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Purpose: To assess dose levels in routine nuclear medicine (NUC) procedures in Austria as a prior to a legislative update of the National Diagnostic Reference Levels (NDRL)., Method: As part of a nationwide survey of common NUC-examinations between June 2019 and November 2019, data sets were collected from 33 Austrian hospitals with NUC equipment. All hospitals were asked to report the NUC imaging devices in use (model, type, year of manufacture, detector material, collimators), the standard protocol parameters for selected examinations (standard activity, collimator, average acquisition time, reconstruction type, use of time-of-flight) and to report data from 10 representative examinations (e.g. injected activity, weight), incl. the most common NUC-examinations for planar imaging/SPECT and PET. Median/mean values for injected activity were calculated and compared to current Austrian and international NDRL. A Pearson correlation coefficient was computed comparing different variables., Results: In total, all 33 hospitals (100% response rate) reported data for this study for 60 SPECT devices, 21 PET/CT devices and 23 scintigraphy devices. Fixed activity values for scintigraphy/SPECT and PET were employed by about 90% and 56% of the hospitals, respectively. The most widely performed examinations for scintigraphy/SPECT are bone imaging, thyroid imaging, renal imaging (with MAG3/EC) and lung perfusion imaging (in 88% of the hospitals) and F-18 FDG-PET studies for oncology indications (in 100% of the hospitals). Significant correlations were found for patient weight and injected activity (scintigraphy/SPECT), use of iterative reconstruction and injected activity (PET) as well as size of field-of-view and injected activity (PET)., Conclusions: The reported injected activity levels were comparable to those in other countries. However, for procedures for which NDRL exist, deviations in injected activities of >20% compared to the NDRL were found. These deviations are assumed to result mainly from advances in technology but also from deviations between NDRL and prescribed activities as given in the information leaflets of the radiopharmaceuticals., (Copyright © 2021. Published by Elsevier GmbH.)

Background: We aimed to compare the established metabolic response criteria PERCIST and EORTC for their applicability and predictive value in terms of clinical response assessment early after the initiation of lenvatinib therapy in patients with metastatic radioiodine-refractory (RAI) thyroid cancer (TC). Methods: In 25 patients treated with lenvatinib, baseline and 4-month follow-up F-18 FDG PET/CT images were analyzed using PERCIST 1.0, modified PERCIST (using SUVpeak or SUVmax) and EORTC criteria. Two groups were defined: disease control (DC) and progressive disease (PD), which were correlated with PFS and OS. Results: PERCIST, mPERCIST, PERCISTmax and EORTC could be applied in 80%, 80%, 88% and 100% of the patients based on the requirements of lesion assessment criteria, respectively. With PERCIST, mPERCIST, PERCISTmax and EORTC, the patients classified as DC and PD ranged from 65 to 68% and from 32 to 35%, respectively. Patients with DC exhibited a longer median PFS than patients with PD for EORTC (p < 0.014) and for PERCIST and mPERCIST (p = 0.037), respectively. Conclusion: EORTC and the different PERCIST criteria performed equally regarding the identification of patients with PD requiring treatment changes. However, the applicability of PERCIST 1.0 using SULpeak seems restricted due to the significant proportion of small tumor lesions.

Background: Lenvatinib has proven efficacy in progressive, radioiodine- (RAI-) refractory thyroid cancer (TC). Dose reductions are commonly performed due to decreased tolerability and adverse effects. This retrospective multicenter study analyzed overall survival (OS) and progression-free survival (PFS) and tolerability in the Austrian patient population treated with lenvatinib., Methods: Clinical data of 43 patients (25 males and 18 females) with a median age of 70 years (range: 39-91 years) and RAI-refractory TC with metastases to the lymph nodes (74%), lungs (86%), bone (35%), liver (16%), and brain (12%) were analyzed. The mean duration of treatment with lenvatinib was 26.6 ± 15.4 months with dosage reductions required in 39 patients (91%)., Results: PFS after 24 months was 71% (95% CI: 56-87), and overall survival (OS) was 74% (95% CI: 60-88), respectively. OS was significantly shorter ( p =0.048) in patients with a daily maintenance dosage ≤ 10 mg (63%) (95% CI: 39-86) as compared to patients on ≥ 14 mg lenvatinib (82%) (95% CI: 66-98) daily. Dose reduction was noted in 39 patients (91%). Grade ≥3 toxicities (hypertension, diarrhea, weight loss, and palmar-plantar erythrodysesthesia syndrome) were most common leading to discontinuation of lenvatinib in 7 patients (16%)., Conclusion: Lenvatinib showed sustained clinical efficacy in patients with metastatic RAI-refractory TC even with reduced maintenance dosages over years. The effects were comparable to the registration trial, although patients had a higher median age and, more commonly, dose reductions., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 G. Rendl et al.)

Objective: To evaluate the diagnostic accuracy of a modified scrape cell block (SCB) technique in a large series of patients. The technique was especially developed and tested for fine-needle aspiration of thyroid and parathyroid nodules., Study Design: Eighty-two ultrasound-guided fine-needle aspiration specimens with the sonographic aspect of a thyroid (n = 33) or a possible parathyroid nodule (n = 49) were studied. Immunohistochemistry (IHC) was used on cell blocks containing plasma, thromboplastin, and selected 3-dimensional cell aggregates scraped off Papanicolaou-stained smears. Antibodies for chromogranin A, thyroglobulin, parathyroid hormone, calcitonin, and carcinoembryonic antibody (CEA) were used. In cases of reduced immunosensitivity or suspected metastases or rare primary tumors, additional IHC markers were employed., Results: Chromogranin A was expressed in all 28 parathyroid adenomas (PA), in 7 of 8 hyperplastic parathyroid glands, and in 13 of 14 medullary thyroid carcinomas (MTC). When combining positivity for chromogranin A and calcitonin/CEA, the specificity for the detection of MTC was 100%. Parathyroid hormone was expressed in 26 of 36 parathyroid nodules (72.2%). When combining follicular microarchitecture and expression of chromogranin A, the specificity for the detection of parathyroid tissue was 97%., Conclusion: With the modified SCB technique, accurate cytological diagnoses were obtained in 97.6% of 82 patients., (© 2016 S. Karger AG, Basel.)

Background: The purpose of the study is to evaluate the physical performance of a Biograph mCT Flow 64-4R PET/CT system (Siemens Healthcare, Germany) and to compare clinical image quality in step-and-shoot (SS) and continuous table motion (CTM) acquisitions., Methods: The spatial resolution, sensitivity, count rate curves, and Image Quality (IQ) parameters following the National Electrical Manufactures Association (NEMA) NU2-2012 standard were evaluated. For resolution measurements, an (18)F point source inside a glass capillary tube was used. Sensitivity measurements were based on a 70-cm-long polyethylene tube, filled with 4.5 MBq of FDG. Scatter fraction and count rates were measured using a 70-cm-long polyethylene cylinder with a diameter of 20 cm and a line source (1.04 GBq of FDG) inserted axially into the cylinder 4.5 cm off-centered. A NEMA IQ phantom containing six spheres (10- to 37-mm diameter) was used for the evaluation of the image quality. First, a single-bed scan was acquired (NEMA standard), followed by a two-bed scan (4 min each) of the IQ phantom with the image plane containing the spheres centered in the overlap region of the two bed positions. In addition, a scan of the same region in CTM mode was performed with a table speed of 0.6 mm/s. Furthermore, two patient scans were performed in CTM and SS mode. Image contrasts and patient images were compared between SS and CTM acquisitions., Results: Full Width Half Maximum (FWHM) of the spatial resolution ranged from 4.3 to 7.8 mm (radial distance 1 to 20 cm). The measured sensitivity was 9.6 kcps/MBq, both at the center of the FOV and 10 cm off-center. The measured noise equivalent count rate (NECR) peak was 185 kcps at 29.0 kBq/ml. The scatter fraction was 33.5 %. Image contrast recovery values (sphere-to-background of 8:1) were between 42 % (10-mm sphere) to 79 % (37-mm sphere). The background variability was between 2.1 and 5.3 % (SS) and between 2.4 and 6.9 % (CTM). No significant difference in image quality was observed between SS and CTM mode., Conclusions: The spatial resolution, sensitivity, scatter fraction, and count rates were in concordance with the published values for the predecessor system, the Biograph mCT. Contrast recovery values as well as image quality obtained in SS and CTM acquisition modes were similar.

Gastrointestinal stromal tumours (GISTs) are fairly rare neoplasms, constituting less than 3 % of all gastrointestinal malignancies. The integration of molecularly targeted treatment regimes (i.e., tyrosine kinase inhibitors) in clinical oncology has revolutionized the management of patients with irresectable GISTs or metastatic disease. Malignant GISTs usually display increased glucose metabolism and therefore (18)F-fluorodeoxyglucose (FDG) uptake within the scope of positron emission tomography (PET) scans. Nowadays, dual-modality FDG PET/CT (computed tomography) imaging is of considerable value in diagnostic work-up of patients with GISTs acquiring functional and anatomic information simultaneously. The following article sheds light on the impact of FDG PET and combined FDG PET/CT imaging in initial disease evaluation, detection of tumour recurrence and the early assessment of treatment response to molecularly targeted agents such as imatinib mesylate or sunitinib maleate.

Neuroendocrine tumors (NET) are, despite increasing incidence, still rare, usually slow growing neoplasms with resemblance to nerve cells and the endocrine capability of hormone production. In contrast to commonly used conventional imaging procedures, nuclear imaging is feasible to visualize the presence of molecular biomarkers, particularly the overexpression of somatostatin receptors (sstr) with high diagnostic accuracy which has led to the establishment of somatostatin receptor scintigraphy (SRS) as essential component and gold standard of functional imaging in the workup of NET. Another major feature is the selection of patients with inoperable or metastasized tumors showing sufficient uptake for peptide receptor radionuclide therapy (PRRT). While somatostatin receptor PET and PET/CT using Ga-68-labeled SSR analogs represents the consistent further development of SRS, FDG-PET can only be used in tumors with high proliferative activity but not on a routine basis for imaging of neuroendocrine tumors. (18)F-DOPA represents an alternative PET tracer worth mentioning currently under assessment for NET imaging.

Screening for thyroid dysfunction is recommended among certain groups of women, who plan a pregnancy, for example women with history of hyperthyroid or hypothyroid disease, with type 1 diabetes or other autoimmune disorders or women with previous therapeutic head or neck irradiation, in the case of infertility. Management of thyroid disease during pregnancy requires special consideration because pregnancy induces major changes in thyroid function, and maternal thyroid disease can have adverse affects on the pregnancy and the foetus. Under ideal conditions there is a cooperation among several healthcare professionals, such as endocrinologists, nuclear medicine physicians, gynaecologists, neonatologists and if necessary surgeons. This article surveys the physiological and pathological changes of thyroid, their diagnosis and therapy in the case of women in childbearing age, women with unfulfilled desire to have children, pregnant women, as well as women after delivery.

Purpose: The purpose of this prospective study was to determine the diagnostic impact and influence on patient treatment of posttherapeutic (131)I SPECT-CT when the findings on planar posttherapeutic whole-body scintigraphy (ptWBS) were inconclusive., Materials and Methods: A total of 53 SPECT-CT scans were performed in 41 patients with thyroid cancer after high-dose (131)I therapy (2.944 to 7.526 GBq (131)I) because of diagnostic uncertainty on ptWBS. Physiological uptake in the salivary glands, gastric mucosa, gut, nasal mucosa, urinary tract and liver were considered to be normal. Any other foci of increased (131)I uptake, except iodine uptake clearly located in the thyroid bed, were considered to be abnormal. The data were evaluated on a lesion and a patient basis., Results: Regarding neck lesions, SPECT-CT provided a diagnostic impact in 26/90 lesions (28.9%) and confirmed the diagnosis in 64/90 lesions (71.1%). On a patient basis, SPECT-CT changed N status in 12/33 patients (36.4%), provided a diagnostic impact in 21/33 patients (63.6%) and led to a treatment change in 8/33 patients (24.2%). Regarding lesions distant from the neck, SPECT-CT confirmed the diagnosis in 62/71 lesions (87.3%) and had a diagnostic impact in 9/71 lesions (12.7%). On a patient basis, SPECT-CT changed M status in 4/19 patients (21.1%), had a diagnostic impact in 14/19 patients (73.7%) and led to a treatment change in 2/19 patients (10.5%). Considering all patients, SPECT-CT led to a treatment change in 10/41 patients (24.4%)., Conclusion: Integrated SPECT-CT is a useful tool, especially in cases of diagnostic uncertainty and helps to individualize patient management.

Purpose: Patients with persistent elevated PSA and repeated negative prostate biopsy, that means having the prostate biopsied at multiple times, were investigated with 18F-choline PET/CT to delineate prostate cancer and guide renewed prostate biopsy., Methods: Twenty patients with elevated PSA and negative prostate biopsies underwent 18F-choline PET/CT. We performed an early examination of the pelvic region 3-5 min after application. After 30 minutes a whole body PET/CT examination was performed. Image analysis was performed visually and by semi-quantitative analysis calculating the maximum standardised uptake value (SUVmax). 18F-choline uptake was defined as focal, multifocal or inhomogeneous. After the 18F-choline PET/CT, all patients underwent a repeated prostate biopsy, and in the cases where a focal or multifocal uptake was found, the biopsy was guided by the result of the examination., Results: Qualitative image analysis revealed focal 18F-choline uptake in 13 out of 20 patients. In five patients, prostate cancer was revealed by repeated aspiration biopsy. None of the patients with a multifocal or inhomogeneous 18F-choline uptake had a malignant neoplasm in the prostate. Semiquantitative analysis performed with SUVmax was not helpful in the discrimination of malignancy but showed high values also in benign prostate diseases, as well as in normal prostate tissue. The dual-phase protocol delivered no clear benefit in discriminating malignancy from benign alterations., Conclusion: The use of 18F-choline cannot be generally recommended for localising prostate cancer; however, in highly selected patients, we found useful additional information. In 25% of patients, 18F-choline PET/CT allowed the identification of neoplastic prostatic zones.

Gaucher disease is the most prevalent inherited, lysosomal storage disease and is caused by deficient activity of the enzyme beta-glucocerebrosidase. Bone and bone marrow alterations are frequent in the most prevalent non-neuronopathic form of Gaucher disease. Imaging of bone manifestations in Gaucher disease is performed by a variety of imaging methods, conventional X-ray and MRI as the most frequently and most important ones. However, different modalities of scintigraphic imaging have also been used. This article gives an overview on scintigraphic imaging with respect to bone manifestations in Gaucher disease discussing the advantages and limitations of scintigraphic imaging in comparison to other imaging methods.

Background: Thyroid hormone administration is associated with low bone density in some studies. The aim of the present study was to evaluate the influence L-thyroxine, in doses used to treat patients with a history of thyroid carcinoma, on serum cathepsin K and other markers of bone metabolism. Cathepsin K is thought to have a role in osteoclast mediated bone resorption., Methods: A group of male patients with differentiated thyroid cancer (DTC) on suppressive L-thyroxine therapy (DTC-group; n = 51; mean age 57 years; TSH < 0.1 mU/L) was selected as a model for hyperthyroidism. The results were compared to a group of healthy euthyroid men (control-group; n = 50; mean age 58 years; TSH 1.5 +/- 0.9 mU/L)., Results: In the DTC-group the median value of cathepsin K was 6.9 pmol/L, in the control group 4.8 pmol/L (p = 0.0052; highly significant [h.s.]). There was a significant negative correlation of cathepsin K with age (r = -0.279, p = 0.028). The analysis of various bone associated parameters revealed an increase of serum crosslaps in the DTC-group versus euthyroid controls (p = 0.03). A significant correlation could be found for cathepsin K and osteoprotegerin (p = 0.002)., Conclusion: Cathepsin K is increased by a suppressive L-thyroxine therapy and decreases with increasing age. The increased cathepsin K levels seen in DTC-patients on suppressive L-thyroxine therapy are likely to contribute to accelerated bone degradation in these patients.

Purpose: 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a well-established method in the follow-up of patients with differentiated thyroid carcinoma (DTC), elevated thyroglobulin (Tg) and negative 131I scans. This retrospective clinical study was designed to evaluate the impact of computed tomography (CT) and that of FDG-PET in combined FDG-PET/CT examinations on the restaging of DTC patients., Methods: Forty-seven FDG-PET/CT scans of 33 patients with a history of DTC, elevated Tg levels and negative 131I uptake or additionally suspected 131I-negative lesions were studied. PET and CT images were analysed independently by an experienced nuclear medicine specialist and a radiologist. Afterwards a final consensus interpretation, the gold standard in our department, was provided for the fused PET/CT images and, if available, for supplementary investigations., Results: Thirty-five investigations (74%) revealed pathological FDG-PET/CT findings. In summary, 25 local recurrences, 62 lymph node metastases and 122 organ metastases (41 lung, 60 bone, 21 other organs) were diagnosed. In 36 out of 47 examinations (77%), the original PET diagnoses were modified in the final consensus interpretation owing to the CT assessments. In 8 of the 35 pathological FDG-PET/CT examinations (23%), the final consensus interpretation of the PET/CT images led to an alteration in the treatment plan., Conclusion: PET/CT is a powerful fusion of two pre-existing imaging modalities, which not only improves the diagnostic value in restaging DTC patients with elevated Tg and negative 131I scan, but also provides accurate information regarding subsequent treatment options and may lead to a change in treatment management.

Unlabelled: The AIM of this study was to determine the additional value of SPECT/CT in sentinel node scintigraphy in breast cancer. Furthermore, it was our question to determine, whether the low-dose computed tomography component (LD-CT) can be used for axillary lymph node staging of clinically negative patients., Patients, Methods: 51 patients with invasive breast cancer <3 cm in diameter were included in our prospective investigation. SPECT/CT was performed on a dedicated scanner 30 minutes after subareolar injection of (99m)Tc-Nanocoll. Axillary staging with CT(LD) was performed using standard CT-criteria. SLN were allocated to an axillary level using SPECT alone and SPECT/CT. Additionally, the number of SLN on CT(LD) corresponding to the scintigraphic hot node was notified for each patient and compared to the number of SLN found with the gamma probe., Results: In 45/51 evaluable patients SLN could be localised in level I in 43 patients and in level II in two patients (all positive) using SPECT-CT, whereas a clear allocation could not be obtained by SPECT alone. The number of SLN was discrepant between SPECT and CT(LD) in 13/45 patients. The number of SLN detected with the gamma probe (n = 68) not significantly differed from the number of SLN detected by CT(LD) (n = 65) but was significantly higher than with SPECT (n = 51). CT(LD) yielded a sensitivity of 35.7%, a specificity of 83.9%, a positive predictive value (PPT) of 50%, a negative predictive value (NPV) of 74.3% and a diagnostic accuracy of 68.9% for axillary staging with CT(LD)., Conclusion: The additional information of SPECT/CT allows a more accurate characterization of the SN concerning size, depth and anatomical location. CT(LD) when performed during (99m)Tc-Nanocoll sentinel-SPECT/CT is not suitable for axillary staging in breast cancer patients with clinical negative axilla due to its low sensitivity and moderate specificity. Therefore, it does not influence the decision for SNB or ALND. The limited resolution of SPECT leads to an underestimation of the number of SLN compared to CT(LD) and the gamma probe.

Introduction: The aim of our study was to determine whether treatment with a long-acting somatostatin-receptor analogue is effective in patients with (131)I-negative but somatostatin-receptor-positive metastases from dedifferentiated and anaplastic thyroid cancer., Materials and Methods: Twelve patients were screened for the study. All of them showed progressive disease confirmed by radiologic evaluation, increasing serum thyroglobulin (Tg), and negative diagnostic or posttherapeutic (131)I whole-body scans (WBS). Eight of 12 patients (4 males and 4 females; age range, 57-89 years; 1 papillary thyroid cancer; 4 poorly differentiated follicular thyroid cancer; 1 follicular and anaplastic thyroid cancer; 2 anaplastic thyroid cancer) showed positive somatosatin-receptor expression in Tc-99m depreotide WBS/SPECT (Tc-99m Dep.WBS). Initially, in all patients fluorine-18 2-fluoro-2- D-glucose-positron emission tomography-computed tomography ((18)F-FDG-PET-CT), Tc-99m Dep.WBS, and Tg measurements were performed. In the case of positive receptor scintigraphy, patients were treated with 20mg Sandostatin LAR (Novartis Pharmaceuticals, Basel, Switzerland) once per month intramuscularly over a period of 6 months followed by repeated (18)F-FDG-PET-CT, Tc-99m Dep.WBS, and Tg measurement to determine metabolic activity and tumor size. In case of tumor progression, the dose was increased to 30mg of Sandostatin LAR once per month., Results: Only 3 patients were able to undergo long-term treatment. Two patients were treated with octreotide long-acting release (LAR) for 1 year and 1 patient for 1(1/2) years. All patients showed progressive disease during the treatment: an increase of serum Tg on one hand and an increase in the number of lesions and extent in tumor size visible on FDG-PET-CT and Tc-99m Dep.WBS on the other. During the treatment there was no change in receptor expression, nevertheless, clear tumor progression under therapy with a somatostatin analogue was visible in FDG-PET-CT and in Tc-99m Dep.WBS., Conclusion: Our data demonstrate that all of our patients treated with a somatostatin analogue showed clinical progression and that our attempt to achieve a stabilization of the disease failed.

Background: Suppressive thyroid hormone therapy is generally a lifelong treatment for patients with differentiated thyroid cancer (DTC). However, long-standing thyrotropin (TSH) suppression is a risk factor for osteoporosis. Osteoprotegerin (OPG) and receptor activator of nuclear factor kappaB ligand (RANKL) are central regulators of bone turnover. The aim was to analyze the effects of a suppressive thyroid hormone therapy in males with DTC on the OPG/RANKL system and on bone metabolism., Patients and Methods: The OPG and soluble RANKL (sRANKL) were determined in 40 men (mean age, 53.2 years) with DTC on suppressive thyroid hormone therapy (TSH; 0.053 +/- 0.037 mU L(-1), duration 5.7 +/- 4.4 years) and 120 healthy controls matched for age. The markers of bone metabolism were C-terminal telopeptide of type I collagen in serum (sCTx) and osteocalcin (OC)., Results: The control group had OPG values (mean +/- SD) of 1.9 +/- 1.0 pmol L(-1) and sRANKL values of 0.40 +/- 0.62 pmol L(-1). In patients with DTC, results for OPG were 3.03 +/- 1.04 pmol L(-1) (P < 0.05) and for sRANKL were 0.13 +/- 0.16 pmol L(-1) (P < 0.05). The control group presented values for sCTx of 2669 +/- 1132 pmol L(-1) and for OC of 17.89 +/- 6.5 ng mL(-1). Patients with DTC on suppressive thyroid hormone therapy had increased sCTx values of 3810 +/- 2020 pmol L(-1) (P = 0.03) but comparable OC values of 19.21 +/- 7.67 ng mL(-1) (NS)., Conclusions: Suppressive thyroid hormone therapy in men with DTC increased bone degradation and induced significant changes in the OPG/RANKL system. These changes include, besides the risk of osteoporosis, possible negative effects on the vascular function and an increased risk of cardiovascular disease.

Inflammatory bowel disease (IBD) requires a complex diagnostic workup. In contrast to endoscopy and cross-sectional imaging methods, scintigraphy enables a complete survey of the whole small and large bowel intestinal tract with a single noninvasive examination. For detection of IBD, 80% to 90% sensitivity and 92% to 100% specificity can be found for conventional scintigraphy. A new imaging method like fluorine-18 (F-18) fluorodeoxyglucose PET has been shown to be useful in tumor diagnostics. A major problem in PET is the limited anatomic information and nonspecific tracer uptake within the colon, however, which may lead to false-positive results. New imaging methods like combined PET/CT can help to solve the problem, because physiologic tracer uptake can be easily distinguished from pathologic lesions as a result of the anatomic detail provided by CT.

The cardiocirculatory changes in hyperthyroidism seem to be an accommodation to the increased metabolic demands and lead to an increased perfusion of the peripheral tissues. Due to the influence of elevated thyroid hormone levels, contractility, stroke volume, resting heart rate, and contraction and relaxation velocity of the left ventricle increase. Caused by direct effect on the smooth vascular muscle, systemic vascular resistance is decreased with the consequence of a diminished afterload and an increased cardiac efficiency. The activation of the renin-angiotensin-aldosteron system and the increased production of erythropoietin additionally lead to an increased blood volume, which increases cardiac preload together with the increased venous backflow. Manifest hypothyroidism is characterized by bradycardia and diastolic dysfunction in rest and systolic dysfunction at stress. Despite a slight increase of diastolic blood pressure due to an increased systemic vascular resistance, blood pressure remains nearly stable because of diminished cardiac output. Hypercholesterinaemia and diastolic hypertension in hypothyroid patients can lead to the development of arteriosclerosis and coronary heart disease (CHD). Also subclinical hypothyroidism is associated with a significantly higher risk for arteriosclerosis and CHD, whereas subclinical hyperthyroidism seems to be associated with an increased mortality for all reasons, especially for cardiovascular diseases.

Introduction: The aim of the study was to investigate the current thyroid carcinoma (TC) incidence in Carinthia, a former iodine-deficient, goiter-endemic region in Austria with approximately 550,000 inhabitants from 1984 to 2001. Using age-cohort analysis we analyzed the TC incidence under the impact of two regional risk factors: the contamination of Austrian soils by the radioactive fallout in from Chernobyl 1986 and the increased iodination of table salt in a general program of goiter prophylaxis begun in 1991. To evaluate the characteristics of TC incidence, we compared the results of the periods 1984-1989, 1990-1995, and 1996-2001., Results: A total of 734 TC cases were diagnosed. Papillary, follicular, medullary, oxyphilic, and anaplastic TC accounted for 76%, 18%, 3%, 1%, and 2%, respectively. The female to male ratio was 3:1. The annual incidence rate increased by 8.05% in females and 11.6% in males. TC cases younger than 40 years of age accounted for 22.6%, with a rate increase of 18% per year in young males, the female-to-male ratio decreased from 8.3, 6.1, 2.7 younger than 40 in the compared periods. Along with a further increase in papillary TC incidence and papillary thyroid carcinoma (PTC) follicular thyroid carcinoma (FTC) ratio in the adult population, the ratio tended to decrease in the younger than 40-year-old population. T4 class TC and loco-regional lymph node involvement increased significantly., Interpretation: The observed changes in TC incidence, particularly in the young population, as in adults, could be linked to the abovementioned risk factors involved in the initiation and early growth of TC, and iodine may play a role in stimulating overall thyroid activity.

Aim: To evaluate the role of F-18-fluorodeoxyglucose positron-emission tomography (F-18 FDG PET) in the follow-up of breast carcinoma in case of clinical suspicion of local recurrence or distant metastases and/or tumor marker increase in correlation to conventional imaging., Material and Methods: Retrospective analysis of the results of F-18 FDG PET (ECAT ART(R), Siemens CTI MS) of 62 patients (age 58.5 +/- 12.8) with surgically resected breast carcinoma (time interval after surgery, 86 +/- 82 months, mean follow-up 24 +/- 12.6 months). Patient- and lesion-based comparison with conventional imaging (CI) including mammography (MG), ultrasonography (US), computerized tomography (CT), magnetic resonance imaging (MRI), radiography (XR) and bone scintigraphy (BS). Furthermore, we evaluated the influence on tumor stage and therapeutic strategy. A visual qualitative evaluation of lesions was performed., Results: On a patient base, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for detecting local recurrence or distant metastases were calculated to be 97%, 82%, 87%, 96% and 90% compared with 84%, 60%, 73%, 75% and 74% with CI. On a lesion base, significantly more lymph node (84 vs. 23, P < 0.05) and fewer bone metastases (61 vs. 97, P < 0.05) could be detected by using F-18 FDG PET compared with CI. Sclerotic bone lesions were predominantly detected by BS. On the other hand, there were several patients with more FDG positive bone lesions and also mixed FDG positive/Tc-99m methylenediphosphonate (MDP) negative and FDG negative/Tc-99m MDP positive metastases. In case of normal tumor markers, sensitivity, specificity, PPV, NPV and accuracy for detecting local recurrence or distant metastases were calculated to be 100%, 85.0%, 78.6%, 100% and 90.3% for FDG PET and 80%, 50%, 50%, 80% and 61.5% for CI. An upstaging could be observed in 9.7% (6/62) and downstaging in 12.9% (8/62), leading to a change in therapeutic regimen in 13 patients (21%)., Conclusions: F-18 FDG PET demonstrates apparent advantages in the diagnosis of metastases in patients with breast carcinoma, compared with conventional imaging on a patient base. On a lesion base, significantly more lymph node and less bone metastases can be detected by using F-18 FDG PET compared with conventional imaging, including bone scintigraphy. In patients with clinical suspicion but negative tumor marker profile, too, F-18 FDG PET seems to be a reliable imaging tool for detection of tumor recurrence or metastases. Considering the high predictive value of F-18 FDG PET, tumor stage and therapeutic strategy will be reconsidered in several patients.

Aim: Patients with differentiated thyroid carcinoma (DTC) must receive suppressive levothyroxine (LT(4)) therapy for the rest of their lives. The literature, however, presents conflicting results on how this affects bone metabolism. The aim of this study was to assess the influence of the estrogen status and LT(4) therapy, in particular LT(4) dosage in micrograms per kilograms (microg/kg), on bone metabolism in female patients with DTC., Material and Methods: Three markers of bone metabolism (C-terminal telopeptide of type I collagen in serum [SCTx]; N-terminal telopeptide of type I collagen in urine [U-NTx]; and osteocalcin [OC]) were investigated in four groups: group REF (healthy premenopausal female controls), group DTC-ES (premenopausal women with DTC and normal estrogen levels), group DTC-ED (postmenopausal women with DTC and estrogen deficiency), and group DTC-HRT (postmenopausal women with DTC undergoing hormone replacement therapy [HRT]). All patients with DTC were on a well-adjusted suppressive LT(4) therapy with TSH levels 0.1 mU/L or less., Results: In group DTC-ES bone turnover was comparable to group REF, whereas in group DTC-ED, all three markers were significantly increased as compared to groups REF and DTC-ES. In group DTC-HRT, the HRT normalized U-NTx and OC. However, in this group S-CTx was not completely normalized by HRT in all patients, although also significantly lowered compared to group DTC-ED. The analysis of LT(4 )dosage per kilogram showed that premenopausal DTC-patients had increased markers of bone metabolism if LT(4) dosage exceeded 2.6 microg/kg. Estrogen-deficient patients with DTC, however, had a much lower critical LT(4) dosage, above which increased markers of bone metabolism were seen., Conclusion: A well-adjusted suppressive LT(4) therapy of less than 2.6 microg/kg and normal estrogen levels do not seem to increase bone metabolism in estrogen-sufficient patients with DTC. The normalization of an estrogen deficiency by HRT or other antiresorptive therapies and minimal suppressive dosages of LT(4) are attempts to optimize the care of patients with DTC. In postmenopausal patients with DTC and patients with DTC who require LT(4) dosages in excess of 2.6 microg/kg, the information provided by markers of bone metabolism may help to prevent bone damage.

Background: The aim of this study was to evaluate the usefulness of fluorine-18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in the preoperative assessment of suspicious thyroid nodules., Methods: A total of 43 patients were examined before surgical resection. In all patients, imaging was obtained at 70 minutes after the intravenous administration of 180 MBq (18)F-FDG. Standard uptake values (SUVs) were calculated., Results: A total of 16 patients with thyroid carcinomas (11 papillary, 3 follicular, 2 anaplastic), 23 thyroid adenomas (11 microfollicular, 10 Hurthle cell, 2 macrofollicular), and 4 patients with degenerative goiter were found. (18)F-FDG uptake in Hurthle cell adenoma, thyroid cancer, microfollicular adenoma, degenerative goiter, and macrofollicular adenoma was 4.4 +/- 2.2, 3.7 +/- 1.9, 1.6 +/- 0.3, 1.2 +/- 0.2, and 0.9 +/- 0.1, respectively. Significant differences were observed between thyroid carcinomas and both microfollicular adenomas and degenerative goiters (P < 0.05), and between Hurthle cell adenomas and both microfollicular adenomas as well as degenerative goiter (P < 0.05). For diagnosis of thyroid carcinoma, 100% sensitivity, 63% specificity, and 100% negative predictive value was found when a cutoff value for SUV of 2 was used., Conclusions: Our results indicate that thyroid carcinomas, in contrast to most benign thyroid nodules, demonstrate significantly increased glucose metabolism. (18)F-FDG PET is unlikely to differentiate successfully all benign tumors from malignant tumors, but it can help select patients who need surgery, especially if cytology is inconclusive or malignancy cannot be excluded.

The aim of our study was a direct comparison of the ability of positron-emission tomography with FDG-PET and of magnetic resonance imaging (MRI) to determine whether breast lesions were benign or malignant and of the two imaging methods capability of depicting eventual multifocal disease. We performed both PET and MRI in 36 patients (40 lesions) who were scheduled for surgery because of suggestive mammographic, sonographic and/or clinical findings. A final histological classification was available for all lesions. Tumour size ranged from 5 to 45 mm (mean 16.7 mm). Sensitivity for lesions, sensitivity for patients, specificity for lesions and specificity for patients were 68.0%, 76.2%, 73.3%, and 73.3% for PET and 92.0%, 95.2%, 73.3%, and 73.3% for MRI, respectively. MRI was more sensitive than FDG-PET in disclosing malignant breast tumours and was also more accurate than FDG-PET in the assessment of multifocal disease. The lower sensitivity of FDG-PET than of MRI seems to be due to difficulties in reliable imaging of carcinomas smaller than 10 mm and of lobular carcinomas.

Background: The aim of this retrospective study was to evaluate the accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) images, which were interpreted under daily routine conditions, in patients with Hodgkin's disease (HD) or non-Hodgkin lymphoma (NHL) for restaging after chemotherapy and/or radiotherapy. For this purpose, 18F-FDG-PET results were compared with morphological imaging methods and the patients' clinical background., Methods: 121 PET images of 93 lymphoma patients (44 HD, 49 NHL) were investigated after chemotherapy/radiotherapy. For PET imaging, 160-200 MBq 18F-FDG was administered intravenously, followed by an infusion of 20 mg Furosemid in 250 mL saline. Whole-body 18F-FDG-PET images were obtained using a partial-ring PET scanner without attenuation correction. The morphological imaging consisted in computed tomography and ultrasound (CT/US) in all patients, additional MRI in some patients, and iliac crest biopsy in cases of suspicious bone marrow involvement. The standard of reference was composed of biopsy data, clinical status at the time of investigation, and follow-up of at least 12 months. The PET images were evaluated for their sensitivity, specificity and accuracy based on written reports, which were compiled from other imaging data and the clinical history of the patients., Results: Sensitivity, specificity, and accuracy of 18F-FDG-PET was 91 %, 81 %, and 85 %; of CT/US, 88 %, 35 %, 56 %, respectively. Major sources of error in 18F-FDG-PET were due to asymmetric muscular hypermetabolism and inflammatory lesions misinterpreted as persistent viable lymphoma tissue. Furthermore, secondary malignancies other than lymphomas were another reason for misinterpretations of 18F-FDG-PET studies., Conclusions: 18F-FDG-PET showed a comparable sensitivity but a higher specificity and accuracy compared with CT/US. To achieve a high accuracy in 18F-FDG-PET, the nuclear medicine specialist needs imaging and clinical data as background information, which can only be acquired through close co-operation with the referring clinicians. Pharmacological muscular relaxation in the course of 18F-FDG-PET imaging may be advisable, as nonspecific muscular hypermetabolism was one of the problems at the image readings and a source of incorrect 18F-FDG-PET interpretations.

We report on the case of a 86-year-old male patient with a rapidly growing nodule within the right lobe of the thyroid gland, which after hemithyroidectomy, turned out to be a mucosa-associated lymphoid tissue (MALT) lymphoma of the thyroid gland. In addition, Hashimoto's thyroiditis was reported in the thyroid tissue adjacent to the MALT lymphoma. During follow-up a second nodule emerged within the left lobe and, because of evidence of MALT lymphoma recurrence, F-18-FDG-PET was performed. F-18-FDG-PET imaged a clearly increased accumulation within the whole left lobe and isthmus. Thus, no differences in the degree of hypermetabolism could be imaged between the nodule and the adjacent thyroid tissue. To our knowledge, this is the first report about F-18-FDG-PET in a patient with MALT lymphoma of the thyroid. Literature search revealed only a few cases of MALT lymphomas in locations other than the thyroid gland that were studied with F-18-FDG-PET. In no case was F-18 FDG accumulation seen in the MALT lesions. However, clear F-18 FDG accumulation was reported in some patients with Hashimoto's thyroiditis. It is concluded that the intensive F-18-FDG accumulation within the whole left lobe and isthmus of the presented case was due to the coexisting Hashimoto's thyroiditis. Consequently, F-18-FDG-PET imaging does not seem to be indicated in a patient with MALT lymphoma and known Hashimoto's thyroiditis in order to evaluate the status of the MALT lymphoma.

Differentiated thyroid cancer is a rare tumour with an incidence of 4 - 9/100,000/year. For preoperative assessment of thyroid nodules, ultrasonography (US) and US-guided fine needle aspiration biopsy are the methods of choice to detect thyroid cancer. The value of preoperative fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) in differentiating malignant from benign nodules, especially in cases of follicular proliferation, has not yet been evaluated. After thyroidectomy and radioiodine remnant ablation, several methods are used to follow patients with differentiated thyroid cancer, including serum thyroglobulin, ultrasonography of the neck, iodine-131 (131I) whole body scintigraphy (WBS) and scintigraphy with nonspecific tracers such as technetium-99 m ((99m)Tc) Tetrofosmin or Sestamibi. Whereas the specificity of 131I-WBS is high, sensitivity is low, especially if one takes into account that only two-thirds of recurrences or metastases store iodine. With the introduction of 18F-FDG in oncology, it is also used for the detection of local recurrences and metastases of differentiated thyroid cancer. Elevated thyroglobulin but negative 131I-WBS belongs to the 1a indications for 18F-FDG-PET in oncology according to the German Consensus Conference 2000. The sensitivity for detecting 131I-negative metastases with 18F-FDG-PET can be increased by elevated thyroid-stimulating hormone (TSH) after withdrawal of thyroid hormone therapy or after intramuscular injection of recombinant TSH. Most of the 131I-negative metastases demonstrate 18F-FDG uptake, which represents rapid tumour growth and poor differentiation, whereas most of the 131I-positive metastases are 18F-FDG negative. The combination of 131I-WBS and 18F-FDG-PET leads to an increase in the detection rate to more than 90 - 95 % in cases of elevated thyroglobulin, because well- and less-differentiated cancer cells may be present in one patient. In rare cases, a recurrent tumour or metastasis may accumulate 131I as well as 18F-FDG. In these patients, it may be possible that well- and less-differentiated cells are present in one metastasis. The early use of 18F-FDG-PET in patients with elevated thyroglobulin, especially in the case of negative 131I-WBS, changes the therapeutic strategy in up to half of the patients (surgery, external radiation).

The case of an eight years old African boy who suffers from sickle cell-thalassemia is presented. In the course of the disease frequent pain attacks occurred within the abdomen and extremities, recently also within the trunk. Local pain, at some occasions in combination with local swelling and always positive laboratory parameters for inflammation, hindered a solely clinical differentiation between bone infarcts and osteomyelitis. Bone scintigraphy, eventually in combination with bone marrow scintigraphy, can assist the clinician in the differentiation of aseptic bone infarcts versus secondary osteomyelitis. Based on the presented case scintigraphic results for bone infarcts, osteomyelitis and special scintigraphic pattern seen in sickle cell disease are presented. Furthermore, problems regarding the interpretation of the scintigraphies in relation to the delayed time after the beginning of pain attacks are discussed.

Until 1963 Austria was an extremely iodine-deficient area with low iodine intake and high goiter prevalence. Therefore, for the first time in 1963, salt iodination with 10 mg of potassium iodide per kilogram of salt was introduced by federal law. Twenty years after this salt iodination, however, investigations in schoolchildren demonstrated iodine deficiency grade I to II according to the World Health Organization (WHO) (urinary iodine excretion, 42-75 microg/g Crea) and goiter prevalence of far more than 10%. In 1990, salt iodination was increased to 20 mg of potassium iodide per kilogram of salt. In 1994, further investigations in schoolchildren demonstrated an increase of urinary iodine excretion (121 microg/g Crea) and a reduction of goiter prevalence below 5%, with the exception of pupils ages 14-19 (12%). In the year 2000, 10 years after the increase of salt iodination in Austria, 430 nonselected adult inhabitants of three communities in Carinthia (a county of Austria) were investigated for iodine excretion, goiter prevalence, and prevalence of thyroid autoantibodies. This study demonstrated that although iodine supply is sufficient now in Austria (males, 163.7 microg of Crea; females, 183.3 microg of iodine per gram of Crea), goiter prevalence is still high in the elderly, who lived for a longer period of iodine deficiency (34.3% in women and 21.3% in men), whereas goiter prevalence in younger people up to age 40 years is below 5%. It could also be shown that the percentage of thyroid autoantibodies is now as high as in other countries with sufficient iodine supply (3.19% in males, 5.17% in females). In addition to the changes of urinary iodine excretion and goiter prevalence because of salt iodination, changes of incidence in hyperthyroidism and histologic types of thyroid cancer are discussed in this paper. In conclusion, the introduction of salt iodination led to an improvement in iodine supply with a marked reduction of goiter prevalence in people who were born after 1963, but also to an increase in hyperthyroidism and autoimmune thyroid diseases as well as changes in histologic types of thyroid cancer.

Collagenous and eosinophilic colitis are rare diseases characterised by chronic watery diarrhoea. Radiographic evaluation of the gastrointestinal tract and colonoscopy are usually non-diagnostic since as many as one-third of patients will have minor abnormalities. To date a few investigators have reported increased fluorine-18 fluorodeoxyglucose ((18)F-FDG) uptake on positron emission tomography (PET) in patients with acute enterocolitis, but there have been no reports on the use of (18)F-FDG PET for the diagnosis of collagenous or eosinophilic colitis in an early clinical stage. The aim of this preliminary study was to evaluate the usefulness of (18)F-FDG PET in the early diagnosis of patients with colitis. We investigated five women (mean age 61.2+/-12.1 years) who had been diagnosed as having colitis in an early clinical stage. In all but one of the patients, the diagnosis of colitis was based on biopsy. Magnetic resonance colonography, ultrasonography and colonoscopy were performed in all but one of the patients. Two women were identified as having collagenous colitis in an early clinical stage. Another two patients had eosinophilic colitis. The morphological imaging methods, magnetic resonance colonography and ultrasonography, yielded no suspicious findings, and the results of colonoscopy similarly showed no abnormalities. One patient had colitis due to bacterial infection. In all patients (18)F-FDG PET showed a pathological increase in tracer uptake in the large bowel, suggestive of colitis. In four of the five patients, colitis was confirmed by histology, and in one, by bacterial analysis. (18)F-FDG PET was able to detect colitis in an early clinical stage, when morphological imaging methods and colonoscopy were non-diagnostic. The early performance of (18)F-FDG PET imaging in patients with possible colitis is encouraging.

The objective of this epidemiologic study was to determine the volume of the thyroid gland as well as urinary iodine excretion in dependence on age and gender in a population from an area of low natural iodine supply now receiving iodine prophylaxis. In 430 persons from three communities in the province of Carinthia, Austria, we determined thyroid volume via sonography as well as urinary iodide excretion. As in numerous other European countries, natural iodine supply is insufficient in Austria. Therefore, to reduce goiter incidence, iodization of common salt with 10 mg potassium iodide (KI) per kilogram of NaCl was made mandatory in Austria in 1963 by federal law. In 1990, the amount of iodine addition was increased to 20 mg KI per kilogram of NaCl. Our results show that mean urinary iodide excretion in the persons investigated was altogether satisfactory (males: 163.7 microg of iodine per gram of creatinine; females: 183.3 microg of iodine per gram of creatinine). Goiter prevalence was 34.3% in women and 21.3% in men. An increase in goiter occurrence with age was noted in both genders. The increase in goiter prevalence was particularly obvious in the age group older than 40, i.e., among those participants who had spent at least a certain span of their lives in an area of iodine deficiency. Thus, the most likely reason for the persistently high goiter prevalence is not current iodine deficit but rather the high number of goiters that had developed previously at the time of iodine deficiency and were unable to undergo regression in spite of today's comparatively good iodine supply situation.

A variety of indications for radiosynoviorthesis have been reported in literature, but the clinical outcome differs and depends on the primary disease and the pre-existing degenerative changes. This metaanalysis was carried out to establish groups for radiosynoviorthesis based on clinical outcome with respect to primary disease, clinical stage and the pre-existing degenerative changes. The literature search was carried out using the MEDLINE search term 'radionuclide synovectomy'. Based on reports in the literature we determined groups for radiosynoviorthesis for clinical use. Our literature list comprised 2190 joints that were treated with radiosynoviorthesis. The overall response rate for all treated joints was 72.5+/-17%. The mean improvement rate for the treated joints in rheumatoid arthritis was 66.7+/-15.4%. For osteoarthritis the success rate was 56+/-11%, with better results in case of minimal radiological changes. Radiosynoviorthesis in patients with changes according to Steinbrocker I and II was successful in 72.8+/-12.3%, and in 64+/-17.3%, respectively. Steinbrocker III and IV had a mean success rate of 52.4+/-23.6%. In the case of haemophilia and Willebrand's disease a reduction of joint bleedings and factor usages after radiosynoviorthesis was evident in 91+/-4.3%. In patients with pigmented villonodular synovitis radiosynoviorthesis was successful in 77.3+/-25.3%. It is concluded that radiosynoviorthesis provides better results in rheumatoid arthritis than in osteoarthritis. Minimal or moderate changes according to Steinbrocker stages I and II respond better to radionuclide therapy than do stages III and IV. Deformed or unstable joints might fail treatment and therefore surgical interventions should be considered. Close cooperation with orthopaedists and rheumatologists is necessary to consider radiosynoviorthesis in each patient to ensure optimal medical care.

Aim: Retrospective evaluation of Tc-99m ciprofloxacin (infection) scintigraphy consecutively performed in a series of patients clinically suspected for peripheral osteomyelitis (OM), spondylodiscitis (SD) and fever of unknown origin (FUO)., Methods: A total of 20 patients clinically suspected for OM (n = 12), SD (n = 3) and FUO (n = 5) were included in our retrospective analysis. The additional criterion was a positive 3-phase bone scan for OM, or a 2-phase bone scan in case of SD. Planar whole body scans and static acquisitions were performed 1 and 4 h after application of 370 MBq Tc-99m ciprofloxacin. In 10 patients with suspected OM, additional immunoscintigraphy using Tc-99m labelled monoclonal antibodies (Mab BW 250/183) was performed and the correlation of infection to bloodpool and antigranulocyte scintigraphy was analysed., Results: OM: Bacterial infection was confirmed in 8 of 15 lesions. Infection demonstrated true positive (TP) results in 7 of 8, true negative (TN) results in 2 of 7, false positive (FP) results in 5 of 7 patients and one false negative (FN) result. A strong correlation could be demonstrated between T/NT ratios of infection and bloodpool Tc-99m medronate imaging (r = 0.84, 0.88) and between infection and BW 250/183 (r = 0.92, 0.90). Using a threshold of 2.0 for T/NT ratio, only TP results could be observed whereas a T/NT in the range of 1.0-2.0 could not discriminate between septic and aseptic inflammation. Concordant results with Mab BW 250/183 could only be observed in 5 of 10 patients (4 TP, 1 TN) by showing 4 FP and 1 FN lesions with IF., Conclusion: Non-specific uptake of infection can be observed in a variety of clinical situations with moderate uptake, by showing a strong correlation with blood-pool imaging. Nevertheless, intense uptake may be specific for septic inflammation.

Aim: The goal of this study was to assess the accuracy and limitations of ultrasound guided fine-needle aspiration biopsy (ug-FNAB) of solitary thyroid nodules., Methods: The ug-FNAB results of 538 patients with solitary thyroid nodules, who afterwards underwent thyroid surgery, were compared retrospectively with the histology. Patients with multinodular goiter were excluded from the study. Ug-FNAB was performed on growing and/or hypoechoic and/or hypofunctional nodules. The ug-FNAB results were grouped as follows: group 1: malignant (n = 44); group 2: malignancy cannot be ruled out (n = 173); group 3: non-malignant (n = 296), group 4: inadequate (n = 25)., Results: When the cytological results of group 1 and group 2 were interpreted as being malignant and those of group 3 as being benign, sensitivity, specificity and accuracy of ug-FNAB were 96.7%, 65.8% and 69.5% respectively. The 62 thyroid carcinomas (TC) biopsied presented in 59 cases a suspicious or malignant cytology (95.2%). The smallest TC diagnosed by ug-FNAB had a diameter of 0.5 cm and 36.4% of all papillary TC < or = 1 cm displayed stage pT4. The histology verified a TC in 18 cases out of the 173 ug-FNABs in group 2. Non-malignant ug-FNABs were confirmed by histology in 294 patients (99.3%) in group 3. In 4.65% of the ug-FNABs inadequate material was aspirated., Conclusion: Nodules with non-suspicious ug-FNAB results can be safely followed-up by sonography, as the cytological diagnoses were verified in more than 99% by histology. Papillary TC can be diagnosed with ug-FNAB very accurately. As stage pT4 was present in more than one third of patients with papillary TC < or = 1 cm, ug-FNAB is also recommended for thyroid nodules 0.5-1 cm in diameter located adjacent to the thyroid capsule. However, microfollicular proliferations remain the limitation of ug-FNAB, as the cytology cannot distinguish between benign adenoma and follicular TC.

The aim of this study was to evaluate the usefulness of 18F-FDG PET in the diagnosis and staging of primary and recurrent malignant head and neck tumours in comparison with conventional imaging methods [including ultrasonography, radiography, computed tomography (CT) and magnetic resonance imaging (MRI)], physical examination, panendoscopy and biopsies in clinical routine. A total of 54 patients (13 female, 41 male, age 61.3+/-12 years) were investigated retrospectively. Three groups were formed. In group I, 18F-FDG PET was performed in 15 patients to detect unknown primary cancers. In group II, 24 studies were obtained for preoperative staging of proven head and neck cancer. In group III, 18F-FDG PET was used in 15 patients to monitor tumour recurrence after radiotherapy and/or chemotherapy. In all patients, imaging was obtained at 70 min after the intravenous administration of 180 MBq 18F-FDG. In 11 of the 15 patients in group I, the primary cancer could be found with 18F-FDG, yielding a detection rate of 73.3%. In 4 of the 15 patients, CT findings were also suggestive of the primary cancer but were nonetheless equivocal. In these patients, 18F-FDG showed increased 18F-FDG uptake by the primary tumour, which was confirmed by histology. One patient had recurrence of breast carcinoma that could not be detected with 18F-FDG PET, but was detected by CT. In three cases, the primary cancer could not be found with any imaging method. Among the 24 patients in group II investigated for staging purposes, 18F-FDG PET detected a total of 13 local and three distant lymph node metastases, whereas the conventional imaging methods detected only nine local and one distant lymph node metastases. The results of 18F-FDG PET led to an upstaging in 5/24 (20.8%) patients. The conventional imaging methods were false positive in 5/24 (20.8%). There was one false positive result using 18F-FDG PET. Among the 15 patients of group III with suspected recurrence after radiotherapy and/or chemotherapy, 18F-FDG was true positive in 7/15 (46.6%) and true negative in 4/15 (26.6%). The conventional imaging methods were true positive in 5/15 (33.3%) and true negative in 4/15 (26.6%). One false negative (6.6%) and three false positive findings (20%) on 18F-FDG PET were due to inflamed tissue. The conventional imaging methods were false positive in three (20%) and false negative in three cases (20%). It is concluded that in comparison to conventional diagnostic methods, 18F-FDG PET provides additional and clinically relevant information in the detection of primary and metastatic carcinomas as well as in the early detection of recurrent or persistent head and neck cancer after radiotherapy and/or chemotherapy. 18F-FDG PET should therefore be performed early in clinical routine, usually before CT or MRI.

The aim of this study was to examine different influences on bone degradation (estrogen status, thyroid function, parathyroid function, bone metastases) with special interest focusing on the significance of suppressive levothyroxine therapy (LT4) on bone degradation in patients with differentiated thyroid carcinoma (DTC). Two markers of bone degradation (ELItest NTx = U-NTx; Serum CrossLaps = S-CTx) were used (1) to quantify the influence of different metabolic influences on bone degradation and (2) to compare these two markers with each other. One hundred forty samples of 98 female patients ages 23-86 years were analyzed. The correlation between the two assays of bone degradation was high (r = 0.825; p < 0.001). Both assays demonstrated that estrogen deficiency, hyperparathyroidism, and bone metastases caused significant increases of bone degradation. A suppressive LT4 therapy, as used for patients with DTC, led to no significant increases of S-CTx and U-NTx. The study indicates that a well-controlled suppressive LT4 therapy has only a minor effect on the degree of bone degradation and that a possible estrogen deficiency in patients with DTC has a greater impact on bone degradation. Thus, female patients with DTC on suppressive LT4 therapy and estrogen deficiency may benefit from hormone replacement therapy, as patients with DTC and normal estrogen levels presented similar results to euthyroid controls.

A 46 years old man, who showed a painful and progressive deformity of the left radius, is presented. After some months a fracture within the affected bone area occurred. The diagnostic procedures including X-ray, MRI, scintigraphy and histology were controversial. Both fibrous dysplasia and Paget's disease of bone were suspected. The critical analysis of all results concluded that the most likely diagnosis was fibrous dysplasia. Unaware of the diagnostic discrepancies, the patient received a therapy with pamidronate 3 x 60 mg intravenously, which improved symptoms. After 14 months, the patient complained again about pain in the left radius. After a second therapy with pamidronate the patient currently exhibits no symptoms. The controversial diagnostic results and the applied therapeutic procedure are discussed.

In iodine-sufficient areas any thyroid nodule has to be regarded as potentially malignant, whereas in iodine-deficient areas (endemic goiter areas) thyroid nodules, even multinodular goiter, are frequent. The majority of thyroid nodules in an endemic goiter area can be regarded as being most likely benign and thus not all patients with multinodular goiter have to undergo surgery. The major diagnostic aim and challenge is the selection for surgery of only those patients who suffer from mechanical obstruction due to large goiter and those who present with nodules suspicious of malignancy. Thus, for these cases the question of accurately excluding or verifying malignancy is essential for the patient and the specialist of nuclear medicine or endocrinology. A variety of investigations may be used for the preoperative evaluation of thyroid nodules, although currently sonography and fine-needle biopsy have to be regarded as the key investigations to clarify preoperatively the dignity of thyroid nodules. The article presents the indications and limitations of the different methods in use for the evaluation of thyroid malignancy. The authors present a diagnostic algorithm for the preoperative evaluation of thyroid malignancy with special respect to problems occurring in a(n) (former) endemic goiter area.