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Biomedical subjects

F Grünwald

Publications and source records attributed to F Grünwald.

At least 73 records · Page 4Linked to original sources
PubMed1999

Non-131I-scintigraphy in the treatment and follow-up of thyroid cancer. Single-photon-emitters or FDG-PET?

With respect to further therapeutic options, whole-body 131I scintigraphy (WBS) is the most important functional imaging technique during treatment and follow-up of differentiated thyroid cancer. But in many patients, thyroid cancer tissue does not concentrate 131I and can therefore not be localized using WBS. In addition to morphologic techniques, which have a low specificity in many cases, other methods are necessary to localize tumor tissue in these patients. Besides 201Tl, which has been used initially as a tumor-seeking agent, sestamibi, tetrofosmin and 18F-DG for PET imaging have been evaluated in differentiated thyroid carcinoma. This paper summarizes the clinical impact of functional imaging with tracers besides 131I. In direct comparison, 18F-DG-PET has the highest sensitivity, which exceeds 80% in cases with negative WBS. If available, this method should be considered in all patients suffering from differentiated thyroid cancer with suspected recurrence and/or metastases, particularly in cases with elevated thyroglobulin values and negative WBS. But also 99mTc-labeled tracers can be used to detect tumor tissue with a sufficient sensitivity. In medullary thyroid cancer, which presents frequently with diagnostic difficulties, 111In-octreotide, 99mTc-(V)-DMSA, 131I/123I-mIBG, and anti-CEA can be used, in addition.

Fluorodeoxyglucose F18↗
PubMed1999

[Role of positron emission tomography (PET) and single photon emission tomography (SPECT) in so-called "multiple chemical sensitivity"].

Functional imaging with SPECT and PET is increasingly used to prove evidence for the existence of a syndrome "Multiple Chemical Sensitivity" (MCS) and plays a major role in legal trials to justify compensation for the exposure to solvents. This paper critically reviews the literature on the use of SPECT and PET for the determination of MCS. The authors come to the conclusion that the current data are not sufficient to justify the claim of the existence of such a syndrome. The low specificity of the observed PET and especially SPECT-findings makes it very difficult to establish a cause-result relationship and therefore makes the use of these methods in legal trials on this issue doubtful.

Humans↗
PubMed1999

[Imaging of secondary pulmonary changes in central bronchial carcinomas by F-18-FDG PET].

AIM: The presented study was performed in order to evaluate the potential interference of secondary pulmonary changes (dystelectasis, retention pneumonia) with bronchial carcinomas in F-18-FDG-PET. METHOD: A retrospective analysis of F-18-FDG-findings in 33 patients with bronchial carcinoma (staging) was performed. Seven out of fourteen patients with central tumor localisation had secondary pulmonary changes (thorax-x-ray, CT), which were classified as dystelectasis or atelectasis in five cases and as retention pneumonia in two cases. RESULTS: Whereas dystelectasis and atelectasis without clinical signs of infection showed only mild to moderate FDG-accumulation (SUV 1.0-2.5; mean: 1.74), an intense FDG-uptake in the two cases with retention pneumonia (SUV 8.4 and 5.5) was observed. Despite of the typical wedge-like shape of pneumonia, differentiation between bronchial carcinoma and pneumonia can be a problem. CONCLUSION: We suggest, that an antibiotic treatment in patients with known retention pneumonia should be performed prior to the PET-scan in order to reduce the interference of inflammatory changes.

Aged↗
PubMed1998

Increase of glucose transporter densities (Glut1 and Glut3) during chronic administration of nicotine in rat brain.

Chronic infusion of nicotine is known to result in a distinct pattern of increases in local cerebral glucose utilization (LCGU). The present study addresses the question whether this increase in LCGU is paralleled by (1) a local increase in Glut1 and/or Glut3 glucose transporter densities and (2) a local increase in capillary density in the brain. Nicotine was infused by osmotic minipumps for one week. In cryosections of rat brains local densities of Glut1 (vascular) and Glut3 (neuronal) glucose transporters were measured by immunoautoradiographic methods whereas local capillary densities were determined by an immunofluorescent method. Densities of glucose transporters Glut1 and Glut3 were increased in 12 of the 27 structures investigated. Glut1 was elevated in four additional structures and Glut3 in two more structures. Comparison of the changes in transporter densities with the changes of LCGU measured in a previous study during chronic nicotine infusion showed that LCGU was also elevated in most of these structures. In contrast, capillary density remained unchanged in all structures investigated. It is concluded that one week of nicotine infusion is sufficient to raise the densities of Glut1 and Glut3 glucose transporters predominantly in those structures in which LCGU is elevated. The unchanged capillary density under these conditions indicates an increased density of Glut1 transporters per capillary.

Animals↗
PubMed1998

[Clinical value of positron emission tomography in neuromedicine. Position paper on results of an interdisciplinary consensus conference].

To date, positron emission tomography (PET) is the most powerful method for the in-vivo investigation of human brain metabolism. Besides extensive application of this technology in the neurosciences, PET is also being increasingly used as a clinical tool. However, despite its acceptance in clinical practice a major obstacle is its high costs. The present article reviews the literature on the clinical use of PET in neurology, neurosurgery, and psychiatry in order to substantiate the clinical indications for PET in these specialties as established by an interdisciplinary conference.

Brain Diseases↗
PubMed1998

D2-dopamine receptor occupancy measured by IBZM-SPECT in relation to extrapyramidal side effects.

The purpose of this study was to compare striatal D2 dopamine receptor occupancy of various typical neuroleptics and clozapine in relation to the occurrence of extrapyramidal side effects (EPS). Forty-four inpatients with schizophrenia, including 12 patients with schizodominant schizoaffective disorder, were evaluated using 123I-iodobenzamide (IBZM) and single photon emission computed tomography. Striatal D2 dopamine receptor occupancy was estimated by use of a striatal/frontal cortex ratio (ST/FC) of IBZM binding. Fourteen patients were neuroleptic-free and served as controls. Six patients were treated with clozapine and 24 patients were treated with various typical neuroleptics. ST/FC ratios in patients taking typical neuroleptics were significantly lower than those who were neuroleptic free or treated with clozapine. Patients with EPS had lower ST/FC ratios than those without EPS. A significant linear relationship between ST/FC ratios and severity of EPS estimated by the Simpson-Angus-Scale was established (r=-0.51, p=0.041).

Adult↗
PubMed1998

Remission of bone metastases after combined chemotherapy and radionuclide therapy with Re-186 HEDP.

A patient with disseminated osseous metastases due to breast cancer reported multifocal pain. Because of persisting pain after a first cycle of chemotherapy, 1,295 MBq Re-186 HEDP was administered intravenously. Excellent pain relief was observed. Subsequently, the patient received further combined chemotherapy and Re-186 HEDP therapy and remained pain free. Tc-99m MDP bone imaging showed a significant regression of osseous metastases. It may be speculated that the combination of Re-186 HEDP and chemotherapy results in significantly increased palliation of metastatic bone disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Pathological regional cerebral blood flow in opiate-dependent patients during withdrawal: a HMPAO-SPECT study.

The aims of the present study were to investigate regional cerebral blood flow (rCBF) in heroin-dependent patients during withdrawal and to assess the relation between these changes and duration of heroin consumption and withdrawal data. The rCBF was measured using brain SPECT with 99mTc-HMPAO in 16 heroin-dependent patients during heroin withdrawal. Thirteen patients received levomethadone at the time of the SPECT scans. The images were analyzed both visually and quantitatively. A total of 21 hypoperfused brain regions were observed in 11 of the 16 patients. The temporal lobes were the most affected area, hypoperfusions of the right and left temporal lobe were observed in 5 and 5 patients, respectively. Three of the patients had a hypoperfusion of the right frontal lobe, 2 patients showed perfusion defects in the left frontal lobe, right parietal lobe and left parietal lobe. The results of the quantitative assessments of the rCBF were consistent with the results of the qualitative findings. The stepwise regression analysis showed a significant positive correlation (r = 0.54) between the dose of levomethadone at the time of the SPECT scan and the rCBF of the right parietal lobe. Other significant correlations between clinical data and rCBF were not found. The present results suggest brain perfusion abnormalities during heroin withdrawal in heroin-dependent patients, which are not due to the conditions of withdrawal.

Adult↗
PubMed1998

Results of the European multicenter study of radionuclide mammography with Tc-99m-MIBI.

In the European multicenter trial 246 female patients with suspicious mammographic result and/or breast mass were studied. In 253 lesions (195 palpable, 58 non-palpable) 165 malignant and 88 benign results were obtained histologically. All scans were evaluated centrally and institutionally. Central evaluation (per lesion) resulted in a sensitivity of 71% and a specificity of 69%. For palpable lesions, sensitivity was 83% in the central read and 91% in the institutional read. No difference was observed between invasive ductal and invasive lobular carcinoma. X-ray density had no influence on scintigraphic sensitivity. Sensitivity and specificity of mammography were 91% and 42%, respectively.

Breast Neoplasms↗
PubMed1998

rCBF SPECT and the acetazolamide test in the evaluation of dementia.

BACKGROUND: The diagnostic potential of 99mTc-HMPAO following systemic administration of the cerebral vasodilator acetazolamide (acetazolamide test) was evaluated using regional-cerebral-blood-flow (rCBF) SPECT in patients with Alzheimer's disease (AD) or with vascular-type of dementia (VD). METHODS: An initial, high-resolution SPELT study was performed with 99mTc-HMPAO, and after 2 days patients were re-evaluated with 99mTc-HMPAO following systemic administration of acetazolamide. Reconstructed SPELT slices were evaluated visually and semiquantitatively by a semiautomatic rCBF map method. RESULTS: Using 99mTc-HMPAO alone, a bilateral hypoperfusion was found in the temporal and/or parietal regions in 33% (6/18) of VD patients and in 70% (23/33) of AD patients. The vascular reserve capacity, as determined with the acetazolamide test, was not impaired in 22% of the VD patients but in 76% of the AD patients. The differences in the perfusion patterns between VD and AD patients were statistically different (p < 0.01, Fischer's exact test). Of the 6 VD patients with hypoperfusion (bilateral temporal and/or parietal), 4 had a decreased vascular reserve capacity as determined in the acetazolamide test. Decreased reserve capacity was found in only 4 out of 25 patients with AD. CONCLUSIONS: The acetazolamide test is helpful in rCBF SPECT to differentiate VD from AD.

Journal Article↗
PubMed1998

Redifferentiation therapy with retinoic acid in follicular thyroid cancer.

We report on a patient with a follicular Hurthle cell carcinoma in whom distant metastases were initially radioiodine negative or only weakly positive. Redifferentiation therapy with 13-cis retinoic acid induced a significant radioiodine uptake in metastatic tissue. Thyroglobulin (Tg) immunostaining and autoradiography of a bone metastasis in the right femur, which was initially radioiodine negative, proved Tg synthesis, combined with iodine incorporation into tumor cells. Glucose metabolism in metastases was partially increased and partially unchanged after redifferentiation therapy. The distinct increase of serum Tg after retinoic acid treatment was interpreted as a functional sign of redifferentiation.

Adenocarcinoma↗
PubMed1998

Redifferentiation therapy-induced radioiodine uptake in thyroid cancer.

UNLABELLED: Due to a dedifferentiation of tumor cells, some thyroid carcinomas lose their capability for radioiodine (RI) concentration. This phenomenon is associated with a worse prognosis and prevents effective treatment. Retinoic acid (RA) is known to induce redifferentiation in various kinds of tumors and has been used recently in thyroid cancer. METHODS: Twelve patients (9 women, 3 men) with 6 papillary, 4 follicular and 2 mixed-cell type tumors (including 4 Hurthle cell carcinomas) were treated orally with RA (dose: 1.18 +/- 0.37 mg/kg body weight) for at least 2 mo before RI therapy. None of the patients could be treated with any other modality (RI, surgery, external radiation) when RA administration was started. Initially, clinically important tumor sites did not take up significant amounts of RI. Changes of RI uptake and thyroglobulin (Tg) serum values were determined. Glucose metabolism was followed with fluorodeoxyglucose (FDG) PET imaging in 10 patients before and in 5 patients after RA treatment. RESULTS: In 2 patients, a significant RI uptake was induced by RA, and in another 3 patients a faint RI uptake was achieved (responder group). In 7 patients, no change of RI uptake was observed (nonresponder group). Median Tg was increased from 105-840 microg/liter during RA therapy in the responder group, which was significantly higher than the nonresponder group (173-134 microg/liter). FDG PET was positive in all 10 patients before RA therapy. PET showed variable patterns of changes (increase/decrease/disappearance) in glucose consumption related to RA response. CONCLUSION: RA can induce RI uptake in some patients with RI negative thyroid carcinoma tumor sites. Response to RA is associated with a significantly higher increase of Tg, suggesting that a restoration of Tg synthesis can be addressed as a redifferentiation parameter in these patients.

Adenocarcinoma, Follicular↗
PubMed1998

Functional imaging of Hodgkin's disease with FDG-PET and gallium-67.

We report a case of Hodgkin's lymphoma (Stage I B) which was studied using Ga-67-scintigraphy as well as whole body FDG-PET. Ga-67-scintigraphy detected a slightly increased uptake in the paraaortic and pelvic lymph nodes. However, FDG-PET was able to localize a much larger number of affected foci with a high glucose utilization rate in the right and left paraaortal regions, in the middle of the epigastrium, in the right and left parailiacal regions and one focus in the left upper mediastinum. Our experiences give rise to the assumption that FDG-PET ist significantly superior to gallium scintigraphy in Hodgkin's disease. Whole body FDG-PET can result in an upstaging of the patient and has therefore a major impact on the therapeutic management.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Inhibitory effects of mesial temporal partial seizures onto frontal neocortical structures.

PURPOSE: A retrospective evaluation of the ictal temporal tracer uptake and the perfusion pattern in other neo- and subcortical structures was performed to define typical extratemporal changes of rCBF that might further aid the differentiation of temporal and extratemporal seizures. METHOD: Ictal and interictal rCBF brain SPECT studies were done in 17 patients with seizures of mesial temporal onset according to scalp electroencephalography (EEG) and electrocorticography (ECoG) using 99mTc-ECD. Except for hippocampal sclerosis/atrophy, which was found in 11/17 patients, no morphologic anomalies were detected by MRI. Ictal tracer injections were given immediately after the onset of the seizure according to continuous video-EEG monitoring. The injection latency was two to twenty seconds. The data acquisition was done 45 minutes after the tracer injection using an annular crystal system (Ceraspect, DSI). In 15 patients a semiquantitative ROI-analysis of the tracer uptake in temporal and frontal regions could be obtained. RESULTS: All ictal studies correctly localised the affected temporal lobe. A detection of the epileptogenic focus itself was successful in 59% of patients while in the remaining patients the maximum of tracer uptake was not found to be located in the mesial temporal lobe only. In contrast to all other cerebral structures, only within the ipsilateral basal frontal cortex a frequent reaction to the temporal seizure was found. The basal frontal cortex ipsilateral to the affected temporal lobe showed a reduction of tracer uptake between the ictal and interictal study in 82% of patients which was semiquantitatively significant using a paired t-test (p < 0.05). Other neo- or subcortical structures showed inconsistent results. CONCLUSION: Secondary involvement of neocortical temporal structures in ictal rCBF-SPECT with 99mTc-ECD occurs early and focal maxima of tracer uptake within the temporal lobe do not necessarily represent the epileptogenic focus itself. Seizures of mesial temporal origin did not activate but frequently depressed the ipsilateral basal frontal tracer uptake during the early ictal phase. This phenomenon may account for some aspects of the clinical appearance of mesial temporal seizures.

Adolescent↗
PubMed1997

Comparison of fluorine-18 fluorodeoxyglucose positron emission tomography and technetium-99m methoxyisobutylisonitrile scintimammography in the detection of breast tumours.

The aim of this study was to compare, in breast cancer patients, the diagnostic accuracy of positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) and scintimammography (SMM) using technetium-99m methoxyisobutylisonitrile (MIBI). A total of 20 patients (40 breasts with 22 lesions) were evaluated serially with MIBI and, on the following day, with FDG. For SMM, planar and single-photon emission tomography imaging in the prone position was performed starting at 10 min following the injection of MIBI (740 MBq). For PET, scans were acquired 45-60 min after the injection of FDG (370 MBq) and attentuation correction was performed following transmission scans. Results from SMM and PET were subsequently compared with the histopathology results. True-positive results were obtained in 12/13 primary breast cancers (mean diameter=29 mm, range 8-53 mm) with both FDG and MIBI. False-negative results were obtained in two local recurrences (diameter <9 mm) with both FDG and MIBI. In benign disease, FDG and MIBI did not localize three fibrocystic lesions, two fibroadenomas and one inflammatory lesion (true-negative), but both localized one fibroadenoma (false-positive). Collectively, the results demonstrate a sensitivity of 92%, and a specificity of 86%, for primary breast cancer regardless of whether FDG or MIBI was used. In contrast to MIBI scintigraphy, FDG PET scored the axillae correctly as either positive (metastatic disease) or negative (no axillary disease) in all 12 patients. The tumour/non-tumour ratio for MIBI was 1.97 (range 1.43-3.1). The mean standard uptake value (SUV) for FDG uptake was 2.57 (range 0.3-6.2). The diagnostic accuracy of SMM was equivalent to that of FDG PET for the detection of primary breast cancer. For the detection of in situ lymph node metastases of the axilla, FDG seems to be more sensitive than 99mTc-MIBI.

Axilla↗
PubMed1997

Comparison of 18FDG-PET with 131iodine and 99mTc-sestamibi scintigraphy in differentiated thyroid cancer.

18Fluorine-fluorodeoxyglucose (FDG) positron-emission tomography (PET) has emerged as a useful method in various fields of oncology. The aim of the present study was to evaluate the clinical significance of this technique in differentiated thyroid carcinoma and to compare the results with other imaging modalities, particularly with whole-body 131iodine scintigraphy (WBS) and hexakis (2-methoxyisobutylisonitrile) (99m)technetium (I) scintigraphy (MIBI). Whole-body PET imaging using FDG was performed in 54 patients. There were 39 patients with papillary tumors and 15 patients with follicular tumors (including 3 Hürthle-cell carcinomas). Primary tumor stage (pT) was pT1 in 5 cases, pT2 in 19 cases, pT3 in 2 cases, pT4 in 24 cases, and unknown in 4 cases, respectively. Finally, for each case an overall clinical evaluation was done including histology, cytology, thyroglobulin level, sonography, computed tomography, magnetic resonance imaging, and subsequent clinical course, to allow a comparison with functional imaging results. Compared with WBS, FDG-PET gave different results in the majority of cases with recurrence/metastases (11 FDG-true-positive/WBS-negative tumor sites and 8 WBS-true-positive/FDG-negative tumor sites). In 7 patients with recurrence/metastases, FDG-PET and WBS gave corresponding results (10 sites). In 28 patients, FDG-PET and WBS were normal (including 2 false-negative cases). MIBI was performed in 44 cases. FDG-PET was better correlated to MIBI (congruent positive results in 13 tumor sites) than to WBS. Compared with MIBI, FDG-PET was superior in 5 cases (including 3 patients with distant metastases). Two FDG-negative/MIBI-positive tumors were observed. Different tracer uptake mechanisms have to be considered regarding "nonspecific" tumor imaging with FDG-PET or MIBI. Nevertheless, since spatial resolution with respect to tomographic imaging is inferior with single photon emission computer tomography (SPECT) using MIBI, the observed higher sensitivity of PET might be due to the higher spatial resolution of this method. As far as grading could be obtained, FDG-PET seemed to be more sensitive than WBS in high-grade tumors, whereas WBS was positive predominantly in low-grade carcinomas, although statistical significance could not be reached. The results prove the clinical usefulness of FDG-PET and MIBI for detection of 131iodine-negative tumor tissue in differentiated thyroid cancer.

Adult↗