Complementarity between 18F-FDG PET/CT and Ultrasonography or Angiography in Carotid Plaque Characterization

BACKGROUND AND PURPOSE: To estimate clinical roles of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) versus angiography and ultrasonography in carotid plaque characterization. METHODS: We characterized two groups of patients with recently (<1 month) symptomatic (n=14; age=71.8+/-8.6 years, mean+/-SD) or chronic (n=13, age=68.9+/-9.0 years) carotid stenosis using a battery of imaging tests: diffusion magnetic resonance (MR) imaging, MR or transfemoral angiography, duplex ultrasonography (DUS), and carotid FDG-PET/computed tomography. RESULTS: The degree of angiographic stenosis was greater in patients with recently symptomatic carotid plaques (67.5+/-21.5%) than in patients with chronic carotid plaques (32.4+/-26.8%, p=0.001). Despite the significant difference in the degree of stenosis, lesional maximum standardized uptake values (maxSUVs) on the carotid FDG-PET did not differ between the recently symptomatic (1.56+/-0.53) and chronic (1.56+/-0.34, p=0.65) stenosis groups. However, lesional-to-contralesional maxSUV ratios were higher in the recently symptomatic stenosis group (113+/-17%) than in the chronic stenosis group (98+/-10%, p=0.017). The grayscale median value of the lesional DUS echodensities was lower in the recently symptomatic stenosis group (28.2+/-10.0, n=9) than in the chronic stenosis group (53.9+/-14.0, n=8; p=0.001). Overall, there were no significant correlations between angiographic stenosis, DUS echodensity, and FDG-PET maxSUV. Case/subgroup analyses suggested complementarity between imaging modalities. CONCLUSIONS: There were both correspondences and discrepancies between the carotid FDG-PET images and DUS or angiography data. Further studies are required to determine whether FDG-PET could improve the clinical management of carotid stenosis.

A Case of Monoclonal Gammopathy in Extranodal Marginal Zone B-cell Lymphoma of the Small Intestine / 대한진단검사의학회지

Monoclonal gammopathy occurs in one-third of the patients with mucosa-associated lymphoid tissue lymphoma (MALT lymphoma). However, monoclonal gammopathy has been rarely reported in Korea. Paraprotenemia accompanying MALT lymphoma is strongly correlated with involvement of the bone marrow, and this involvement leads to the progression of the disease. Here, we present a case of a 66-yr-old man diagnosed with IgM monoclonal gammopathy and stage IV extranodal marginal zone lymphoma of the small intestine, with the involvement of the bone marrow.

Nuclear Imaging of Cellular Proliferation / 대한핵의학회잡지

Tumor cell proliferation is considered to be a useful prognostic indicator of tumor aggressiveness and tumor response to therapy, but in vitro measurement of individual proliferation is complex and tedious work. PET imaging provides a noninvasive approach to measure tumor growth rate in situ. Early approaches have used 18F-FDG or methionine to monitor proliferation status. These 2 tracers detect changes in glucose and amino acid metabolism, respectively, and therefore provide only an indirect measure of proliferation status. More recent studies have focused on DNA synthesis itself as a marker of cell proliferation. Cell lines and tissues with a high proliferation rate require high rates of DNA synthesis. [11C]Thymidine was the first radiotracer for noninvasive imaging of tumor proliferation. The short half-life of 11C and rapid metabolism of [11C]thymidine in vivo make the radiotracer less suitable for routine use. Halogenated thymidine analogs such as 5-iodo-2-deoxyuridine (IUdR) can be successfully used as cell proliferation markers for in vitro studies because these compounds are rapidly incorporated into newly synthesized DNA. IUdR has been evaluated as a potential in vivo tracer in nuclear medicine, but the image quality and the calculation of proliferation rates are impaired by its rapid in vivo degradation. Hence, the thymidine analog 3'-deoxy-3'-18F-fluorothymidine (FLT) was recently introduced as a stable proliferation marker with a suitable nuclide half-life and stable in vivo. [18F]FLT is phosphorylated to 3-fluorothymidine monophosphate by thymidine kinase 1 and reflects thymidine kinase 1 activity in proliferating cell. [18F]FLT PET is feasible in clincal use and well correlates with cellular proliferation. Choline is a precursor for the biosynthesis of phospholipids (in particular, phosphatidylcholine), which is the essential component of all eukaryotic cell membranes and [11C]choline, which is a new marker for cellular proliferation.

Foreign Body Granuloma and Breast Cancer in the Augmented Breast: Mammography, US, MRI, and FDG-PET

The mammographic or physical evaluation of breast parenchymal abnormalities in the presence of radiopaque implants or silicone injections is difficult; mammography often fails to discriminate between breast cancer and a radiopaque dense breast. Although the sonographic evaluation of a palpable mass in an augmented breast may be impaired by the presence of posterior acoustic shadowing, the modality may be helpful in evaluating such masses, and dynamic contrast-enhanced MR imaging facilitates differentiation. FDG-PET is a possible alternative diagnostic tool for the evaluation of parenchymal lesions under these circumstances, but its drawbacks are its high cost and limited availability. The sensitivity and specificity of both FDG-PET and MRI can be improved by correlating their findings with those of radiological studies, and through an awareness of potential false-negative and false-positive causes.

Prospective Study of 162 Sentinel Lymph Node Biopsies in Breast Cancer: Usefulness of Ultrasonography in Patients Selection / 한국유방암학회지

PURPOSE: Sentinel lymph node (SLN) biopsy has been widely used in the management of melanoma and breast cancer. The aims of this study were (1) to compare the results obtained with the different injection, intraoperative sentinel node evaluation, and postoperative evaluation; and (2) to determine the reliability of SLN to predict the regional lymph node status. METHODS: We prospectively studied selected 162 female primary breast cancer patients from Jun. 1999 to Apr. 2003. For identification of sentinel lymph node, Tc99m-antimony trisulfate was used as a tracer with two injection methods and SLN biopsy using a gamma-detection probe was done after breast lymphoscintigraphy. Frozen section biopsy or touch-print cytology was done for intraoperative evaluation. If a SLN biopsy was free of metastasis by permanent hematoxylin and eosin (H&E) staning, Immunohistochemical staning using pan-cytokeartin was done to detect micrometastasis. RESULTS: SLN was detected 96.2% with lymphoscintigraphy, 100% with gamma-probe. The mean number of resected SLN was 1.83 0.95 and all SLN located in axilla. The false-negative rate of SLN biopsy was 5.6%, and there was no statistical difference in intraoperative frozen biopsy vs touch-print cytology, injection methods, tumor size, number of examined SLN (P> 0.1). But a significant differences exist in preoperative ultrasonography for axillary lymph node status (P=0.014). Adding the ultrasonographic findings to the patient-selection criteria, the false-negative rates decreased to 2.9%. CONCLUSION: We suggest that ultrasonography should be included into the patient selection criteria to reduce the false- negative rate in sentinel node biopsy of breast cancer.

Effect of LiCl on Iodine Kinetics in Thyroid Cancer Cell Lines Transduced by Recombinant Adenovirus Containing Sodium Iodide Symporter(NIS) Gene / 대한내분비학회지

BACKGROUND: Lithium is known to increase the retention of iodide in the thyroid gland, or in well differentiated thyroid cancer tissue. The effects of lithium on the function of the sodium iodide symporter (NIS) protein, especially when the lithium is increased in the retention of iodide in NIS-producing cells, the effect of lithium, on the kinetics of undifferentiated thyroid cancer cells transduced by a recombinant adenovirus containing the NIS gene, were checked. METHOD: Human NIS cDNA was inserted into pAxCAwt, a recombinant adenoviral cosmid vector, where the E1 & E2 genes have been deleted, making Rad-hNIS, which was propagated in 293 cells. The iodide uptake was evaluated by the 125I uptake assay in the undifferentiated thyroid cancer cells, ARO, FRO and NPA, following the infection with Rad-hNIS (1 or 10 MOI) in the presence, or absence, of LiCl at optimized concentrations. The iodide efflux was evaluated by the 125I efflux assay, for 1 hour, in the same cells expressing the NIS in the presence, or absence, of LiCl. Similar experiments were performed in the normal thyroid cell line, FRTL-5, cultured in 6H5 media. RESULTS: LiCl, at concentrations over 1.0mM, caused a significant decrease in the cell viability, as evaluated by trypan blue dye exclusion, in a dose dependent manner. When infected with Rad-hNIS, the iodide uptake was not affected by the LiCl in the ARO or NPA cells. However, LiCl(0.1and 1.0mM) increased the iodide uptake by 50 to 100%(vs. control) in the Rad-hNIS transduced FRO cells. In the Rad-hNIS transduced FRO cells, the iodide was released rapidly from the cells, with only 20.7+/-4.8% of the iodide uptake remaining at 1 hour, which was no different in the presence of LiCl (24.5+/-7.9%). The iodide efflux was not affected by the LiCl in the FRTL-5 cells cultured in the presence of TSH. CONCLUSION: These results suggest that the lithium-induced iodide retention in the thyroid gland, or in well differentiated thyroid cancer tissue, is not caused by the effect of the lithium on the NIS function, or the function of proteins or channels, involved in iodide transport via cell membranes. Although the iodide uptake can be markedly increased by the expression of NIS, with the transduction of Rad-hNIS, in undifferentiated thyroid cancer cells, the iodide taken up is rapidly released from the cells. A method for inducing the iodide retention in the cell should be elucidated in order to render the NIS gene therapy effective.

Prediction of Salvaged Myocardium in Patients with Acute Myocardial Infarction after Primary Percutaneous Coronary Angioplasty using early Thallium-201 Redistribution Myocardial Perfusion Imaging / 대한핵의학회잡지

PURPOSE: The amount of salvaged myocardium is an important prognostic factor in patients with acute myocardial infarction (MI). We investigated if early Tl-201 SPECT imaging could be used to predict the salvaged myocardium and functional recovery in acute MI after primary PTCA. MATERIALS AND METHODS: In 36 patients with first acute MI treated with primary PTCA, serial echocardiography and Tl-201 SPECT imaging (5.8+/-2.1 days after PTCA) were performed. Regional wall motion and perfusion were quantified with on 16-segment myocardial model with 5-point and 4-point scaling system, respectively. RESULTS: Wall motion was improved in 78 of the 212 dyssynergic segments on 1 month follow-up echocardiography and 97 on 7 months follow-up echocardiography, which were proved to be salvaged myocardium. The areas under receiver operating characteristic curves of Tl-201 perfusion score for detecting salvaged myocardial segments were 0.79 for 1 month follow-up and 0.83 for 7 months follow-up. The sensitivity and specificity of Tl-201 redistribution images with optimum cutoff of 40% of peak thallium activity for detecting salvaged myocardium were 84.6% and 55.2% for 1 month follow-up, and 87.6% and 64.3% for 7 months follow-up, respectively. There was a linear relationship between the percentage of peak thallium activity on early redistribution imaging and the likelihood of segmental functional improvement 7 months after reperfusion. CONCLUSION: Tl-201 myocardial perfusion SPECT imaging performed early within 10 days after reperfusion can be used to predict the salvaged myocardium and functional recovery with high sensitivity during the 7 months following primary PTCA in patients with acute MI.

Relationship between Brain Perfusion SPECT and MNSK Score in Dementia of Alzheimer`s Type - A statistical Parametric Mapping Analysis / 대한핵의학회잡지

No abstract available.

The Role of PET in Thyroid Cancer / 대한핵의학회잡지

No abstract available.

Role of Whole Body FDG-PET in the Diagnosis of Hidden Distant Metastasis before Liver Transplantation in Patients with Primary Liver Cancer / 대한핵의학회잡지

No abstract available.

Role of Whole Body FDG-PET in the Diagnosis of Hidden Distant Metastasis before Liver Transplantation in Patients with Primary Liver Cancer / 대한핵의학회잡지

No abstract available.

Brain F - 18 FDG PET for localization of epileptogenic zones in frontal lobe epilepsy ; visual assessment and statistical parametric mapping analysis / 대한핵의학회잡지

No abstract available.

Pattern of Cerebral Glucose Metabolism on F - 18 FDG Brain PET druing Vomiting and Symptom Free Periods in Cyclic Vomiting Syndrome / 대한핵의학회잡지

No abstract available.

Difference of Time Course of Functional Recovery after Revascularization According to Preoperative Reversibility of Perfusion Impairment in Ischemic Myocardial Dysfunction / 대한핵의학회잡지

No abstract available.

Correlation of GLUT-1 Expression and F-18-FDG Uptake on Positron Emission Tomography in Breast Carcinoma / 대한암학회지

PURPOSE: Fluorine-18-fluorodeoxyglucose (F-18-FDG) positron emission tomography (PET) has been proven to be useful in the detection of breast cancer. However, the degree of FDG uptake was variable. In this study, we evaluated the relationship between glucose transporter-1 (GLUT-1) expression with the FDG uptake in patients with breast cancer. MATERIALS AND METHODS: 15 patients with proven breast cancer underwent F-18-FDG PET. After surgical resection, anti-GLUT-1 immunohistochemical staining was performed in tumor tissues to measure the GLUT-1 expression. We evaluated the correlation between semi-quantitative FDG uptake by standardized uptake value (SUV) and GLUT-1 expression. RESULTS: In total 15 patients, there was no significant correlation between SUV and GLUT-1 expression. We separated the patients into two groups according to the tumor size. In the group of large tumor (short diameter > or =2 cm), there was no significant correlation. However, in the group of small tumor (short diameter <2 cm), there was a significant correlation between the FDG uptake and GLUT-1 expression (rho=0.812, p=0.047). CONCLUSION: GLUT-1 expression can influence the FDG uptake in the small breast cancers. For large breast cancers, other factors as well as GLUT-1 expression may influence the FDG uptake.

Quantification of Cerebrovascular Reserve Using Tc-99m HMPAO Brain SPECT and Lassen's Algorithm / 대한핵의학회잡지

PURPOSE: For quantitative estimation of cerebrovascular reserve (CVR), we estimated the cerebral blood flow (CBF) using Lassen's nonlinearity correction algorithm and Tc-99m HMPAO brain SPECT images acquired with consecutive acquisition protocol. Using the values of CBF in basal and acetazolamide (ACZ) stress states, CBF increase was calculated. MATERALS AND METHODS: In 9 normal subjects (age: 72+/-4 years), brain SPECT was performed at basal and ACZ stress states consecutively after injection of 555 MBq and 1,110 MBq of Tc-99m HMPAO, respectively. Cerebellum was automatically extracted as reference region on basal SPECT image using threshold method. Assuming basal CBF of cerebellum as 55 ml/100 g/min, CBF was calculated for every pixel at basal states using Lassen's algorithm. Cerebellar blood flow at stress was estimated comparing counts of cerebellum at rest and ACZ stress and Lassen's algorithm. CBF of every pixel at ACZ stress state was calculated using Lassen's algorithm and ACZ cerebellar count. CVR was calculated by subtracting basal CBF from ACZ stress CBF for every pixel. The percent CVR was calculated by dividing CVR by basal CBF. The CBF and percentage CVR parametric images were generated. RESULTS: The CBF and percentage CVR parametric images were obtained successfully in all the subjects. Global mean CBF were 49.6+/-5.5 ml/100g/min and 64.4+/-10.2 ml/100g/min at basal and ACZ stress states, respectively. The increase of CBF at ACZ stress state was 14.7+/-9.6 ml/100g/min. The global mean percent CVR was 30.7% and was higher than the 13.8% calculated using count images. CONCLUSION: The blood flow at basal and ACZ stress states and cerebrovascular reserve were estimated using basal/ACZ Tc-99m-HMPAO SPECT images and Lassen's algorithm. Using these values, parametric images for blood flow and cerebrovascular reserve were generated.

Influence of Gating and Attenuation-correction for Diagnostic Performance of Usual Rest/stress Myocardial Perfusion SPECT in Coronary Artery Disease / 대한핵의학회잡지

PURPOSE: Either gated myocardial perfusion SPECT or attenuation corrected SPECT can be used to improve specificity in the diagnosis of coronary artery disease. We investigated in this study whether gating or attenuation correction improved diagnostic performance of rest/stress perfusion SPECT in patients having intermediate pre-test likelihood of coronary artery disease. MATERIALS AND METHODS: Sixty-eight patients underwent rest attenuation-corrected T1-20l/dipyridamole stress gated attenuation-corrected Tc-99m-MIBI SPECT using an ADAC vertex camera (M:F=29:39, aged 59+/-12 years, coronary artery stenosis> or =70%. one vessel: 13, two vessel: 18, three vessel: 8, normal: 29). Using a five-point scale, three physicians graded the post-test likelihood of coronary artery disease for each arterial territory (1 normal, 2: possibly normal 3:equivocal, 4: possibly abnormal, 5: abnormal). Sensitivity, specificity and area under receiver-operating-characteristic curves were compared for each operator between three METHODS: (A) non-attenuation-corrected SPECT; (B) gated SPECT added to (A); and (C) attenuation-corrected SPECT added to (B). RESULTS: When grade 3 was used as the criteria for coronary artery disease, no differences in sensitivity and specificity were found between the three methods for each operator Areas under receiver- operating-characteristic curves for diagnosis of coronary artery disease revealed no differences between each modality (p>005). CONCLUSION: In patients at intermediate risk of coronary artery disease, gated SPECT and attenuation-corrected SPECT did not improve diagnostic performance.

Comparison of Diagnostic Performance between Interictal F-18-FDG PET and Ictal Tc-99m-HMPAO SPECT in Occipital Lobe Epilepsy / 대한핵의학회잡지

PURPOSE: Interictal F-18-fluorodeoxyglucose (FDG) PET and ictal Tc-99m-HMPAO SPECT are found to be useful in localizing epileptogenic zones in neocortical lateral temporal or frontal lobe epilepsy. We investigated whether interictal F-18-FDG PET or ictal Tc-99m-HMPAO SPECT was useful to find epileptogenic zones in occipital lobe epilepsy (OLE). MATERIALS AND METHODS: We reviewed patterns of hypometabolism in interictal F-18-FDG PET and of hyperperfusion in ictal Tc-99m-HMPAO SPECT in 17 OLE patients (mean age=27+/-6.8 year, M:F=10:7, injection time=30+/-17 sec). OLE was diagnosed based on invasive electroencephalography (EEG) study, surgery and post-surgical outcome (Engel class I in all for average 14 months). RESULTS: Epileptogenic zones were correctly localized in 9 (60%) out of 15 patients by interictal F-18-FDG PET. Epiletogenic hemispheres were correctly lateralized in 14 patients (93%). By ictal Tc-99m-HMPAO SPECT, epileptogenic hemispheres were correctly lateralized in 13 patients (76%), but localization was possible only in 3 patients (18%). Among patients who showed no abnormality with MR imaging and no correct localization with ictal Tc-99m-HMPAO SPECT, interictal F-18-FDG PET was helpful in 2 patients. CONCLUSION:: Ictal Tc-99m-HMPAO SPECT was helpful in lateralization but not in localization in OLE. Interictal F-18-FDG PET was helpful for localization of epileptogenic zones even in patients with ambiguous MR or ictal SPECT findings. Key KW: Occipital lobe epilepsy, Tc-99m-HMPAO, Ictal perfusion SPECT, F-18-FDG, PET, SPECT

Differential Diagnosis of Breast Mass and Staging of Breast Cancer Using F-18-FDG PET / 대한핵의학회잡지

PURPOSE: F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been proven to be useful in the differential diagnosis of breast mass and staging of breast cancer. This study assessed the diagnostic accuracy of F-18-FDG PET in the differentiation of breast mass and staging of breast cancer. MATERIALS AND METHODS: Total 42 patients who had breast mass underwent F-18-FDG PET (all female, 40+/-10 year old). We compared F-18 FDG PET results with pathologic findings in 24 patients RESULTS: In the differentiation of breast mass, sensitivity and specificity were 95% (19/20) and 77% (7/9) respectively. Three false positive cases were due to inflammation and one false negative patient had small tumor less than 1 cm. In the assessment of axillary lymph node status, sensitivity and specificity were 73% (8/11) and 100% (7/7) respectively. We found distant metastasis that were not suspected before F-18-FDG PET in 2 patients. CONCLUSION: F-18-FDG PET shows good diagnostic performance in differentiation of breast mass and staging of breast cancer.

Asymmetry of Medial and Lateral Tempora) Regional Glucose Metabolism in Temporal Lobe Epilepsy by F-18-FDG PET / 대한핵의학회잡지

PURPOSE: We investigated the difference of glucose metabolism of medial and lateral temporal lobes of patients with temporal lobe epilepsy (TLE) utilizing quantitative comparison of regional metabolic activities using asymmetric index. MATERIALS AND METHODS: We studied 19 pathologically proven mesial TLE and 25 lateral TLE patients. Lateral TLE patients were either normal on magnetic resonance imaging (cryptogenic: n=14) or had structural lesions (lesional: n=11). Asymmetric index (ASI) was calculated as [(ipsilateral-contralateral)/(ipsilateral+ contralateral)]x200. RESULTS: ASI of medial and lateral lobes of mesial TLE was decreased (-16.4+/-8.3 and -12.7+/-5.5, respectively). In cryptogenic lateral TLE, ASI of lateral temporal lobe was decreased (-11.8+/-4.7), whereas that of medial temporal lobe was not decreased (-4.6+/-6.3). ASI of medial lobe of lesional lateral TLE was -7.3+/-9.1, which was significantly different from that of mesial TLE (p<0.05). Patients with lesional lateral TLE had evident metabolic defects or decrease (ASI: -22+/-10.5) in lateral temporal lobe. While we could not find the difference of metabolic activity in lateral temporal lobes between cryptogenic lateral TLE and mesial TLE patients, the difference of metabolic activity was significant in medial temporal lobes which was revealed by ASI quantitation. CONCLUSION: Asymmetric decrease of metabolic activity in both medial and lateral temporal lobes indicates medial temporal epilepsy. Symmetry of metabolic activity in medial temporal lobe combined with asymmetry of that in lateral temporal lobe may give hints that the epileptogenic zone is lateral.