the advanced tumor stage. 3. Childhood thyroid cancer is frequently associated with lymph-node involvement, distant metastases and advanced tumor stage. 4. Papillary childhood thyroid cancer is more aggressive than follicular type.
Adenocarcinoma, Follicular↗
Five-year study of medical or surgical treatment in children with severe vesico-ureteral reflux dimercaptosuccinic acid findings. International Reflux Study Group in Europe.
UNLABELLED: The results of serial dimercaptosuccinic acid (DMSA) imaging over 5 years are reported in 287 children with severe vesico-ureteral reflux entered into the European Branch of the International Reflux Study in Children. The children were randomly allocated to medical (n=147) or surgical (n=140) management and DMSA studies were performed during the follow up period at least 6 months after any urinary tract infection. Abnormal images were classified into four types: (1) large polar hypodensity with normal renal outline; (2) peripheral photon deficient defect(s) in a non-deformed kidney; (3) small renal image with normal contour; and (4) peripheral defect(s) with resultant irregularity of the renal outline. The DMSA findings were abnormal at entry in 235 (82%) with no difference in incidence or severity between the two treatment groups. During follow up, deterioration was observed in 25 medically and 23 surgically treated patients and comprised image deterioration alone in 17, image deterioration with corresponding reduction in differential function in 16 and reduction in relative function without image change in 15, with similar distribution between the two treatment groups. Deterioration was more frequent in children entering the study under the age of 2 years and in those with grade IV rather than grade III reflux. These findings, showing no difference in outcome between children managed surgically or medically, are consistent with the radiological results already published. CONCLUSION: In the International Reflux Study the DMSA scintigraphic data showed no difference in outcome between children managed surgically or medically.
Child↗
Total body mineral mass versus total fat mass.
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Absorptiometry, Photon↗
Rapid urinary iodide test.
Assessment of iodine deficiency and monitoring of iodine supplementation programs demands rapid, simple and cost-effective methods for the determination of urinary iodide concentrations. We propose a rapid test based on the iodide-catalyzed oxidation of 3,3',5,5'-tetramethylbenzidine by peracetic acid/H2O2 to yield colored products. The color of the chemical reaction is compared with color categories of a pictogram corresponding to three ranges (<10, 10-30, and >>30 microg/100 mL) of iodide concentrations. The test is very easy to perform and does not require any instrumentation or apparatus. Sample preparation is simple and consists in the removal of interfering substances by disposable columns, 65 x 10.5 mm, packed with specifically prepared activated charcoal. For comparison with a reference method for measuring urinary iodide (HPLC), we determined the iodide concentrations of 370 random (untimed) urine samples from consecutive patients by both HPLC and the rapid test. The results obtained by both methods are in close agreement with respect to classification of the samples according to the above three ranges, with a maximum difference of <5% for each range. This rapid test is therefore very well suited to epidemiological surveys of iodine deficiency especially in developing countries.
Benzidines↗
Methodological and analytical aspects of simple methods for measuring iodine in urine. Comparison with HPLC and Technicon Autoanalyzer II.
This work describes an optimization of a simple photometric determination of iodine concentrations in urine using a modified ceric arsenite method with ammonium persulfate as oxidant. By means of this sensitive method iodine concentrations can be determined in very small specimens (50 microL). Urine samples (105) collected from a mixed population, were analyzed for urine iodine content by the optimized ammonium persulfate method, a Technicon Autoanalyzer II and a paired-ion-RP HPLC. We found that the precision of this optimized ammonium persulfate method yields inter assay CVs of <10% for urinary iodine concentrations >10 microg/dL. Recovery of [123I]iodide added to urine in vitro was 100.9 +/- 2.4%. The detection limit was 0.0029 microg iodine. There was a high correlation between all three methods (r > 0.94 in any case) and the interpretation of the results was consistent. We conclude that this simple, manual ammonium persulfate method is suitable for urinary iodine analysis and can be performed in any routine clinical laboratory.
Ammonium Sulfate↗
X-ray fluorescence analysis (XFA) of thyroidal iodine content (TIC) with an improved measuring system.
X-ray fluorescence analysis is based on the principal that the electron structure of stable iodine in the thyroid is excited by Americium-241 gamma rays to emit a characteristic fluorescence radiation which is proportional to the amount of iodine present in the gland. A stationary measuring system consisting of a 11.1 GBq Am-241 source and a high-purity Germanium detector with spectrum analyser has been improved by a PC guided method for sonographic definition of the measuring volume. The lower limit of detectibility of the system corresponds to 0.01 mg of Iodine per ml of thyroid volume; the in vivo precision given as coefficient of variation amounts to 15%. The thyroid is exposed with a radiation dose of 6 microSv per measurement. First studies with this improved system carried out in 50 female volunteers between 20 and 40 years of age with normal thyroid volumes resulted in a mean iodine concentration of the thyroid of 0.665 +/- 0.304 mg/ml. The mean iodine excretion in urine was normal with 10.8 +/- 10.4 microg/dl.
Adult↗
Methods for measuring iodine in urine and serum.
The most important information in the determination of the status of iodine nutrition of a population comes from the measurement of the urinary excretion of iodine. Several methods are available for measuring urinary iodine. The choice among methods depends on the intended application, the number of samples, the cost and the technical capability. Epidemiological field studies demand simple, rapid and cost-effective methods. Suitable for these applications are the rapid urinary iodide test and the ammonium persulfate oxidation method which gives comparable results to the chloric acid method without having the drawbacks of being hazardous and explosive. In research studies however, sophisticated automated technology like the Technicon Autoanalyzer or Paired-Ion Reversed Phase HPLC are used in which the high cost of instrumentation are outweighed by the benefits of processing a large number of samples with high accuracy and minimal technician time. For determining serum inorganic iodide (SII) the HPLC assay is the method of choice, because contaminations from the protein bound iodine fraction do not interfere with the detection process. The clinical relevance of the measurement of SII is limited, but allows the calculation of the absolute iodine uptake which has great value in pathophysiologic studies.
Ammonium Sulfate↗
Clinical evaluation of a high-resolution new peripheral quantitative computerized tomography (pQCT) scanner for the bone densitometry at the lower limbs.
Precision, long-term stability, linearity and accuracy of the x-ray peripheral quantitative computerized tomographic (pQCT) bone scanner XCT 3000 (Norland-Stratec Medical Sys.) were evaluated using the European Forearm Phantom (EFP). In vivo measurements were assessed using a standardized procedure at the distal femur and the distal tibia. In the patient-scan mode, the spatial resolution of the system was 1.04 +/- 0.05 lp/mm as measured at the 10% level of the modulation transfer function (MTF). The contrast-detail diagram (CDD) yielded a minimal difference in attenuation coefficient (AC) of 0.07 cm(-1) at an object size of 0.5 mm. The effective dose for humans was calculated to be less than 1.5 microSv per scan. Short-term precision in vivo was expressed as root mean square standard deviation of paired measurements of 20 healthy volunteers (RMSSD = 0.5%). At the distal femur total volumetric density (ToD) and total cross-sectional area (ToA) were found to be less sensitive to positioning errors than at the distal tibia. Structural parameters like the polar cross-sectional moment of inertia (CSMIp) or the polar cross-sectional moment of resistance (CSMRp) showed a good short-term precision at the distal femur (RMSSD = 1.2 and 1.4%). The relation between the two skeletal sites with respect to CSMIp or CSMRp showed a high coefficient of determination (r2 = 0.77 and 0.74).
Bone Density↗
Reverse transcriptase-polymerase chain reaction analysis of thyrocyte-relevant genes in fine-needle aspiration biopsies of the human thyroid.
Currently, fine-needle aspiration cytology is a valuable tool in the routine diagnosis of suspicious thyroid nodules. We present a very sensitive method for the molecular analysis of the expression of several genes important for normal thyroid function in parallel to the cytological diagnosis. We adapted reverse transcriptase polymerase chain reaction (RT-PCR) to amplify thyroid-typical mRNAs in samples of thyroid carcinoma cells as small as those obtained by fine-needle aspiration biopsy (FNAB), ie, 100-1000 cells, and applied this procedure to four routinely taken FNABs. Gene products such as thyroglobulin (Tg), thyroid-stimulating hormone-receptor (TSHr), sodium/iodide-symporter (NIS), type I iodothyronine-5'-deiodinase (DI), and type II iodothyronine-5'-deiodinase (DII) were analyzed. To establish RT-PCR protocols, serial dilutions of follicular thyroid carcinoma cells, FTC-133, which express these genes at low levels, were initially used for RNA isolation. Successful RNA isolation and reverse transcription were checked by the amplification of beta-actin mRNA. We detected the mRNAs coding for Tg in as little as 10 cells, for NIS in 100 cells, and for TSHr, DI, and DII in 10,000 cells. After preparing cytological smears of four routinely taken FNABs, all above-mentioned thyroid-typical mRNAs were observed by using the material remaining in the needle for RNA isolation followed by RT-PCR. This method offers the possibility of obtaining two different types of information from the same routinely taken thyroid FNAB: the cytological diagnosis and the expression pattern of several diagnostically relevant genes. Therefore, a more specific diagnosis could be rendered in the preoperative state, and may lead to more specific therapy.
Biopsy, Needle↗
Influences on evaluability of radionuclide ventriculography in chemotherapy patients.
Radionuclide ventriculography (RNV) is an established method of evaluating cardiotoxic side-effects of chemotherapy. The image quality of RNV depends on labelling yields obtained after red blood cell (RBC) labelling with 99Tc(m)-pertechnetate and has an influence on the evaluation of the left ventricular ejection fraction (LVEF). Several drugs and certain parameters of RBC labelling are known to have a detrimental effect on the labelling yield, but often the reason for poor image quality remains unclear. The aim of this study was to determine the effect of chemotherapeutic agents on LVEF evaluation. The chemotherapeutic medications and RNV data of 116 patients were noted. The patients underwent 205 RNV examinations (up to 7 RNV follow-up examinations) consisting of rest and stress studies. Ten patients with a poor labelling yield after in vivo labelling received an additional RNV study after in vitro labelling. The effects of commonly used anticoagulants and chemotherapeutic drugs on labelling yields were also investigated in experiments on in vitro RBC labelling. In vitro labelling had the advantage of better detection of pathological alterations in left ventricular motility, but often improved evaluability only slightly. The administration of corticosteroids showed an unexpected positive correlation with image quality (Spearman correlation coefficient: prednisone, 0.42403, P = 0.0013; prednisolone, 0.45629, P = 0.0286) and labelling yield (prednisolone, 0.65466, P = 0.0024), whereas idarubicin showed a negative correlation with image quality (-0.53364, P = 0.005). A slight positive correlation of prednisolone with LVEF at rest (0.45425, P = 0.0197) was also noted. Using our evaluation software, the manual contour method was found to be superior to the automatic determination of the left ventricular contour. Cycle ergometry alone caused a significant deterioration in image quality. The in vitro results suggested a negative influence of epirubicine on labelling yields at very high concentrations (10(-3) M). Our main result was that a clinically adequate study is possible in patients with moderate image quality and labelling yields. Furthermore, the administration of corticosteroids had a positive impact on image quality.
Adult↗