Radioiodine Uptake and Thyroglobulin-Guided Radioiodine Remnant Ablation in Patients with Differentiated Thyroid Cancer: A Prospective, Randomized, Open-Label, Controlled Trial.

BACKGROUND: Radioiodine (131I) remnant ablation (RRA) has become a key step in the postoperative treatment of differentiated thyroid cancer (DTC). However, inadequate or excessive 131I is common using fixed activities. This study was designed to explore the feasibility of radioiodine uptake and thyroglobulin (RAIU-Tg)-guided RRA. METHODS: A total of 277 patients were randomized to the RAIU-Tg-based activity group or a fixed activity of 3.7 GBq group at a ratio of 4:1. The RAIU-Tg-based activity was established based on four levels of RAIU (≤2%, 2-5%, 5-15%, and >15%) and Tg levels (≤2, 2-5, 5-10, and >10 ng/mL). Based on this, 131I activities of 1.1, 1.85, 3.7, and 5.55 GBq were administered. If the levels for RAIU and Tg were not in the same category, the higher activity determined by either RAIU or Tg was administered. Successful RRA was defined as negative diagnostic whole-body scan and Tg <1 ng/mL (anti-Tg antibody negative) or negative diagnostic whole-body scan (anti-Tg antibody positive) under thyrotropin stimulation six months or more post RRA. RESULTS: There was no statistically significant difference in baseline characteristics between the RAIU-Tg-based activity group (n = 207) and the fixed activity group (n = 58). The activity of 131I used in the RAIU-Tg-based activity group (3.26 ± 1.54 GBq) was significantly lower than that used in the fixed activity group (p < 0.0001), whereas the rate of successful RRA in the RAIU-Tg-based activity group was significantly higher than the rate in the fixed activity group (94.2% vs. 70.7%; p < 0.0001). The rates of successful RRA in the four subgroups of the RAIU-Tg-based activity group were comparable (p = 0.543). Although there was no statistically significant difference in the incidence of total/short-term adverse effects between the RAIU-Tg-based activity group and the fixed activity group, a significantly lower incidence of intermediate adverse effects, which predominantly consisted of xerostomia, was reported in the RAIU-Tg-based activity group. CONCLUSIONS: Compared to a fixed activity of 3.7 GBq, RAIU-Tg-guided dosimetry can improve the success rate and decrease the incidence of intermediate side effects of RRA in postoperative patients with DTC.

Predicting 131I-avidity of metastases from differentiated thyroid cancer using 18F-FDG PET/CT in postoperative patients with elevated thyroglobulin.

The quantitative relationship between iodine and glucose metabolism in metastases from differentiated thyroid cancer (DTC) remains unknown. Aim of the prospective study was to establish the value of 18F-FDG PET/CT in predicting 131I-avidity of metastases from DTC before the first radioiodine therapy. A total of 121 postoperative DTC patients with elevated stimulated serum thyroglobulin (ssTg) who underwent 131I adjuvant therapy or therapy after 18F-FDG PET/CT scan were enrolled. The Receiver operating characteristic curve was established to create an optimal cut-off point and evaluate the value of SUVmax for predicting 131I-avidity. In our study, the median SUVmax in 131I-nonavid metastatic target lesions was also significantly higher than that in 131I-avid metastatic target lesions (5.37 vs. 3.30; P = 0.000). At a cut-off value of 4.0 in SUVmax, the area under curve was 0.62 with the sensitivity, specificity, positive predictive value and negative predictive value of 75.3%, 56.7%, 76.1%, and 54.8%, respectively. These results suggest that 18F-FDG PET/CT may be of great value in identifying metastases in postoperative DTC patients with elevated ssTg before 131I administration, leading to an improved management of disease. 18F-FDG positive metastatic DTC with SUVmax of greater than 4.0 possesses higher probability of non-avidity to radioiodine.

Clinical Evaluation of the Immune Colloidal Gold Method for Rapid Qualitative and Quantitative Measurement of Thyroid-Stimulating Hormone as an Assay for Hypothyroidism.

INTRODUCTION: The immune colloidal gold (ICG) method of measuring thyroid-stimulating hormone (TSH) is a rapid and easy-to-perform test, allowing off-site measurements. This study compared the clinical utility of the first ICG-based qualitative and quantitative TSH test methods in China with the third-generation serum TSH assay used worldwide. METHODS: Fingertip and venous blood was collected within 30 min from 283 patients initially suspected of hypothyroidism. TSH was measured in fingertip blood using ICG-based qualitative quantitative tests. Serum TSH in venous blood was tested using the third-generation serum TSH assay. Correlations between systems were tested by kappa or Spearman correlation coefficients. RESULTS: Compared with the third-generation serum TSH assay, the ICG-qualitative TSH test kit had a kappa coefficient of 0.86, a sensitivity of 85.00%, and a specificity of 99.38% in screening for hypothyroidism. The percentages of false negatives and false positives among all subjects were 6.38% and 0.35% respectively; the total consistency rate of the two methods was 93.26%. When compared with the third-generation serum TSH assay, the ICG-quantitative TSH analysis system had a Spearman correlation coefficient of 0.91, a sensitivity of 88.43%, and a specificity of 98.77%. The percentages of false negatives and false positives among all subjects were 4.95% and 0.71%, respectively; the total consistency rate of the two methods was 94.35%. CONCLUSION: Both ICG-based assays are easier and faster to perform than the third-generation, laboratory-based serum TSH assay method. The ICG-based methods showed acceptable performance in the simplified screening for hypothyroidism. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT01921452. FUNDING: Merck Serono Co., Ltd.

Graphene-based electromagnetically induced transparency with coupling Fabry-Perot resonators.

We investigate the plasmonic analog of electromagnetically induced transparency (EIT) using two adjacent graphene-based Fabry-Perot (F-P) resonators side coupling to a nanoribbon waveguide. By the coupling mode theory in time and F-P resonant model, the destructive interference from the coupling of the two F-P resonators results in the EIT-like optical response. The induced peak and width of the transparency window can be dynamically manipulated by varying the coupling distance of the two resonators, and the transparent window is easily shifted by tuning the resonator length or the chemical potential of the graphene nanoribbon. In order to verify the characteristics of slow light, the group index profile is analyzed at different coupling distances. The proposed graphene-based EIT-like system could open up new opportunities for potential applications in plasmonic slow light and optical information buffering devices.

Plasmonic bandpass filter based on graphene nanoribbon.

A plasmonic bandpass filter based on graphene is proposed and numerically investigated using the finite-difference time-domain method. The proposed filter has a very simple structure, including two graphene nanoribbon waveguides laterally coupled to a graphene ribbon resonator. The transmission efficiency can be tuned by altering the coupling distance between the ribbons. At the same time, the variation of the transmission spectra is investigated by tuning the size of the graphene resonant ribbon. Notably, due to the unique electronic tunability of graphene, the transmission spectra can be freely tuned in a broad frequency range by choosing the chemical potential, which exhibits more flexible tunability than that used in conventional metallic devices. Attributed to the standing wave distribution of different modes excited in the graphene resonant ribbon, the proposed filter can be used for the plasmonic device with the capability of band selection or power splitting by locating the output waveguide ports in the suitable positions.

A first described chest wall metastasis from colon cancer demonstrated with (18)F-FDG PET/CT.

It is well known that, haematogenous colon cancer metastases are most commonly found in the liver, less likely in the lungs through the paravertebral venous system and rarely in other organs. Sporadic clinical cases of colon cancer metastases to the abdominal wall, the thyroid or the adrenal glands have been reported. Here, we present an uncommon case of chest wall metastasis from colon cancer demonstrated with 2-fluoro [fluorine-18]-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT). A 52 years old female patient was examined after she felt a swelling mass above her left breast. Tumor makers, such as serum cancer embryonic antigen (CEA) 146.22kU/L (normal range:0.00~37.0kU/L) and CA19-9 (258.16µg/L (normal range:0.00~10.0µg/L) and neuron-specific enolase (NSE) 78.2 (normal range: 0.00~17.00) were abnormally high. Chest CT revealed the soft tissue density mass on the left anterior chest wall with invasion of left 4th rib, and CT-guided biopsy showed a poorly differentiated adenocarcinoma of unkown origin. The patient was then referred for the (18)F-FDG-PET scan which was performed one hour after the intravenous injection of 370MBq of (18)F-FDG (Discovery Camera, VCT, GE, USA) and showed in addition to the chest mass, abnormal (18)F-FDG accumulation in both lungs, left supraclavicular and peritoneal lymph nodes. Furthermore, high (18)F-FDG uptake was detected in the sigmoid. Pathology findings from colonoscopy confirmed that this was a sigmoid colon adenocarcinoma. So far, chest wall metastasis from colon cancer as an initial finding has not been reported. Usually, an initial chest wall mass is hardly suspected to be a colon cancer metastasis. Abnormal serum tumor markers such as CEA and CA19-9 supported the diagnosis of a gastrointestinal adenocarcinoma. In our case, we found high serum NSE and normal findings of bowel wall on the CT scan, thus without the positive (18)F-FDG findings, one would probably consider as first diagnosis: chest wall metastasis from lung cancer, or a neuroendocrine tumor. The unusual finding in this case was that on the CT images there was no obvious local density of the intestine, no bowel wall thickening, or suspicious nodular lesions. Segmental (18)F-FDG accumulation seen in the sigmoid colon had early maximum standardized uptake value (SUV(max)) 7.3 and in 1h delayed estimation, 8.1. Colonoscopy showed that the (18)F-FDG-avid area at the colon was circular and thickened. "Hot" lesions found in both lungs, the supraclavicular and retroperitoneal lymph nodes by (18)F-FDG PET/CT scan were considered to be most probably metastases from colon adenocarcinoma. In conclusion, PET as a rather simple procedure and less dependent on bowel preparation diagnosed the primary colon cancer, its metastases and specifically a first described chest wall metastasis, while CT alone did not show the primary tumor.

Predictive value of osteocalcin in bone metastatic differentiated thyroid carcinoma.

OBJECTIVES: To evaluate the diagnostic value of serum osteocalcin in the detection of bone metastases from differentiated thyroid carcinoma (DTC). DESIGN AND METHODS: Serum samples from DTC patients with (DTC BM+, n=19) or without bone metastases (DTC BM-, n=19), and matched healthy volunteers (n=30) were tested for serum osteocalcin with electrochemiluminescent immunoassay. RESULTS: Osteocalcin was higher in DTC BM+ than in DTC BM- patients (+35.8%, p=0.002), acting as an independent risk factor for bone metastases (R(2)=0.142, p=0.039). The sensitivity was 78.9% and the specificity was 63.2% at a cut-off value of 11.2 microg/L. CONCLUSIONS: Serial measurements of osteocalcin could be useful in the detection of bone metastases from DTC.