18F-FDG PET/CT Parameters Enhance MRI Radiomicsfor Predicting Human Papilloma Virus Status in Oropharyngeal Squamous Cell Carcinoma

Purpose@#Predicting human papillomavirus (HPV) status is critical in oropharyngeal squamous cell carcinoma (OPSCC) radiomics. In this study, we developed a model for HPV status prediction using magnetic resonance imaging (MRI) radiomics and18F-fluorodeoxyglucose ( 18F-FDG) positron emission tomography (PET)/computed tomography (CT) parameters in patients withOPSCC. @*Materials and Methods@#Patients with OPSCC who underwent 18F-FDG PET/CT and contrast-enhanced MRI before treatment between January 2012 and February 2020 were enrolled. Training and test sets (3:2) were randomly selected. 18F-FDG PET/CT parameters and MRI radiomics feature were extracted. We developed three light-gradient boosting machine prediction models using the training set: Model 1, MRI radiomics features; Model 2, 18F-FDG PET/CT parameters; and Model 3, combination of MRI radiomics features and 18F-FDG PET/CT parameters. Area under the receiver operating characteristic curve (AUROC) values were used to analyze the performance of the models in predicting HPV status in the test set. @*Results@#A total of 126 patients (118 male and 8 female; mean age: 60 years) were included. Of these, 103 patients (81.7%) were HPV-positive, and 23 patients (18.3%) were HPV-negative. AUROC values in the test set were 0.762 [95% confidence interval (CI), 0.564–0.959], 0.638 (95% CI, 0.404–0.871), and 0.823 (95% CI, 0.668–0.978) for Models 1, 2, and 3, respectively. The net reclassification improvement of Model 3, compared with that of Model 1, in the test set was 0.119. @*Conclusion@#When combined with an MRI radiomics model, 18F-FDG PET/CT exhibits incremental value in predicting HPV status in patients with OPSCC.

Development and Testing of a Machine Learning Model Using 18 F-Fluorodeoxyglucose PET/CT-Derived Metabolic Parameters to Classify Human Papillomavirus Status in Oropharyngeal Squamous Carcinoma

Objective@#To develop and test a machine learning model for classifying human papillomavirus (HPV) status of patients with oropharyngeal squamous cell carcinoma (OPSCC) using 18 F-fluorodeoxyglucose ( 18 F-FDG) PET-derived parameters in derived parameters and an appropriate combination of machine learning methods in patients with OPSCC. @*Materials and Methods@#This retrospective study enrolled 126 patients (118 male; mean age, 60 years) with newly diagnosed, pathologically confirmed OPSCC, that underwent 18 F-FDG PET-computed tomography (CT) between January 2012 and February 2020. Patients were randomly assigned to training and internal validation sets in a 7:3 ratio. An external test set of 19 patients (16 male; mean age, 65.3 years) was recruited sequentially from two other tertiary hospitals. Model 1 used only PET parameters, Model 2 used only clinical features, and Model 3 used both PET and clinical parameters. Multiple feature transforms, feature selection, oversampling, and training models are all investigated. The external test set was used to test the three models that performed best in the internal validation set. The values for area under the receiver operating characteristic curve (AUC) were compared between models. @*Results@#In the external test set, ExtraTrees-based Model 3, which uses two PET-derived parameters and three clinical features, with a combination of MinMaxScaler, mutual information selection, and adaptive synthetic sampling approach, showed the best performance (AUC = 0.78; 95% confidence interval, 0.46–1). Model 3 outperformed Model 1 using PET parameters alone (AUC = 0.48, p = 0.047) and Model 2 using clinical parameters alone (AUC = 0.52, p = 0.142) in predicting HPV status. @*Conclusion@#Using oversampling and mutual information selection, an ExtraTree-based HPV status classifier was developed by combining metabolic parameters derived from 18 F-FDG PET/CT and clinical parameters in OPSCC, which exhibited higher performance than the models using either PET or clinical parameters alone.

Prognostic value of complete metabolic response on 18F-FDG-PET/CT after three cycles of neoadjuvant chemotherapy in advanced high-grade serous ovarian cancer / 부인종양

Objective@#We investigated the prognostic value of complete metabolic response (CMR) on 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) after 3 cycles of neoadjuvant chemotherapy (NAC) in advanced high-grade serous ovarian cancer (HGSC). @*Methods@#PET/CT at baseline and after 3 cycles of NAC were performed; peak standardized uptakes were measured. PET parameters were compared with NAC parameter: cancer antigen-125 (CA-125) normalization before interval debulking surgery (IDS) and chemotherapy response score (CRS) to predict platinum-sensitivity. Kaplan-Meier analysis was used to determine correlations between PET parameters and survival. Prognostic factors were obtained by multivariate Cox regression analysis. @*Results@#Between 2007 and 2020, 102 patients were recruited: 19 (18.6%) were designated as CMR group and 83 (81.4%) as non-CMR group. CMR after 3 cycles of NAC showed the highest accuracy in predicting platinum-sensitivity (area under the curve [AUC]=0.729; 95% confidence interval [CI]=0.552–0.823; p=0.017), compared with CA-125 normalization before IDS (AUC=0.626; 95% CI=0.542–0.758; p=0.010) and CRS (AUC=0.613; 95% CI=0.490–0.735; p=0.080). CMR demonstrated better prognosis than non-CMR in progression-free survival (PFS) (median PFS, 23.9 months vs. 16.4 months; p=0.021) and overall survival (OS) (median OS, not reached vs. 69.7 months; p=0.025). In multivariate analysis, CMR was associated with a lower risk of recurrence (adjusted hazard ratio [aHR]=0.50; 95% CI=0.27–0.92; p=0.027) and death (aHR=0.23; 95% CI=0.05–0.99; p=0.048). @*Conclusion@#CMR after 3 cycles of NAC can be a prognostic factor for both recurrence and death in advanced HGSC.

KSNM60 in Cardiology: Regrowth After a Long Pause / 대한핵의학회잡지

The Korean Society of Nuclear Medicine (KSNM) is celebrating its 60th anniversary in honor of the nuclear medicine professionals who have dedicated their efforts towards research, academics, and the more comprehensive clinical applications and uses of nuclear imaging modalities. Nuclear cardiology in Korea was at its prime time in the 1990s, but its growth was interrupted by a long pause. Despite the academic and practical challenges, nuclear cardiology in Korea now meets the second leap, attributed to the growth in molecular imaging tailored for many non-coronary diseases and the genuine values of nuclear myocardial perfusion imaging. In this review, we describe the trends, achievements, challenges, and perspectives of nuclear cardiology throughout the 60-year history of the KSNM.

Early Assessment of Response to Neoadjuvant Chemotherapy with 18F-FDG-PET/CT in Patients with Advanced-Stage Ovarian Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The aim of this study was to evaluate the ability of sequential 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) after one cycle of neoadjuvant chemotherapy (NAC) to predict chemotherapy response before interval debulking surgery (IDS) in advanced-stage ovarian cancer patients. @*Materials and Methods@#Forty consecutive patients underwent 18F-FDG-PET/CT at baseline and after one cycle of NAC. Metabolic responses were assessed by quantitative decrease in the maximum standardized uptake value (SUVmax) with PET/CT. Decreases in SUVmax were compared with cancer antigen 125 (CA-125) level before IDS, response rate by Response Evaluation Criteria in Solid Tumors criteria before IDS, residual tumor at IDS, and I chemotherapy response score (CRS) at IDS. @*Results@#A 40% cut-off for the decrease in SUVmax provided the best performance to predict CRS 3 (compete or near-complete pathologic response), with sensitivity, specificity, and accuracy of 81.8%, 72.4%, and 72.4%, respectively. According to this 40% cut-off, there were 17 (42.5%) metabolic responders (≥ 40%) and 23 (57.5%) metabolic non-responders (< 40%). Metabolic responders had higher rate of CRS 3 (52.9% vs. 8.7%, p=0.003), CA-125 normalization (< 35 U/mL) before IDS (76.5% vs. 39.1%, p=0.019), and no residual tumor at IDS (70.6% vs. 31.8%, p=0.025) compared with metabolic non-responders. There were significant associations with progression-free survival (p=0.021) between metabolic responders and non-responders, but not overall survival (p=0.335). @*Conclusion@#Early assessment with 18F-FDG-PET/CT after one cycle of NAC can be useful to predic response to chemotherapy before IDS in patients with advanced-stage ovarian cancer.

Prognostic Value of Bone Marrow F-18 FDG Uptake in Patients with Advanced-Stage Diffuse Large B-Cell Lymphoma / 대한핵의학회잡지

Purpose@#We assessed prognostic implication of bone marrow uptake on baseline F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in patients with advanced-stage diffuse large B-cell lymphoma (DLBCL). @*Methods@#We retrospectively reviewed 140 patients with stage III and IV DLBCL, who underwent baseline F-18 FDG PET/CT at diagnosis. Bone marrow uptake on F-18 FDG PET/CT (BM FDG) was compared with findings on bone marrow biopsy (BMB), and patients were grouped based on these results: BMB-positive and BM FDG-positive (group 1), BMB-positive and BM FDG-negative (group 2), BMB-negative and BM FDG-positive (group 3), and BMB-negative and BM FDG-negative (group 4). The prognostic value of clinicopathologic factors and BM FDG for predicting progression-free survival (PFS) and overall survival (OS) was assessed using a Cox proportional hazards model. Differences in PFS and OS were examined by the Kaplan-Meier method. @*Results@#BMB was the only significant indicator in predicting PFS, and age, IPI score higher than 3, and BM FDG significantly predicted OS. Group 1 showed inferior PFS than group 2 (median PFS, 7.4 vs. 13.9 months; p = 0.04). In contrast, there was no significant difference either in PFS or OS between group 2 and group 3. @*Conclusion@#We showed that BM FDG-positive predicted a poorer survival in patients with advanced stage DBLCL. We also found that BMB-negative and BM FDG-positive patients had similar PFS or OS to BMB-positive and BM FDG-negative patients. Further study in a larger population is needed to clarify clinical significance of BM FDG in these patients.

Malignant Transformation of an Epidermoid Cyst in an Intrapancreatic Accessory Spleen: A Case Report / 대한핵의학회잡지

A 33-year-old man was evaluated because of an incidentally found cyst in the pancreatic tail, which was first seen 6 years ago. The cyst was a unilocular cystic mass, 13.0 cm in diameter, and had increased in size in last 2 months. On F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT), the cystic wall showed increased FDG uptake. The patient underwent distal pancreatectomy with suspicion of mucinous cystic neoplasm of the pancreas. The mass turned out to be a squamous carcinoma arising from an epidermoid cyst in an intrapancreatic accessory spleen (ECIPAS). FDG PET/CT may assist recognition of a potential malignant lesion arising from an ECIPAS.

Diagnostic Value of ¹⁸F-FDG PET/CT and MRI in the Preoperative Evaluation of Uterine Carcinosarcoma / 대한핵의학회잡지

PURPOSE@#This study aimed to compare the diagnostic value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and magnetic resonance imaging (MRI) in the preoperative evaluation of uterine carcinosarcoma.@*METHODS@#Fifty-four women with pathologically confirmed uterine carcinosarcoma who underwent preoperative FDG PET/CT and MRI from June 2006 to November 2016 were included. Pathologic findings from primary tumor lesions, para-aortic and pelvic lymph node (LN) areas, and peritoneal seeding lesions were compared with the FDG PET/CT and MRI findings. The maximum standardized uptake value (SUVmax) of the primary tumor and LN was obtained. The tumor-to-liver ratio (TLR) was calculated by dividing the SUVmax of the primary tumor or LN by the mean SUVof the liver.@*RESULTS@#For detecting primary tumor lesions (n = 54), the sensitivity and accuracy of FDGPET/CT (53/54) andMRI (53/54) were 98.2%. The sensitivity, specificity, and accuracy of FDG PET/CT versus MRI were as follows: 63.2% (12/19) versus 26.3% (5/19), 100% (35/35) versus 100% (35/35), and 87.0% versus 74.0%, respectively, for pelvic LN areas (p = 0.016); 85.7% (12/14) versus 42.9%(6/14), 90%(36/40) versus 97.5%(39/40), and 88.9%versus 83.3%, respectively, for para-aortic LN areas (p = 0.004); and 59.4% (19/32) versus 50% (16/32), 100% (22/22) versus 100% (22/22), and 75.9% versus 70.4%, respectively, for peritoneal seeding lesions (p = 0.250). For distant metastasis, the sensitivity, specificity, and accuracy of FDG PET/CTwere 100 (8/8), 97.8 (45/46), and 98.2%, respectively.@*CONCLUSION@#FDG PET/CT showed superior diagnostic accuracy compared to MRI in detecting pelvic and para-aortic LN metastasis in patients with uterine carcinosarcoma. Moreover, FDG PET/CT facilitated the identification of distant metastasis.

Diagnostic Value of ¹⁸F-FDG PET/CT and MRI in the Preoperative Evaluation of Uterine Carcinosarcoma / 대한핵의학회잡지

PURPOSE: This study aimed to compare the diagnostic value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and magnetic resonance imaging (MRI) in the preoperative evaluation of uterine carcinosarcoma.METHODS: Fifty-four women with pathologically confirmed uterine carcinosarcoma who underwent preoperative FDG PET/CT and MRI from June 2006 to November 2016 were included. Pathologic findings from primary tumor lesions, para-aortic and pelvic lymph node (LN) areas, and peritoneal seeding lesions were compared with the FDG PET/CT and MRI findings. The maximum standardized uptake value (SUVmax) of the primary tumor and LN was obtained. The tumor-to-liver ratio (TLR) was calculated by dividing the SUVmax of the primary tumor or LN by the mean SUVof the liver.RESULTS: For detecting primary tumor lesions (n = 54), the sensitivity and accuracy of FDGPET/CT (53/54) andMRI (53/54) were 98.2%. The sensitivity, specificity, and accuracy of FDG PET/CT versus MRI were as follows: 63.2% (12/19) versus 26.3% (5/19), 100% (35/35) versus 100% (35/35), and 87.0% versus 74.0%, respectively, for pelvic LN areas (p = 0.016); 85.7% (12/14) versus 42.9%(6/14), 90%(36/40) versus 97.5%(39/40), and 88.9%versus 83.3%, respectively, for para-aortic LN areas (p = 0.004); and 59.4% (19/32) versus 50% (16/32), 100% (22/22) versus 100% (22/22), and 75.9% versus 70.4%, respectively, for peritoneal seeding lesions (p = 0.250). For distant metastasis, the sensitivity, specificity, and accuracy of FDG PET/CTwere 100 (8/8), 97.8 (45/46), and 98.2%, respectively.CONCLUSION: FDG PET/CT showed superior diagnostic accuracy compared to MRI in detecting pelvic and para-aortic LN metastasis in patients with uterine carcinosarcoma. Moreover, FDG PET/CT facilitated the identification of distant metastasis.

F-18 Fluoride Positron Emission Tomography-Computed Tomography for Detecting Atherosclerotic Plaques

A large number of major cardiovascular events occur in patients due to minimal or some lumen narrowing of the coronary artery. Recent biological studies have shown that the biological composition or vulnerability of the plaque is more critical for plaque rupture compared to the degree of stenosis. To overcome the limitations of anatomical images, molecular imaging techniques have been suggested as promising imaging tools in various fields. F-18 fluorodeoxyglucose (FDG), which is widely used in the field of oncology, is an example of molecular probes used in atherosclerotic plaque evaluation. FDG is a marker of plaque macrophage glucose utilization and inflammation, which is a prominent characteristic of vulnerable plaque. Recently, F-18 fluoride has been used to visualize vulnerable plaque in clinical studies. F-18 fluoride accumulates in regions of active microcalcification, which is normally observed during the early stages of plaque formation. More studies are warranted on the accumulation of F-18 fluoride and plaque formation/vulnerability; however, due to high specific accumulation, low background activity, and easy accessibility, F-18 fluoride is emerging as a promising non-invasive imaging probe to detect vulnerable plaque.

The Clinical Utility of Positron Emission Tomography-computed Tomography in the Evaluation of Inflammatory Bowel Diseases

BACKGROUND/AIMS: Positron emission tomography-computed tomography (PET-CT) is a nuclear imaging technique that provides noninvasive, three dimensional, quantitative images. Recently, PET-CT has been shown to be valuable in assessing patients with inflammatory diseases; however, the clinical utility of PET-CT in the evaluation of inflammatory bowel disease (IBD) has not been defined. Thus, the aim of this study was to determine the clinical utility of PET-CT in the evaluation of IBD. METHODS: Between November 2006 and September 2010, clinical, endoscopic, and radiological data on 14 patients (6 males and 8 females: age range, 33-79 years) with suspected IBD were collected. The standard work-up method for a definite diagnosis of IBD included ileocolonoscopy. RESULTS: The 14 patients were divided into the following five groups: ulcerative colitis (n=4, 29%), intestinal Behcet's disease (n=3, 21%), intestinal tuberculosis (n=2, 14%), malignancy (n=2, 14%), and no abnormal findings with colonoscopy (n=3, 21%). A PET-CT based-diagnosis of IBD correlated with a colonoscopic diagnosis in nine cases (64.3%), but the matching ratio of the distribution of lesions between PET-CT findings and colonoscopic findings was only 18.1% (2/11). CONCLUSIONS: The utility of PET-CT in the diagnosis of IBD requires further evaluation.

Assessment of Viable Myocardium with Nuclear Imaging / 핵의학분자영상

Nuclear cardiac imaging has been widely used to assess viable myocardium in patients with ischemic heart disease. The assessment of viable myocardium is important in selecting patients who will be benefit from revascularization. Although revascularization is indicated in patients with sufficient myocardium, patients with scar tissue should be treated medically. Nuclear imaging methods including myocardial perfusion SPECT and FDG PET have been shown to be effective modalities for identifying viable myocardium.

Added Value of 3D Cardiac SPECT/CTA Fusion Imaging in Patients with Reversible Perfusion Defect on Myocardial Perfusion SPECT / 핵의학분자영상

PURPOSE: Integration of the functional information of myocardial perfusion SPECT (MPS) and the morphoanatomical information of coronary CT angiography (CTA) may provide useful additional diagnostic information of the spatial relationship between perfusion defects and coronary stenosis. We studied to know the added value of three dimensional cardiac SPECT/CTA fusion imaging (fusion image) by comparing between fusion image and MPS. MATERIALS AND METHODS: Forty-eight patients (M:F=26:22, Age: 63.3+/-10.4 years) with a reversible perfusion defect on MPS (adenosine stress/rest SPECT with Tc-99m sestamibi or tetrofosmin) and CTA were included. Fusion images were molded and compared with the findings from the MPS. Invasive coronary angiography served as a reference standard for fusion image and MPS. RESULTS: Total 144 coronary arteries in 48 patients were analyzed; Fusion image yielded the sensitivity, specificity, negative and positive predictive value for the detection of hemodynamically significant stenosis per coronary artery 82.5%, 79.3%, 76.7% and 84.6%, respectively. Respective values for the MPS were 68.8%, 70.7%, 62.1% and 76.4%. And fusion image also could detect more multi-vessel disease. CONCLUSION: Fused three dimensional volume-rendered SPECT/CTA imaging provides intuitive convincing information about hemodynamic relevant lesion and could improved diagnostic accuracy.

Clinical Significance of Myocardial Uptake on F-18 FDG PET/CT Performed in Oncologic Patients / 핵의학분자영상

PURPOSE: F-18 fluorodeoxyglucose (FDG) uptake of myocardium is influenced by various factors. Increased glycolysis, and subsequent increased F-18 FDG uptake has been reported in ischemic cardiomyopathy. However, clinical significance of incidentally found myocardial F-18 FDG uptake has not been clarified. We retrospectively reviewed the degree and pattern of myocardial uptake in patients without history of ischemic heart disease who underwent torso F-18 FDG PET/CT for evaluation of neoplastic disease. MATERIALS AND METHODS: From January 2005 to June 2009, 77 patients who underwent F-18 FDG PET/CT and Tc-99m sestamibi stress/rest SPECT within 3 months were enrolled. RESULTS: Of 77 patients, 55 (71.4%) showed increased F-18 FDG uptake in the myocardium. In this population, 40 showed uniform uptake pattern, while 15 showed focal uptake. In patients with uniform uptake, 17 showed decreased uptake in the septum without perfusion defect on myocardial SPECT. Remaining 23 patients showed uniform uptake, with 1 reversible perfusion defect and 1 fixed perfusion defect. In 15 patients with focal uptake, 9 showed increased F-18 FDG uptake in the base, and only 1 of them showed reversible perfusion defect on myocardial SPECT. In the remaining 6 focal uptake group, 4 had reversible perfusion defect in the corresponding wall, and 1 had apical hypertrophy. CONCLUSION: We demonstrated that septal defect pattern and basal uptake pattern in the myocardium may represent normal variants. Focal myocardial uptake other than normal variants on oncologic torso F-18 FDG PET/CT with routine fasting protocol may suggest ischemic heart disease, thus further evaluation is warranted.

The value of Dedicated Tc-99m MIBI Scintimammography in the Evaluation of Patients with Palpable Breast Lesions in Comparison with Mammography: Preliminary Result / 핵의학분자영상

PURPOSE: There are few studies evaluating the usefulness of dedicated high-resolution scintimammography and no studies using delayed washout with this dedicated high resolution scintimammography for the evaluation of breast lesions. We underwent this study to evaluate the clinical usefulness of Tc-99m MIBI in evaluating patients with palpable breast lesions using dedicated high-resolution scintimammography. MATERIALS AND METHODS: This study included 19 patients with 23 palpable breast lesions who underwent mammography. Tc-99m MIBI was taken to further characterize these lesions. Scintimammography images were acquired with standard craniocaudal and mediolateral oblique views and delayed images were additionally taken. Final conclusions were based on histopathology, either by biopsy or mastectomy results. RESULTS: Eighteen lesions were malignant and five were benign. Mammography was indeterminate for thirteen lesions, nine of those were malignant. Mammography also categorized one lesion as benign in a dense breast, but scintimammography and pathology results showed malignancy. Of the five benign lesions, two were visible on scintimammography, but delayed images showed washout. CONCLUSION: Based on our preliminary results, dedicated high resolution scintimammography seems to be very useful in characterizing palpable lesions that were indeterminate or negative on mammography.

Analysis of Serum Levels of Anti-Mullerian Hormone, Inhibin B, Insulin-Like Growth Factor-I, Insulin-Like Growth Factor Binding Protein-3, and Follicle-Stimulating Hormone with Respect to Age and Menopausal Status

This study was undertaken to investigate age-dependent and postmenopausal changes in the serum levels of anti-Mullerian hormone (AMH), inhibin B, insulin-like growth factor (IGF)-I, IGF-binding protein-3 (IGFBP-3), and follicle-stimulating hormone (FSH), and to determine which of these markers best reflects the aging process in women. A total of 144 women aged 20-59 yr were enrolled in this cross-sectional study. Blood samples were obtained on cycle day 3 of regularly menstruating women (n=111), or at random in postmenopausal women (n=33). Data were analyzed with respect to premenopausal women age groups and compared in pre- and postmenopausal women. Area under the receiver operating characteristic curve (ROCAUC) analyses were performed to assess the ability of each marker to discriminate between the pre- and postmenopausal status. Serum levels of AMH, IGF-I, and IGFBP-3 decreased and serum levels of FSH increased significantly with age in premenopausal women. Serum luteinizing hormone (LH) was higher and inhibin B was lower in women in their 20-30's than in 40's. Serum levels of AMH and IGF-I showed a consistent decrease with all age groups. ROCAUC analysis showed that the diagnostic accuracy of AMH for menopausal status was similar to those of FSH, LH, and inhibin B, and was better than that of IGF-I. In conclusion, the serum AMH level appears to be the best marker of the aging process in premenopausal women.

Patient Preparation and Special Consideration before Radioactive Iodine Therapy / 대한내분비외과학회지

Radioactive iodine therapy is widely used in patients diagnosed with differentiated thyroid cancer. Clinicians have been supplied with several guidelines on how to ablate thyroid tissue or treat thyroid cancer. Here, we review the general procedures involved in patient preparation and special considerations that must be taken before initiating radioactive iodine therapy.

FDG-PET for Evaluating the Antitumor Effect of Intraarterial 3-Bromopyruvate Administration in a Rabbit VX2 Liver Tumor Model

OBJECTIVE: We wanted to investigate the feasibility of using FDG-PET for evaluating the antitumor effect of intraarterial administration of a hexokinase II inhibitor, 3-bromopyruvate (3-BrPA), in a rabbit VX2 liver tumor model. MATERIALS AND METHODS: VX2 carcinoma was grown in the livers of ten rabbits. Two weeks later, liver CT was performed to confirm appropriate tumor growth for the experiment. After tumor volume-matched grouping of the rabbits, transcatheter intraarterial administration of 3-BrPA was performed (1 mM and 5 mM in five animals each, respectively). FDG-PET scan was performed the day before, immediately after and a week after 3-BrPA administration. FDG uptake was semiquantified by measuring the standardized uptake value (SUV). A week after treatment, the experimental animals were sacrificed and the necrosis rates of the tumors were calculated based on the histopathology. RESULTS: The SUV of the VX2 tumors before treatment (3.87+/-1.51[mean+/-SD]) was significantly higher than that of nontumorous liver parenchyma (1.72+/-0.34) (p < 0.0001, Mann-Whitney U test). The SUV was significantly decreased immediately after 3-BrPA administration (2.05+/-1.21) (p = 0.002, Wilcoxon signed rank test). On the one-week follow up PET scan, the FDG uptake remained significantly lower (SUV 1.41+/-0.73) than that before treatment (p = 0.002), although three out of ten animals showed a slightly increasing tendency for the FDG uptake. The tumor necrosis rate ranged from 50.00% to 99.90% (85.48%+/-15.87). There was no significant correlation between the SUV or the SUV decrease rate and the tumor necrosis rate in that range. CONCLUSION: Even though FDG-PET cannot exactly reflect the tumor necrosis rate, FDG-PET is a useful modality for the early assessment of the antitumor effect of intraarterial administration of 3-BrPA in VX2 liver tumor.

Six Months Follow Up Results of "Granulocytes-Colony Stimulating Factor" Based Stem Cell Therapy in Patients with Myocardial Infarction: MAGIC Cell Randomized Controlled Trial

BACKGROUND AND OBJECTIVES: Granulocytes-colony stimulating factor (G-CSF) has a stem cell mobilizing capacity and favorable effects on ventricular remodeling following a myocardial infarction. G-CSF based stem cell therapy has shown favorable results in animal studies. However, the long term outcome of G-CSF based stem cell therapy in clinical trial remains unknown. Herein, we report the six month follow up results of two different G-CSF based stem cell therapy strategies. SUBJECTS AND METHODS: We compared the intra-coronary infusion of mobilized peripheral blood stem cells (PBSCs) with G-CSF (n=10), mobilization with G-CSF alone (n=16) and control percutaneous coronary intervention (PCI) alone (n=15) in patients following a myocardial infarction. RESULTS: At the six month follow up evaluations, the intra-coronary cell infusion was found to have improved the left ventricular (LV) systolic function and remodeling compared to the baseline, whereas G-CSF alone showed no improvement. Therefore, an intra-coronary cell infusion showed better improvements in the LV systolic function (p<0.001) and remodeling (p<0.01) than G-CSF alone. Cell infusion also showed better results than the control PCI alone group, but these did not reach statistical significance with the limited number of patients used in this study. Patients who received G-CSF administration showed a modest increase of binary restenosis (p=0.185) and a greater late loss in the minimal luminal diameter at the 6 month follow up than the control group. CONCLUSION: An intra-coronary cell infusion of mobilized PBSCs using G-CSF was found to be better than G-CSF alone at the six month follow up evaluation. G-CSF was also found to increase the potential risk of restenosis, especially when administered prior to stent implantation. The efficacy of an intra-coronary infusion of mobilized PBSCs should be evaluated in a large randomized controlled trial.

The Usefulness of F-18 FDG PET to Discriminate between Malignant and benign Nodule in Idiopathic Pulmonary Fibrosis / 핵의학분자영상

PURPOSE: Incidence of lung cancer in patients with idiopathic pulmonary fibrosis (IPF) is known to be higher than that in general population. However, it is difficult to discriminate pulmonary nodule in patients with IPF, because underlying IPF can be expressed as lung nodules. We evaluated the diagnostic performance of FDG PET in discriminating lung nodule in patients with IPF. METHODS: We retrospectively reviewed 28 lung nodules in 16 subjects (age; 67.53+/-9.83, M:F=14:2). Two patients had previous history of malignant cancer (small cell lung cancer and subglottic cancer). The diagnostic criteria on chest CT were size, morphology and serial changes of size. FDG PET was visually interpreted, and maximal SUV was calculated for quantitative analysis. RESULTS: From 28 nodules, 18 nodules were interpreted as benign nodules, 10 nodules as malignant nodules by histopahthology or follow-up chest CT. The sensitivity and specificity of FDG PET were 100% and 94.4%, while those of CT were 70.0% and 44.4%, respectively. Malignant nodule was higher maxSUV than that of benign lung nodules (7.68+/-3.96 vs. 1.22+/-0.65, p<0.001). Inflammatory lesion in underlying IPF was significantly lower maxSUV than that of malignant nodules (1.80+/-0.43, p<0.001). The size of malignant and benign nodule were 23.95+/-10.15 mm and 10.83+/-5.23 mm (p<0.01). CONCLUSION: FDG PET showed superior diagnostic performance to chest CT in differentiating lung nodules in patients with underlying IPF. FDG PET could be used to evaluate suspicious malignant lung nodule detected by chest in patients with IPF.