Relative quantification of indium-111 pentetreotide and gallium-68 DOTATOC uptake in the thyroid gland and association with thyroid pathologies

BACKGROUND

Recent data suggest that increased somatostatin receptor (SSTR) expression is detectable in several thyroid diseases. This raises the question as to the specificity and pathophysiologic relevance of these findings. Therefore, we systematically evaluated Indium-111 (In-111) pentetreotide scintigraphies and Gallium-68 (Ga-68) DOTA-Phe(1)-Tyr(3)-Octreotide (DOTATOC) positron emission tomography (PET) scans for thyroid radiotracer uptake.

METHODS

Relative binding of In-111 pentetreotide in the thyroid was measured by region of interest (ROI) technique in 4-hour and 24-hour post-injection (p.i.) planar images of 73 patients undergoing In-111 pentetreotide scintigraphy. Ga-68 DOTATOC PET scans of 77 patients were analyzed by ROI technique applied to coronal slices of 1 cm (0.39 inch) thickness with highest uptake in the thyroid region.

RESULTS

A basal indium In-111 and Ga-68 DOTATOC uptake was found in normal thyroid glands. Hot nodules, disseminated thyroid autonomy, and most cases of active Hashimoto's disease as well as goiters and nodular thyroids showed increased In-111 pentetreotide and/or Ga-68 DOTATOC uptake. Higher relative In-111 pentetreotide uptake in the 24-hour p.i. images as compared to the 4-hour p.i. images except for patients after thyroidectomy indicates specific receptor binding in the thyroid.

CONCLUSIONS

The increased In-111 pentetreotide and Ga-68 DOTATOC uptake in active Hashimoto's disease is most likely related to the lymphocytic infiltration of the thyroid. However, the physiologic or pathophysiologic relevance of the increased In-111 pentetreotide and Ga-68 DOTATOC uptake in normal thyroid glands, hot and cold nodules, and goiters and nodular thyroids remain to be determined.

Whole-body MRI for primary evaluation of malignant disease in children

OBJECTIVE

The aim of this study was to compare diagnostic accuracy of whole-body (WB) MRI to a combined reference standard of conventional cross-sectional imaging methods and FDG-PET in the detection of malignant disease spread in children.

MATERIALS AND METHODS

24 children (age between 5 and 18 years) with malignant diseases (mainly Hodgkin's lymphoma and different types of sarcoma) initially examined with conventional cross-sectional imaging methods (ultrasound, computed tomography, or magnetic resonance imaging) were examined prospectively with whole-body MRI (1.5T) and FDG-PET. Studies were read by two nuclear medicine physicians (FDG-PET) and two radiologists (WB-MRI) independently in a blinded manner and each study type was evaluated in consensus. The reference standard was defined as pathological lesions detected in the same location both in FDG-PET and another conventional cross-sectional imaging method.

RESULTS

Overall 190 lesions were detected by WB-MRI and 155 lesion were found by FDG-PET. 106 lesions fulfilled the criteria of the reference standard (42 osseous and 64 extraosseous lesions) from which 102 were detected by WB-MRI (sensitivity of 96%). All bone lesions were detected and extra-skeletal lesions were identified with a sensitivity of 93.8%. Overall 88 lesions detected by WB-MRI were not part of the reference standard from which 33 were lesions of the peripheral skeleton not imaged by conventional cross-sectional imaging studies. 4 lesions of the reference standard were not identified by WB-MRI which were all lymph nodes.

CONCLUSION

WB-MRI is a radiation free imaging technique with high sensitivity for the detection of malignant disease spread in particular beneficial for children. In patients with suspected bone lesions it should be considered for initial disease evaluation prior to specific and regional imaging methods to reduce the overall number of imaging examinations and radiation exposure.

[Position paper nuclear cardiology: update 2008]

Nuclear cardiology is well established in clinical diagnostic algorithms for many years. This is an update 2008 of the first common position paper of the German Association of Nuclear Medicine and the German Association of Cardiology, Heart and Circulation Research published in 2001 aiming at an overview of state-of-the-art scintigraphic methods.

Guidelines for 18F-FDG PET and PET-CT imaging in paediatric oncology

OBJECTIVE

The purpose of these guidelines is to offer to the nuclear medicine team a framework that could prove helpful in daily practice. These guidelines contain information related to the indications, acquisition, processing and interpretation of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in paediatric oncology. The Oncology Committee of the European Association of Nuclear Medicine (EANM) has published excellent procedure guidelines on tumour imaging with (18)F-FDG PET (Bombardieri et al., Eur J Nucl Med Mol Imaging 30:BP115-24, 2003). These guidelines, published by the EANM Paediatric Committee, do not intend to compete with the existing guidelines, but rather aim at providing additional information on issues particularly relevant to PET imaging of children with cancer.

CONCLUSION

The guidelines summarize the views of the Paediatric Committee of the European Association of Nuclear Medicine. They should be taken in the context of "good practice" of nuclear medicine and of any national rules, which may apply to nuclear medicine examinations. The recommendations of these guidelines cannot be applied to all patients in all practice settings. The guidelines should not be deemed inclusive of all proper procedures or exclusive of other procedures reasonably directed to obtaining the same results.

Deletion of glucose transporter GLUT8 in mice increases locomotor activity

Transport of glucose into neuronal cells is predominantly mediated by the glucose transporters GLUT1 and GLUT3. In addition, GLUT8 is expressed in some regions of the brain. By in situ hybridization we detected GLUT8-mRNA in hippocampus, thalamus, and cortex. However, its cellular and physiological function is still unknown. Thus, GLUT8 knockout (Slc2a8^−/−) mice were used for a screening approach in the modified hole board (mHB) behavioral test to analyze the role of GLUT8 in the central nervous system. Slc2a8^−/− mice showed increased mean velocity, total distance traveled and performed more turns in the mHB test. This hyperactivity of Slc2a8^−/− mice was confirmed by monitoring locomotor activity in the home cage and voluntary activity in a running wheel. In addition, Slc2a8^−/− mice showed increased arousal as indicated by elevated defecation, reduced latency to the first defecation and a tendency to altered grooming. Furthermore, the mHB test gave evidence that Slc2a8^−/− mice exhibit a reduced risk assessment because they performed less rearings in an unprotected area and showed significantly reduced latency to stretched body posture. Our data suggest that behavioral alterations of Slc2a8^−/− mice are due to dysfunctions in neuronal processes presumably as a consequence of defects in the glucose metabolism.

[Myocardial perfusion scintigraphy 2006 in Germany. Results of the query and current status]

AIM

This second survey was to deliver further information on myocardial perfusion scintigraphy (MPS) in Germany in 2006.

METHOD

351 questionnaires were evaluated: 207 private practices (PP), 117 hospitals (HO), 27 from university hospitals (UH).

RESULTS

MPS of 106 331 patients were reported, 85% were investigated with (99m)Tc-perfusion tracers. 74% [2005 = 72%] were performed in PP, 17% [2005 = 15%] in HO and 9% [2005 = 13%] in UH. PP, which participated in 2005 and 2006, demonstrated an increase by 3,9% (HO 0%, UH - 13,0%). The type of stress was pharmacological in 27% [2005 = 22%]; 54% adenosine (of these 29% with exercise), 37% dipyridamole (of these 56% with exercise), and 9% dobutamine. Gated SPECT was performed in 42% [2005 = 36%] of all rest- and in 39% [2005 = 32%] of all stress MPS. An attenuation correction was used by 69 [2005 = 78] institutions. 40% of all MPS were performed in patients suspected to have CAD. 24% of all institutions reported changes in the use of MPS by competing methods.

CONCLUSION

There is a small increase of MPS between 2005 and 2006 despite competing methods. Gated SPECT has experienced more acceptance. Suspicion of CAD is an important indication of MPS. In order to tap the full potential of MPS a gated SPECT should be performed routinely.

[Myocardial perfusion scintigraphy in Germany. Results of the 2005 query and current status]

The working group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine (DGN), in cooperation with the working group Nuclear Cardiology of the German Cardiac Society (DGK), decided to conduct a national survey on myocardial perfusion scintigraphy (MPS).

METHOD

A questionnaire to evaluate MPS for the year 2005 was sent.

RESULTS

346 completed questionnaires had been returned (213 private practices, 99 hospitals and 33 university hospitals). MPS of 112 707 patients were reported with 110 747 stress and 95 878 rest studies. The majority (>75%) was performed with (99m)Tc-MIBI or tetrofosmin. (201)Tl stress-redistribution was used in 22 637 patients (20%). The types of stress were exercise in 78%, vasodilation with adenosine or dipyridamol in 21% and dobutamine in 1%. 99.97% of all MPS were SPECT studies. Gated SPECT was performed in 36% of the stress and in 32% of the rest studies. An attenuation correction was used in 21%. 29 institutions (8%) performed gated SPECT (stress and rest) and attenuation correction. 47% of all MPS were requested by ambulatory care cardiologists, 17% by internists, 12% by primary care physicians, 21% by hospital departments and 2% by others.

CONCLUSION

In Germany, MPS is predominantly performed with (99m)Tc-perfusion agents. The common type of stress is ergometry. Gated SPECT and attenuation correction do not yet represent standards of MPS practice in Germany, which indicates some potential of optimization.

[Efficient diagnosis of pathological fractures]

Pathological fractures are defined as fractures, which appear at diseased and mechanically weakened bones due to systemic or local processes. Their frequency is below 5%. This study demonstrates typical results and diagnostic criteria of pathological fractures. It will be shown, how diagnostic analysis is supposed to be performed to recognize pathological fractures. Based just on the X-ray image, diagnostic algorithms should provide all tools required for the radiologist to create a final diagnosis or to refer to other appropriate imaging modalities followed by a correct diagnosis and, if necessary, to allow interdisciplinary causal therapies.

Management and outcome in patients with Klatskin-mimicking lesions of the biliary tree

The preoperative and even intraoperative differentiation between benign and malignant strictures at the hepatic hilum remains difficult. The aim of this study was to assess clinical, radiologic, intraoperative, and histopathologic findings; surgical treatment; and outcome of patients with Klatskin mimicking benign lesions. Of 49 consecutive patients who were operated on the initial preoperative radiologic diagnosis of hilar adenocarcinoma (Klatskin tumor), 7 (14%) had benign conditions after final histopathologic diagnosis. Pretreatment work-up, therapy, and outcome of these patients were analyzed. Based on preoperative clinical symptoms, imaging assessment, and CA19-9 values, all seven patients were classified as having malignant neoplasms. At laparotomy, the tumors of six patients were judged to be malignant. Five patients underwent hilar resection and concomitant liver resection, and two patients underwent hilar resection alone. There were no operative deaths. The definitive histopathologic examination showed severe cholangitis with extensive periductal fibrosis in all patients. After a median follow-up of 32 months, all patients are well. Clinical presentation and imaging assessment were similar for Klatskin tumors and benign fibrosing disease; therefore, an aggressive resectional approach is justified in any patient with suspicious obstruction of the liver hilum.