PURPOSE: Thyroid cancer is the most common endocrine cancer and its incidence has continuously increased in the last three decades all over the world. We aimed to evaluate the prognostic value of extranodal extension (ENE) of thyroid cancer. MATERIALS AND METHODS: We performed a systematic search of MEDLINE (from inception to June 2014) and EMBASE (from inception to June 2014) for English-language publication. The inclusion criteria were studies of thyroid cancer that reported the prognostic value of ENE in thyroid cancer. Reviews, abstracts, and editorial materials were excluded, and duplicate data were removed. Two authors performed the data extraction independently. RESULTS: 6 studies including 1830 patients were eligible for inclusion in the study. All patients included in the meta-analysis had papillary thyroid cancer (PTC). Recurrence-free survival was analyzed based on 3 studies. The pooled hazard ratio for recurrence was 2.01 [95% confidence interval (CI) 1.19–3.40, p=0.009]. Disease-specific survival was analyzed based on 3 studies with 973 patients. Patients of PTC with ENE showed 3.37-fold higher risk of death from the disease (95% CI 1.55–7.32, p=0.002). CONCLUSION: ENE should be considered to be a poor prognostic marker in thyroid cancer; such knowledge might improve the management of individual patients. This might facilitate the planning of appropriate ablation therapy and tailored patient follow-up from the beginning of treatment.
Endocrine Gland Neoplasms ; Follow-Up Studies ; Humans ; Incidence ; Lymph Nodes ; Prognosis ; Publications ; Recurrence ; Thyroid Gland* ; Thyroid Neoplasms*

OBJECTIVE: Concurrent low brain and high liver uptake are sometimes observed on fluorine-18-labeled fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET). We investigated the potential clinical significance of this uptake pattern related to metabolic syndrome (MS). MATERIALS AND METHODS: We retrospectively reviewed data from 264 consecutive males who had undergone general health check-ups, including FDG PET/CT scans. After an overnight fast, the men had their peripheral blood drawn and the levels of various laboratory parameters measured; an FDG PET/CT scan was performed on the same day. We measured the maximum standardized uptake values of the brain and liver from regions of interest manually placed over the frontal cortex at the level of the centrum semiovale and the right lobe of the liver parenchyma, respectively. RESULTS: Fasting blood glucose (FBG; odds ratio [OR] = 1.063, p < 0.001) and glycated hemoglobin (HbA1c; OR = 3.634, p = 0.010) were the strongest predictive factors for low brain FDG uptake, whereas waist circumference (OR = 1.200, p < 0.001) and γ-glutamyl transpeptidase (OR = 1.012, p = 0.001) were the strongest predictive factors for high liver uptake. Eleven subjects (4.2%) showed concurrent low brain and high liver FDG uptake, and all but one of these subjects (90.9%) had MS. Systolic blood pressure, waist circumference, FBG, triglyceride, alanine aminotransferase, insulin resistance (measured by homeostasis model assessment), insulin, HbA1c, and body mass index were higher in subjects with this FDG uptake pattern than in those without (all, p < 0.001). CONCLUSION: Concurrent low brain and high liver FDG uptake were closely associated with MS. Moreover, subjects with this pattern had higher values for various cardiovascular risk factors than did those without.
Alanine Transaminase ; Blood Glucose ; Blood Pressure ; Body Mass Index ; Brain* ; Fasting ; Frontal Lobe ; Hemoglobin A, Glycosylated ; Homeostasis ; Humans ; Insulin ; Insulin Resistance ; Liver* ; Male ; Odds Ratio ; Positron-Emission Tomography ; Positron-Emission Tomography and Computed Tomography ; Retrospective Studies ; Risk Factors* ; Triglycerides ; Waist Circumference

Positron emission tomography (PET) has come to the practice of oncology. It is known that 18F-fluorodeoxyglucose (FDG) PET is more sensitive for the assessment of treatment response than conventional imaging. In addition, PET has an advantage in the use of quantitative analysis of the study. Nowadays, various PET parameters are adopted in clinical settings. In addition, a wide range of factors has been known to be associated with FDG uptake. Therefore, there has been a need for standardization and harmonization of protocols and PET parameters. We will introduce PET parameters and discuss major issues in this review.
Image Processing, Computer-Assisted ; Medical Oncology ; Positron-Emission Tomography ; Radiopharmaceuticals

Obesity, an increasingly common problem in modern societies, results from energy intake chronically exceeding energy expenditure. This imbalance of energy can be triggered by the internal state of the caloric equation (homeostasis) and non-homeostatic factors, such as social, cultural, psychological, environmental factors or food itself. Nowadays, positron emission tomography (PET) radiopharmaceuticals have been examined to understand the cerebral control of food intake in humans. Using ¹⁵O–H₂ PET, changes in regional cerebral blood flow (rCBF) coupled to neuronal activity were reported in states of fasting, satiation after feeding, and sensory stimulation. In addition, rCBF in obese subjects showed a greater increase in insula, the primary gustatory cortex. ¹⁸F–fluorodeoxyglucose PET showed higher metabolic activity in postcentral gyrus of the parietal cortex and lower in prefrontal cortex and anterior cingulate cortex in obese subjects. In addition, dopamine receptor (DR) PET demonstrated lower DR availability in obese subjects, which might lead to overeating to compensate. Brain PET has been utilized to reveal the connectivity between obesity and brain. This could improve understanding of obesity and help develop a new treatment for obesity.
Brain ; Cerebrovascular Circulation ; Eating ; Electrons ; Energy Intake ; Energy Metabolism ; Fasting ; Gyrus Cinguli ; Humans ; Hyperphagia ; Neurons ; Obesity ; Parietal Lobe ; Positron-Emission Tomography ; Prefrontal Cortex ; Radiopharmaceuticals ; Receptors, Dopamine ; Satiation ; Somatosensory Cortex

Obesity, an increasingly common problem in modern societies, results from energy intake chronically exceeding energy expenditure. This imbalance of energy can be triggered by the internal state of the caloric equation (homeostasis) and non-homeostatic factors, such as social, cultural, psychological, environmental factors or food itself. Nowadays, positron emission tomography (PET) radiopharmaceuticals have been examined to understand the cerebral control of food intake in humans. Using ¹⁵O–H₂ PET, changes in regional cerebral blood flow (rCBF) coupled to neuronal activity were reported in states of fasting, satiation after feeding, and sensory stimulation. In addition, rCBF in obese subjects showed a greater increase in insula, the primary gustatory cortex. ¹⁸F–fluorodeoxyglucose PET showed higher metabolic activity in postcentral gyrus of the parietal cortex and lower in prefrontal cortex and anterior cingulate cortex in obese subjects. In addition, dopamine receptor (DR) PET demonstrated lower DR availability in obese subjects, which might lead to overeating to compensate. Brain PET has been utilized to reveal the connectivity between obesity and brain. This could improve understanding of obesity and help develop a new treatment for obesity.

Background: Postsurgical hypocalcemia is the most common and troublesome consequence of thyroidectomy. We investigated the potential role of routine calcium or vitamin D supplementation in preventing postsurgical hypocalcemia. Methods: We searched MEDLINE and Embase for English-language publications using the keywords “calcium,” “vitamin D,” and “thyroid cancer.” The primary outcome was any postoperative hypocalcemia, and the secondary outcome was symptomatic hypocalcemia. Results: Four studies that included 381 patients were eligible for this meta-analysis. A random-effects model showed no significant difference in the occurrence of hypocalcemia between calcium/vitamin D treatment and placeboo treatment. However, the occurrence of symptomatic hypocalcemia was lower in patients with calcium/vitamin D treatment. In the combined results, preoperative calcium and vitamin D supplementation were associated with a reduced incidence of symptomatic hypocalcemia. Conclusions Our findings support the use of preoperative calcium and vitamin D supplementation in conjunction with routine postsurgical supplementation for patients after total thyroidectomy.

Background: The aim of this study was to develop a scoring system to stratify the risk of papillary thyroid cancer (PTC) and to select the proper management. Methods: We performed a systematic search of MEDLINE and Embase. Data regarding patients’ prognoses were obtained from the included studies. Odds ratios (ORs) with statistical significance were extracted from the publications. To generate a risk scoring system (RSS), ORs were summed (RSS1), and summed after natural-logarithmic transformation (RSS2). RSS1 and RSS2 were compared to the eighth edition of the American Joint Committee on Cancer (AJCC) staging system and the 2015 American Thyroid Association (ATA) guidelines for thyroid nodules and differentiated thyroid carcinoma. Results: Five meta-analyses were eligible for inclusion in the study. Eight variables (sex, tumour size, extrathyroidal extension, BRAF mutation, TERT mutation, histologic subtype, lymph node metastasis, and distant metastasis) were included. RSS1 was the best of the analysed models. Conclusion We developed and validated a new RSS derived from previous meta-analyses for patients with PTC. This RSS seems to be superior to previously published systems.

We evaluated the efficacy of recombinant human thyroid-stimulating hormone (rhTSH) versus thyroid hormone withdrawal (THW) prior to radioiodine remnant ablation (RRA) in thyroid cancer. A systematic search of MEDLINE, EMBASE, the Cochrane Library, and SCOPUS was performed. Randomized controlled trials that compared ablation success between rhTSH and THW at 6 to 12 months following RRA were included in this study. Six trials with a total of 1,660 patients were included. When ablation success was defined as a thyroglobulin (Tg) cutoff of 1 ng/mL (risk ratio, 0.99; 95% confidence interval, 0.96-1.03) or a Tg cutoff of 1 ng/mL plus imaging modality (RR 0.97; 0.90-1.05), the results of rhTSH and THW were similar. There were no significant differences when ablation success was defined as a Tg cutoff of 2 ng/mL (RR 1.03; 0.95-1.11) or a Tg cutoff of 2 ng/mL plus imaging modality (RR 1.02; 0.95-1.09). When a negative 131I-whole body scan was used solely as the definition of ablation success, the effects of rhTSH and THW were not significantly different (RR 0.97; 0.93-1.02). Therefore, ablation success rates are comparable when RRA is prepared by either rhTSH or THW.
Catheter Ablation ; Clinical Trials as Topic ; Databases, Factual ; Humans ; Iodine Radioisotopes/*therapeutic use ; Radiopharmaceuticals/*therapeutic use ; Recombinant Proteins/biosynthesis/genetics/therapeutic use ; Risk ; Thyroglobulin/analysis/metabolism ; Thyroid Neoplasms/*drug therapy/ultrasonography ; Thyrotropin/genetics/metabolism/*therapeutic use ; Treatment Outcome ; Whole Body Imaging

OBJECTIVES: Previously published studies showed that the standard tumor-to-blood standardized uptake value (SUV) ratio (SUR) was a more accurate prognostic method than tumor maximum standardized uptake value (SUV(max)). This study evaluated and compared prognostic value of positron emission tomography (PET) parameters and normalized value of PET parameters by blood pool SUV in non-small-cell lung cancer (NSCLC) patients who received curative surgery.METHODS: Seventy-seven patients who underwent curative resection for NSCLC between January 2010 to December 2013 were enrolled in this study. ¹⁸Fluorine-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) was performed before surgery. The mean standardized uptake value (SUV(mean)), SUV(max), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of each lesion was measured, on the workstation. SUR(mean), SUR(max), and TLGSUR were calculated by dividing each of them by descending aorta SUV(mean). Cox proportional hazards regression was used to analyze the effect of age, sex, pathological parameters, and PET parameters on recurrence and death.RESULTS: In Cox regression analysis, N stage predicted for both recurrence (p < 0.0001) and death (p < 0.0001). SUR(max) predicted recurrence (p = 0.0014), not death. Area under the receiver operating characteristic curve of SUR(max) was 0.759 with cutoff value 4.004. However, SUV(max), SUV(mean), MTV, TLG, SUR(mean), and TLGSUR predicted neither recurrence nor death.CONCLUSIONS: Among PET parameters, SUR(max) was the independent predictor of recurrence in NSCLC patients who received curative surgery. N stage was the independent prognostic factor for both recurrence and death. Both parameters could be used to stratify the risk of NSCLC patients.
Aorta, Thoracic ; Electrons ; Fluorodeoxyglucose F18 ; Glycolysis ; Humans ; Lung Neoplasms ; Lung ; Methods ; Positron-Emission Tomography ; Prognosis ; Recurrence ; ROC Curve ; Tumor Burden