E Kresnik

Klinikum-Klagenfurt am Wörthersee, Celovec, Carinthia, Austria

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Publications (76)166.34 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Today's available therapeutic options in head and neck cancer patients have led to better treatment modalities tailored to the individually clinical staging of the patients towards a risk adapted tumour management. This, however, is only possible with an accurately pretherapeutic diagnostic regimen and closely posttherapeutic follow-up. These issues were discussed by nuclear medicine experts, otorhinolaryngologists, oral surgeons, radiologists, radio-oncologists and oncologists in a meeting that took place in Pörtschach, Austria, on 05 May 2006. The aim was to discuss the impact and indications of performing FDG PET/CT in patients with head and neck cancer and to outline possible future perspectives. FDG PET/CT is recommended for a better pretherapeutic staging in stage IV according to UICC and should be the method of choice in CUP with lymph node metastases. FDG PET/CT should be performed 3 - 4 months after radiation-/radiochemotherapy to diagnose viable tumour and to avoid false positive results. To evaluate the position and effectiveness of FDG PET/CT in therapy-monitoring further studies are needed. In case of radiation therapy FDG PET/CT allows a tailored treatment of patients with an accurate design of the target volume to reduce damage to the surrounding tissues. The interdisciplinary consensus reached by the experts is not intended to recommend standard guidelines in the management of head and neck cancer but to summarise and stress the impact of FDG PET/CT on the basis of the present literature and current clinical practise.
    Laryngo-Rhino-Otologie 03/2009; 88(2):84-90. · 0.82 Impact Factor
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    ABSTRACT: 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. 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. 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. 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.
    European journal of nuclear medicine and molecular imaging 06/2008; 35(5):976-83. · 5.11 Impact Factor
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    ABSTRACT: 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.
    Nuklearmedizin 02/2008; 47(6):239-47. · 1.67 Impact Factor
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    ABSTRACT: 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. 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). 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). 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.
    Thyroid 02/2008; 18(1):27-33. · 3.54 Impact Factor
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    ABSTRACT: 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. 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. 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. 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.
    European journal of nuclear medicine and molecular imaging 05/2007; 34(4):487-95. · 5.11 Impact Factor
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    ABSTRACT: 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. 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. 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). 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.
    Nuklearmedizin 01/2007; 46(6):252-6. · 1.67 Impact Factor
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    ABSTRACT: Head and neck cancers are rising in incidence. In the diagnosis of malignant head and neck cancer, conventional morphological imaging methods, i.e. ultrasonography, radiography, computerised tomography (CT) and magnetic resonance imaging (MR) play a routine role besides clinical investigation. Despite these diverse techniques, the primary tumour often cannot be found. Furthermore, for staging purposes as well as for the detection of tumour recurrence after chemotherapy and/or radiotherapy, morphological examination techniques such as CT and MR are of limited accuracy. Due to promising results in the literature, 18F-fluorodeoxyglucose-positron emission tomography has been playing an increasing role in the assessment of malignant head and neck cancer. The authors present a literature review as well as their own data in comparison to conventional imaging methods.
    Imaging Decisions MRI 01/2007; 11(2):24-32.
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    ABSTRACT: 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. 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. 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. 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.
    Thyroid 12/2006; 16(11):1113-9. · 3.54 Impact Factor
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    ABSTRACT: 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. 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). 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). 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.
    European Journal of Clinical Investigation 09/2006; 36(8):566-73. · 3.37 Impact Factor
  • PET Clinics 01/2006; 1(2):153-162.
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    ABSTRACT: 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. 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. 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.
    Thyroid 05/2004; 14(4):277-86. · 3.54 Impact Factor
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    ABSTRACT: 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. 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. 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%). 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.
    Investigative Radiology 06/2003; 38(5):250-6. · 5.46 Impact Factor
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    ABSTRACT: 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. 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. 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. 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.
    Thyroid 05/2003; 13(4):347-56. · 3.54 Impact Factor
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    ABSTRACT: 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. 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. 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. 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.
    Surgery 03/2003; 133(3):294-9. · 3.37 Impact Factor
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    ABSTRACT: 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.
    The Breast 03/2003; 12(1):17-22. · 2.49 Impact Factor
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    ABSTRACT: 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. 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. 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. 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.
    Acta Medica Austriaca 02/2003; 30(2):41-7.
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    ABSTRACT: 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.
    Wiener Medizinische Wochenschrift 02/2003; 153(3-4):89-92.
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    ABSTRACT: 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).
    Acta Medica Austriaca 02/2003; 30(1):17-21.
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    01/2003;
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    ABSTRACT: 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.
    Thyroid 11/2002; 12(10):903-7. · 3.54 Impact Factor