Visualizing Hand Force with Wearable Muscle Sensing for Enhanced Mixed Reality Remote Collaboration.

In this paper, we present a prototype system for sharing a user's hand force in mixed reality (MR) remote collaboration on physical tasks, where hand force is estimated using wearable surface electromyography (sEMG) sensor. In a remote collaboration between a worker and an expert, hand activity plays a crucial role. However, the force exerted by the worker's hand has not been extensively investigated. Our sEMG-based system reliably captures the worker's hand force during physical tasks and conveys this information to the expert through hand force visualization, overlaid on the worker's view or on the worker's avatar. A user study was conducted to evaluate the impact of visualizing a worker's hand force on collaboration, employing three distinct visualization methods across two view modes. Our findings demonstrate that sensing and sharing hand force in MR remote collaboration improves the expert's awareness of the worker's task, significantly enhances the expert's perception of the collaborator's hand force and the weight of the interacting object, and promotes a heightened sense of social presence for the expert. Based on the findings, we provide design implications for future mixed reality remote collaboration systems that incorporate hand force sensing and visualization.

Improved conductivity of flower-like MnWO4 on defect engineered graphitic carbon nitride as an efficient electrocatalyst for ultrasensitive sensing of chloramphenicol.

Environmental hazards caused by chloramphenicol has attained special attention. Fast, accurate and reliable detection of chloramphenicol in foodstuffs and water samples is of utmost importance. Herein, we developed a g-C3N4/MnWO4 composite for the selective and sensitive detection of chloramphenicol. Successful fabrication of g-C3N4/MnWO4 composite was verified by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), x-ray diffraction (XRD) and x-ray photo electron spectroscopy (XPS) techniques. Electrochemical characteristics were evaluated by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The g-C3N4/MnWO4 modified glassy carbon electrode has shown the highest electrocatalytic activity towards chloramphenicol with a decreased reduction potential of -0.547 V and increased cathodic peak current. The developed sensor has shown excellent performance for the detection of chloramphenicol with a sensitivity of 0.9986 µA nM-1 cm-2 and LOD of 1.03 nM in a broad linear range of 4.0-71 nM. In addition, the fabricated sensor has achieved anti-interference ability, good stability, excellent repeatability and remarkable reproducibility for the detection of chloramphenicol. The fabricated sensor applied for the determination of chloramphenicol in milk, human blood serum and sewage samples, in which significant and satisfactory results were achieved.

Correlations of the Gastric and Duodenal Microbiota with Histological, Endoscopic, and Symptomatic Gastritis.

Mucosal inflammation is characterized by neutrophil and mononuclear cell infiltration. This study aimed to determine the gastric and duodenal microbiota associated with histological, endoscopic, and symptomatic gastritis. Dyspeptic adults who presented for evaluation were included. Subjects with either comorbidities or recent drug intake were excluded. Three endoscopic biopsies were obtained from the antrum, body, and duodenum. Next-generation sequencing for 16S ribosomal RNA V1⁻V2 hypervariable regions was performed. The correlation between the composition of microbiota and the degree of inflammatory cell infiltration, endoscopic findings, and Patient Assessment of Gastrointestinal Disorders Symptom Severity Index (PAGI-SYM) score was analyzed. In 98 included subjects, microbial communities in the antrum and body showed Bray⁻Curtis similarity; however, those in the duodenum showed dissimilarity. Histological and endoscopic gastritis was associated with the abundance of Helicobacter pylori and that of commensal bacteria in the stomach. The abundances of Variovorax paradoxus and Porphyromonas gingivalis were correlated with histological gastritis, but not with endoscopic or symptomatic gastritis. The total PAGI-SYM score showed a stronger correlation with the duodenal microbiota (Prevotella nanceiensis and Alloprevotella rava) than with the gastric microbiota (H. pylori, Neisseria elongate, and Corynebacterium segmentosum). Different correlations of the gastric and duodenal microbiota with histological, endoscopic, and symptomatic gastritis were observed for the first time at the species level. H. pylori-negative gastritis is not associated with endoscopic or symptomatic gastritis. Only H. pylori-induced endoscopic gastritis requires gastric cancer surveillance. Owing to the weak correlation with H. pylori, symptomatic gastritis should be assessed separately from histological and endoscopic gastritis.

Effects of corn particle size on nutrient utilization in pigs evaluated under optimal and heat stress conditions.

The effects of corn particle size on nutrient digestibility and energy utilization in pigs were determined under optimal (experiment 1, 25 ± 1 °C) or heat stress (experiment 2, 37 ± 1 °C) conditions. In Exp. 1 and 2, five experimental diets were tested using a 5 × 5 Latin square design involving five barrows (Landrace × Yorkshire × Duroc, average initial body weight of 30 ± 1 kg and 45.0 ± 1.8 kg, respectively, in individual metabolic cages). Dietary treatments were as follows: 200-, 300-, 400-, 600-, 800-µm corn particle sizes obtained by mesh screens. Under optimal thermal conditions, digestibility of dry matter (DM) and crude fiber (CF) from 200-µm diet was higher (P < 0.05) compared to that from the 300-µm and 400-µm diets. The digestibility of crude protein (CP) and ether extract (EE) was the highest (P < 0.05) at the 200-µm particle size. The apparent total tract digestibility of energy was significantly higher (P < 0.05) on the 200-µm diet. Under heat stress, digestibility of CF when corn was ground to 600 µm was higher (P < 0.05) compared to 300 and 400 µm. Digestibility of NDF and ADF was the highest (P < 0.05) at 600-µm corn particle size. In conclusion, grinding corn to 200-µm corn particles had a positive effect on DM, CP, EE, and CF under optimal thermal condition, while the 600-µm corn particle size had positive effects on digestibility of CF, NDF, and ADF than 200-µm corn particle size under heat stress.

Efficacy and safety of electromagnetic acupuncture using an electromagnetic therapy stimulator (Whata153) for the treatment of chronic low back pain: Study protocol for a single-center, parallel-arm, randomized clinical trial.

BACKGROUND: Chronic low back pain is one of the major conditions causing serious personal and social difficulties in modern society. There are several noninvasive therapies for chronic low back pain; however, the effects of electromagnetic acupuncture have not been studied. Here, we describe the protocol for a study that will investigate the efficacy and safety of electromagnetic acupuncture for patients with chronic low back pain. METHODS: The study has been designed as a double-blind, single-center, parallel-arm, sham-controlled, randomized clinical trial. A total of 104 patients with chronic low back pain who meet the criteria for selection and exclusion will be enrolled in a 1:1 ratio in an electromagnetic acupuncture group or a sham group. Sterilized disposable needles will be inserted at 6 acupoints, following which stimulation via an electromagnetic (Whata153) or a placebo (sham) stimulator will be applied. The 2 groups will receive a total of 6 treatment sessions over 3 weeks, with 1 follow-up visit within 3 days after the final treatment. The primary outcome will be the change in the visual analog scale (VAS) score for pain from baseline (visit 1, first treatment session) to the follow-up visit (visit 7, after treatment completion). The secondary outcomes will be as follows: changes in the VAS score for pain from baseline (visit 1) to visits 3 (third session) and 5 (fifth session); changes in the VAS score for pain at all assessment points from baseline (visit 1) to the follow-up visit (visit 7); changes in the Oswestry Disability Index (ODI) from visit 1 to visits 3, 5, and 7; and the change in ODI at all assessment points from visit 1 to visit 7. DISCUSSION: The results of this trial are expected to provide important clinical information on the efficacy and safety of electromagnetic acupuncture for patients with chronic low back pain.

Prevalence of BRAFV600E Mutation in Follicular Variant of Papillary Thyroid Carcinoma and Non-Invasive Follicular Tumor with Papillary-Like Nuclear Features (NIFTP) in a BRAFV600E Prevalent Area.

BACKGROUND: BRAFV600E mutation status and prevalence of non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) has not yet been reported in Korea. The aim of this study was to investigate the significance of the BRAFV600E mutation in the follicular variant of papillary thyroid carcinoma (FVPTC) and to determine the prevalence of NIFTP in BRAFV600E mutation-prevalent Korean patients. METHODS: This study retrospectively analyzed 1,417 consecutive patients who underwent total thyroidectomy with routine prophylactic central lymph node dissection for papillary thyroid carcinoma (PTC). BRAFV600E mutation analysis was performed routinely using multiplex polymerase chain reaction by applying dual priming oligonucleotide. Clinicopathological characteristics and ultrasonographic findings were compared between BRAFV600E mutation-positive and -negative groups for FVPTC. Pathologists reviewed the pathology slides according to consensus diagnostic criteria for the encapsulated FVPTC and NIFTP. RESULTS: The prevalence of the BRAFV600E mutation in all subtypes of PTC was 61.0% (861/1,411). FVPTC presented a BRAFV600E mutation rate of 27.3%. The FVPTC patients with BRAFV600E mutation were older than those with no BRAFV600E mutation (P = 0.021). The prevalence of NIFTP was 0.18% among all PTC patients (2/1,411) and the proportion of NIFTP among FVPTC was 9.1% (2/22). CONCLUSION: The BRAFV600E mutation is prevalent in Korean patients with FVPTC in a region with high frequency of the BRAFV600E mutation and very low prevalence of NIFTP compared with that reported in western studies.

Addition of nonalbumin proteinuria to albuminuria improves prediction of type 2 diabetic nephropathy progression.

BACKGROUND: Albuminuria is generally accepted as a sensitive marker of diabetic nephropathy but has limitations in predicting its progression. The aim of this study was to evaluate the use of nonalbumin proteinuria in addition to albuminuria for predicting the progression of type 2 diabetic nephropathy. METHODS: In this retrospective observational study, the urine albumin-to-creatinine ratio (ACR) and the nonalbumin protein-to-creatinine ratio (NAPCR) were measured in 325 patients with type 2 diabetes and estimated glomerular filtration rates (eGFR) ≥30 mL/min/1.73 m2. The patients were divided into four groups based on the cutoff points for the urinary ACR (30 mg/g) and NAPCR (120 mg/g). The renal outcomes were chronic kidney disease (CKD) progression and accelerated eGFR decline. RESULTS: During the 4.3-year follow-up period, 25 (7.7%) patients showed CKD progression and 69 (21.2%) patients showed accelerated eGFR decline. After adjusting for nine clinical parameters, the group with a NAPCR greater than 120 mg/g exhibited higher cumulative incidences of CKD progression (hazard ratio 6.84; P = 0.001) and accelerated eGFR decline (hazard ratio 1.95; P = 0.011) than the group with a NAPCR < 120 mg/g. In patients with normoalbuminuria, the group with NAPCR levels greater than 120 mg/g also exhibited a higher cumulative incidence than that with NAPCR levels <120 mg/g of CKD progression (hazard ratio 21.82; P = 0.005). The addition of NAPCR to ACR improved the model fit for CKD progression and accelerated eGFR decline. CONCLUSION: Nonalbumin proteinuria showed additional value over and above that of albuminuria for predicting the progression of CKD in patients with type 2 diabetes.

Comparison Between Real-Time PCR and Pyrosequencing for Detection of BRAF V600E Mutation in Thyroid Fine-Needle Aspirates.

The BRAF V600E mutation test has proven diagnostic value in thyroid fine-needle aspiration. The real-time polymerase chain reaction (RT-PCR) has recently been introduced as a new method for BRAF mutation detection. We performed BRAF V600E detection in 126 cases of thyroid fine-needle aspiration, using RT-PCR and pyrosequencing. BRAF V600E mutation was detected in 78 (61.9%) of 126 cases by RT-PCR and in 74 (57.8%) by pyrosequencing. Of the 98 papillary thyroid carcinoma samples, the BRAF V600E mutation was identified in 72 by RT-PCR and in 70 by pyrosequencing (sensitivities of 71.6% and 71.4%, respectively). Among 28 benign nodules, 6 false-positive cases were detected by RT-PCR, whereas 4 false-positive cases were detected by pyrosequencing (specificities of 78.6% and 85.7%, respectively). When analyzing 104 cases after excluding equivocal samples, pyrosequencing had a marginally higher specificity than RT-PCR (100% vs. 78.3%, P=0.074). After modifying the cut-off criteria, the low RT-PCR specificity improved to a similar or a slightly lower specificity compared with that of pyrosequencing. In the titration assay mixing the mutant DNA with the wild-type DNA in varying proportions, RT-PCR was sensitive enough to detect the mutation in a mixture containing 0.001% mutant DNA, whereas the limit of detection was 10% for pyrosequencing. In conclusion, compared with pyrosequencing, RT-PCR was more sensitive, faster, and more convenient, but less specific, for detecting the BRAF V600E mutation. A readjustment or modification of the interpretation criteria may be necessary to reduce false-positive RT-PCR results and improve the specificity while maintaining the sensitivity.

Detection of EGFR and KRAS Mutation by Pyrosequencing Analysis in Cytologic Samples of Non-Small Cell Lung Cancer.

EGFR and KRAS mutations are two of the most common mutations that are present in lung cancer. Screening and detecting these mutations are of issue these days, and many different methods and tissue samples are currently used to effectively detect these two mutations. In this study, we aimed to evaluate the testing for EGFR and KRAS mutations by pyrosequencing method, and compared the yield of cytology versus histology specimens in a consecutive series of patients with lung cancer. We retrospectively reviewed EGFR and KRAS mutation results of 399 (patients with EGFR mutation test) and 323 patients (patients with KRAS mutation test) diagnosed with lung cancer in Konkuk University Medical Center from 2008 to 2014. Among them, 60 patients had received both EGFR and KRAS mutation studies. We compared the detection rate of EGFR and KRAS tests in cytology, biopsy, and resection specimens. EGFR and KRAS mutations were detected in 29.8% and 8.7% of total patients, and the positive mutation results of EGFR and KRAS were mutually exclusive. The detection rate of EGFR mutation in cytology was higher than non-cytology (biopsy or resection) materials (cytology: 48.5%, non-cytology: 26.1%), and the detection rate of KRAS mutation in cytology specimens was comparable to non-cytology specimens (cytology: 8.3%, non-cytology: 8.7%). We suggest that cytology specimens are good alternatives that can readily substitute tissue samples for testing both EGFR and KRAS mutations. Moreover, pyrosequencing method is highly sensitive in detecting EGFR and KRAS mutations in lung cancer patients.

Comparison of Analytical and Clinical Performance of HPV 9G DNA Chip, PANArray HPV Genotyping Chip, and Hybrid-Capture II Assay in Cervicovaginal Swabs.

BACKGROUND: Human papillomavirus (HPV) infection can be detected by using several molecular methods, including Hybrid-Capture II (HC2) assay and variable HPV DNA chip tests, although each method has different sensitivities and specificities. METHODS: We performed HPV 9G DNA Chip (9G) and PANArray HPV Genotyping Chip (PANArray) tests on 118 cervicovaginal swabs and compared the results with HC2, cytology, histology, and direct sequencing results. RESULTS: The overall and high-risk HPV (HR-HPV) positivity rates were 62.7% and 44.9% using 9G, and 61.0% and 30.5% using PANArray, respectively. The positivity rates for HR-HPV with these two chips were significantly lower than 55.1% when HC2 was used. The sensitivity of overall HPV positivity in detecting histologically confirmed low-grade cervical squamous intraepithelial lesions or higher was 88.7% for all three tests. The specificity was 58.5% for 9G and 61.5% for PANArray, which was significantly lower than the 72.3% for HC2. With the HR-HPV(+) genotype threshold, the sensitivity decreased to 75.5% for 9G and 52.8% for PANArray, which was significantly lower than the 88.7% for HC2. Comparison of the two chips showed concordant results in 55.1% of the samples, compatible results in 16.9%, and discordant results in 28.0%, exhibiting poor agreement in detecting  certain HPV genotypes. Compared with direct sequencing, 9G yielded no discordant results, whereas PANArray yielded 31 discordant results (26.7%). CONCLUSIONS: Compared with HC2, the HPV genotyping tests showed lower sensitivity in histologic correlation. When the two chips were compared, the 9G was more sensitive and accurate for detecting HR-HPV than the PANArray.

DNA degradation in liquid-based cytology and its comparison with conventional smear.

BACKGROUND: In fine needle aspiration biopsy (FNAB) of thyroid nodules, LBC is adopted in most of the hospitals and clinics in Korea for its convenience. BRAF mutation test has been introduced as an important ancillary test, but its applicability has not been completely proven with LBC samples. METHODS: Five aspirates from thyroidectomy specimens were simultaneously processed into LBC and CS slides, in which BRAF mutation tests were performed using three primer sets with PCR products of 72, 164, and 226 base pairs (bp) at 6, 9, and 12 months after processing. In addition, BRAF mutation tests were performed in nine clinical samples that had been prepared by LBC or CS and stored for 3-5 years after processing. RESULTS: At 9 months after processing, LBC failed to provide DNA of sufficient quality for PCR, whereas CS succeeded with primers for amplifying a 226 bp fragment. Furthermore, CS had successful amplification of DNA despite a delay of more than 1 year. The failure of DNA amplification in LBC was overcome by using primers to amplify shorter PCR products, suggesting that DNA degradation occurred in LBC. However, false positive or negative results were observed in primers for amplifying shorter size. The kind of preservative solutions used in LBC did not affect test results. CONCLUSION: LBC may have disadvantages in long-term DNA preservation because of its accelerated DNA degradation compared with alcohol-fixed CS. Using primers to amplify shorter size fragments might be helpful in mitigating loss of signal due to DNA degradation in LBC.

The Natural Course of Endobronchial Inflammatory Polyps as a Complication after Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration.

We presented a case of unusual endobronchial inflammatory polyps as a complication following endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in a patient with tuberculous lymphadenitis. EBUS-TBNA of the right hilar lymph node was performed in a 29-year-old, previously healthy man. The patient was confirmed with tuberculous lymphadenitis and received antituberculosis medication over the course of 6 months. Chest computed tomography, after 6 months of antituberculosis therapy following the EBUS-TBNA showed nodular bronchial wall thickening of the right main bronchus. Histological and microbiological examinations revealed inflammatory polyps. After 7 months, the inflammatory polyps regressed almost completely without need for removal.

Efficiency of EGFR mutation analysis for small microdissected cytological specimens using multitech DNA extraction solution.

BACKGROUND: The microdissection method has greatly facilitated the isolation of pure cell populations for accurate analysis of mutations. However, the absence of coverslips in these preparations leads to poor resolution of cellular morphological features. In the current study, the authors developed the MultiTech DNA extraction solution to improve the visualization of cell morphology for microdissection and tested it for the preservation of morphological properties of cells, quality of DNA, and ability to detect mutations. METHODS: A total of 121 cytological samples, including fine-needle aspirates, sputum, pleural fluid, and bronchial washings, were selected from hospital archives. DNA extracted from microdissected cells was evaluated by epidermal growth factor receptor (EGFR) mutation analysis using pyrosequencing, Sanger sequencing, and peptide nucleic acid (PNA)-mediated real-time polymerase chain reaction clamping. Morphological features of cells as well as DNA quality and quantity were analyzed in several cytological samples to assess the performance of the MultiTech DNA extraction solution. The results were compared with previous EGFR mutation tests. RESULTS: The MultiTech DNA extraction solution improved the morphology of archived stained cells before microdissection and provided a higher DNA yield than the commercial QIAamp DNA Mini Kit in samples containing a minimal number of cells (25-50 cells). The authors were able to detect identical EGFR mutations by using different analysis platforms and consistently identified these mutations in samples comprising as few as 25 microdissected cells. CONCLUSIONS: The MultiTech DNA extraction solution is a reliable medium that improves the resolution of cell morphology during microdissection. It was particularly useful in EGFR mutations of samples containing a small number of cells.

Preoperative RAS mutational analysis is of great value in predicting follicular variant of papillary thyroid carcinoma.

Follicular variant of papillary thyroid carcinoma (FVPTC), particularly the encapsulated subtype, often causes a diagnostic dilemma. We reconfirmed the molecular profiles in a large number of FVPTCs and investigated the efficacy of the preoperative mutational analysis in indeterminate thyroid nodules. BRAF V600E/K601E and RAS mutational analysis was performed on 187 FVPTCs. Of these, 132 (70.6%) had a point mutation in one of the BRAF V600E (n=57), BRAF K601E (n=11), or RAS (n=64) genes. All mutations were mutually exclusive. The most common RAS mutations were at NRAS codon 61. FNA aspirates from 564 indeterminate nodules were prospectively tested for BRAF and RAS mutation and the surgical outcome was correlated with the mutational status. Fifty-seven and 47 cases were positive for BRAF and RAS mutation, respectively. Twenty-seven RAS-positive patients underwent surgery and all except one patient had FVPTC. The PPV and accuracy of RAS mutational analysis for predicting FVPTC were 96% and 84%, respectively. BRAF or RAS mutations were present in more than two-thirds of FVPTCs and these were mutually exclusive. BRAF mutational analysis followed by N, H, and KRAS codon 61 mutational analysis in indeterminate thyroid nodules would streamline the management of patients with malignancies, mostly FVPTC.

A Case of Multifocal Papillary Thyroid Carcinoma Consisting of One Encapsulated Follicular Variant with BRAF K601E Mutation and Three Conventional Types with BRAF V600E Mutation.

Multifocal papillary thyroid carcinoma (mPTC) comprises about 20-30% of PTC. In mPTC, individual tumor foci can be identical or frequently composed of different histological types including follicular, solid, tall-cell or conventional patterns. We report a case of mPTC consisting of one encapsulated follicular variant of papillary thyroid carcinoma (FVPTC) and three conventional PTCs in a 44-year-old woman. This case genetically demonstrates unique features including the simultaneous presence of the BRAF V600E (T1799A) mutation and the BRAF K601E (A1801G) mutation in conventional PTC and FVPTC, respectively.

Development of an ammonium sulfate DNA extraction method for obtaining amplifiable DNA in a small number of cells and its application to clinical specimens.

DNA extraction from microdissected cells has become essential for handling clinical specimens with advances in molecular pathology. Conventional methods have limitations for extracting amplifiable DNA from specimens containing a small number of cells. We developed an ammonium sulfate DNA extraction method (A) and compared it with two other methods (B and C). DNA quality and quantity, ß-globin amplification, and detectability of two cancer associated gene mutations were evaluated. Method A showed the best DNA yield, particularly when the cell number was very low. Amplification of the ß-globin gene using DNA from the SNU 790 cell line and papillary thyroid carcinoma (PTC) cells extracted with Method A demonstrated the strongest band. BRAF(V600E) mutation analysis using ethanol-fixed PTC cells from a patient demonstrated both a "T" peak increase and an adjacent "A" peak decrease when 25 and 50 cells were extracted, whereas mutant peaks were too low to be analyzed using the other two methods. EGFR mutation analysis using formalin-fixed paraffin-embedded lung cancer tissues demonstrated a mutant peak with Method A, whereas the mutant peak was undetectable with Methods B or C. Method A yielded the best DNA quantity and quality with outstanding efficiency, particularly when paucicellular specimens were used.

Clinical investigation of EGFR mutation detection by pyrosequencing in lung cancer patients.

Direct sequencing is the standard method for the detection of epidermal growth factor receptor (EGFR) mutations in lung cancer, however, its relatively low sensitivity limits its clinical use. Pyrosequencing is a bioluminometric, real-time non-electrophoretic DNA sequencing technique with a number of advantages compared with direct sequencing, including higher sensitivity, speed, automation and cost-effectiveness. Clinical specimens from 202 lung cancer patients were analyzed for EGFR mutations in exons 18, 19, 20 and 21 using the pyrosequencing method following genomic DNA extraction from paraffin-embedded tissue specimens. All clinical data and tumor specimens were obtained from the Konkuk University Hospital (Korea) between July 2006 and December 2008. The results and clinical responses to EGFR-tyrosine kinase inhibitors (TKIs) were compared. Overall, EGFR mutation-positive rate was 26.7% (54/202). Activating EGFR mutations were observed more frequently in female (52.1 vs. 13.0%), non-smoking (47.8 vs. 15.8%) and adenocarcinoma (35.2 vs. 5.2%) patients. However, significant numbers of EGFR mutation-positive patients were identified as male, former or current smokers and non-adenocarcinoma patients. The combinations of favorable clinicopathological factors, including female, non-smoking and adenocarcinoma, were not identified to significantly increase the positive EGFR mutation rate (female, 52.1%; female and non-smoker, 52.6%; female, non-smoker and adenocarcinoma, 51.9%). The present findings indicate that EGFR mutation analysis is a highly useful method for the prediction of response to EGFR-TKI and the use of favorable clinicopathological factors to perform this analysis is not suitable. Exon 19 deletion was the most common mutation (63.6%) and exon 21 L858R substitution was measured at 32.7%. The exon 20 T790M mutation was identified in 1 patient prior to EGFR-TKI treatment. EGFR mutation status is associated with response to EGFR-TKI and the overall response rate in patients who have the activating EGFR mutation was 82.4 vs. 5.9% in patients with a wild-type EGFR. The present study demonstrates that EGFR mutations analyzed by the pyrosequencing method are well correlated with clinicopathological parameters and that this method may be useful in the clinical practice.

Primary pure squamous cell carcinoma of the thyroid: report and histogenic consideration of a case involving a BRAF mutation.

Primary squamous cell carcinoma of the thyroid (SCC-T) is extremely rare. Its clinical presentation is similar to that of anaplastic carcinoma. Metastasis or extension from the head and neck area should be ruled out, as patients with SCC-T have a poorer prognosis than patients who have a thyroid extension from an adjacent tumor. An 87-year-old man presented with a longstanding painless mass in the right thyroid and had experienced 2 months of pain upon swallowing. A right lobectomy was performed with resection of thyroid cartilage, cricoid cartilage, a portion of the first to third tracheal ring and the right neck lymph node. A histological examination revealed pure SCC. The tumor cells showed diffuse immunoreactivity to CK5/6, CK19 and p63. Immunoreactivity to EMA and p53 was focally positive. TTF-1, galectin 3 and thyroglobulin immunoreactivity was restricted to the non-neoplastic thyroid tissue. Both tumor cells and non-neoplastic follicular cells were negative for CD5. The MIB-1 index was 36%. DNA extracted from the tumor identified a BRAF V600E mutation in exon 15 and a BRAF G468A mutation in exon 11, whereas DNA from non-tumorous cells did not contain a mutation. These molecular findings may suggest a direct transformation from papillary carcinoma to SCC-T.

Pyrosequencing analysis for detection of a BRAFV600E mutation in an FNAB specimen of thyroid nodules.

BACKGROUND: Fine-needle aspiration biopsy (FNAB) is the primary means of distinguishing benign from malignant and of guiding therapeutic intervention in thyroid nodules. However, 10% to 30% of cases with indeterminate cytology in FNAB need other diagnostic tools to refine diagnosis. OBJECTIVE: We compared the pyrosequencing method with the conventional direct DNA sequencing analysis and investigated the usefulness of preoperative BRAF mutation analysis as an adjunct diagnostic tool with routine FNAB. METHODS: A total of 103 surgically confirmed patients' FNA slides were recruited and DNA was extracted after atypical cells were scraped from the slides. BRAF mutation was analyzed by pyrosequencing and direct DNA sequencing. RESULTS: Sixty-three (77.8%) of 81 histopathologically diagnosed malignant nodules revealed positive BRAF mutation on pyrosequencing analysis. In detail, 63 (84.0%) of 75 papillary thyroid carcinoma (PTC) samples showed positive BRAF mutation, whereas 3 follicular thyroid carcinomas, 1 anaplastic carcinoma, 1 medullary thyroid carcinoma, and 1 metastatic lung carcinoma did not show BRAF mutation. None of 22 benign nodules had BRAF mutation in both pyrosequencing and direct DNA sequencing. Out of 27 thyroid nodules classified as 'indeterminate' on cytologic examination preoperatively, 21 (77.8%) cases turned out to be malignant: 18 PTCs (including 2 follicular variant types) and 3 follicular thyroid carcinomas. Among these, 13 (61.9%) classic PTCs had BRAF mutation. None of 6 benign nodules, including 3 follicular adenomas and 3 nodular hyperplasias, had BRAF mutation. Among 63 PTCs with positive BRAF mutation detected by pyrosequencing analysis, 3 cases did not show BRAF mutation by direct DNA sequencing. Although it was not statistically significant, pyrosequencing was superior to direct DNA sequencing in detecting the BRAF mutation of thyroid nodules (P=0.25). CONCLUSION: Detecting BRAF mutation by pyrosequencing is more sensitive, faster, and less expensive than direct DNA sequencing and is proposed as an adjunct diagnostic tool in evaluating thyroid nodules of indeterminate cytology.