Clinicopathological features and BRAFV600E mutation analysis in colorectal cancer

The CpG Island Methylator Phenotype and Chromosomal Instability Are Inversely Correlated in Sporadic Colorectal Cancer

A Prospective, Multicenter, Population-Based Study of BRAF Mutational Analysis for Lynch Syndrome Screening

Molecular HLA typing--the brave new world.

Microsatellite Instability Testing in Colorectal Carcinoma: A Practical Guide

This study aimed to evaluate the diagnostic value of BRAFV600E mutation and DNA ploidy determination for Papillary Thyroid Micro-Carcinoma (PTMC) through fine-needle aspiration. Clinical data, including histology, patient population statistics and clinical results were gathered. Patients’ thyroid-micro-lesions were made into FNA-stained smears, DNA was extracted from the smears for different cytological diagnoses. BRAFV600E mutation was detected by Amplification Refractory Mutation System (ARMS). DNA ploidy determination of PTMC was detected by DNA quantitative analyser. All surgical cases were collected for histopathological diagnosis. BRAFV600E mutation was identified in 168 of 180 (93.3%) of PTMC, 0/9 of thyroid follicular carcinomer and 0/1389 of benign thyroid nodules. 127/180 (70.5%) patients got a definitive diagnosis of PTMC when only use cytology. 177/180 (98.3%) patients got a definitive diagnosis of PTMC by a combination of cytology and BRAFV600E mutation analysis (p<0.05). DNA ploidy determination showed no abnormal on papillary thyroid microcarcinoma. BRAFV600E mutation could be only detected in Papillary Thyroid Carcinoma (PTC) patients and is the most common oncogenic alteration in PTC patients. Thus BRAFV600E mutation is a genetic marker of PTMC. BRAFV600E mutation analysis via fine-needle aspiration improved 27.8% of the diagnosis rate of PTMC when combined with cytology.

Association of Metabolic Syndrome With Proximal and Synchronous Colorectal Neoplasm

Microsatellite Instability in Interval Colon Cancers

Objective To evaluate the feasibility of the combination of amplification refractory mutation system (ARMS) and quantitative real-time polymerase chain reaction (PCR) method in fast detection of clarithromycin resistance of Helicobacter pylori (H.pylori) in gastric mucosa. Methods A total of 150 gastric mucosal specimens with positive H. pylori culture were collected from the H. pylori positive patients who failed in H. pylori eradication from January to August in 2013. The drug resistant gene mutation types of H. pylori in these samples were detected by quantitative real-time PCR based on ARMS. And the accuracy was confirmed by sequencing. The clarithromycin resistance of H. pylori was determined by E-assay. Chi-square test was used for statistical analysis. Results Among 149 gastric mucosal specimens (one specimens without wild type or mutation type had been eliminated), the results of quantitative real-time PCR based on ARMS of two samples were not consistent with the results of sequencing; the consistent rate was 98.7% (147/149). Among 149 specimens with positive H. pylori culture, 104 samples (69.8%) were clarithromycin resistance. In 101 samples the clarithromycin resistance was detected by quantitative real-time PCR based on ARMS; the consistent rate was 97.1% (101/104). Both E-assay and clarithromycin resistant rate detected by E-assay or quantitative real-time PCR based on ARMS was 69.8% (104/149) and 67.8% (101/149), respectively, and the difference was not significant (χ2=0.141, P=0.932). Conclusion The combination of ARMS and quantitative real-time PCR method in fast detection of clarithromycin resistance of H. pylori in gastric mucosa is strongly feasible and highly consistent has high consistent rate with sequencing and E-assay. Key words: Helicobacter pylori; Amplification refractory mutation system; Mutation; Resistance

Detection of the JAK2 V617F Mutation by LightCycler PCR and Probe Dissociation Analysis

Immunohistochemical Expression of MYH Protein Can Be Used to Identify Patients With MYH-Associated Polyposis

BackgroundThe accurate evaluation of BRAFV600E mutation in preoperative fine‐needle aspiration cytology (FNAC) specimens is important for making management decisions in thyroid nodules (TNs). The aim of this study was to assess the false‐positive and false‐negative BRAFV600E mutations in thyroid FNAC specimens and their influence on diagnosis of TN.MethodsThis prospective study enrolled 292 nodules in 269 patients who underwent BRAFV600E mutation analysis using amplification refractory mutation system‐quantitative real‐time polymerase chain reaction (ARMS‐qPCR) both in FNAC specimens and formalin‐fixed, paraffin‐embedded (FFPE) tissue samples after surgery. The false‐positive and false‐negative mutations for BRAFV600E analysis using ARMS‐qPCR in FNAC specimens were recorded, with reference to the results of BRAFV600E mutation analysis using ARMS‐qPCR in FFPE tissue sample. Diagnostic performances of FNAC, BRAFV600E mutation analysis in FNAC specimens, BRAFV600E mutation analysis in FFPE tissue sample, and the combination of FNAC and BRAFV600E mutation analysis for predicting thyroid malignancy were assessed.ResultsThe false‐positive and false‐negative mutations for BRAFV600E analysis using ARMS‐qPCR in FNAC specimens were 10.1% (19/189) and 7.1% (7/98), respectively. FNAC combined with preoperative BRAFV600E mutation analysis significantly increased the diagnostic sensitivity from 75.7% to 92.3%, and accuracy from 78.7% to 90.6% in comparison with FNAC alone (both P < .001). No significant differences were found between the combination of FNAC and BRAFV600E mutation analysis in FNAC specimens and the combination of FNAC and BRAFV600E mutation analysis in FFPE tissue sample (sensitivity: 92.3% vs 91.9%; accuracy: 90.6% vs 91.3%; both P > .05).ConclusionsFNAC combined with preoperative BRAFV600E mutation analysis can significantly increase the diagnostic performance in comparison with FNAC alone. False‐positive and false‐negative BRAFV600E mutation results are found in preoperative FNAC specimens, whereas it does not affect the overall auxiliary diagnosis of TNs.

To determine the prognostic significance of deficient mismatch repair (dMMR) and BRAF V600E in Thai sporadic colorectal cancer (CRC) patients. We studied a total of 211 out of 405 specimens obtained from newly diagnosed CRC patients between October 1, 2006 and December 31, 2007 at Siriraj Hospital, Mahidol University. Formalin-fixed paraffin-embedded blocks of CRC tissue samples were analyzed for dMMR by detection of MMR protein expression loss by immunohistochemistry or microsatellite instability using polymerase chain reaction (PCR)-DHPLC. BRAF V600E mutational analysis was performed in DNA extracted from the same archival tissues by two-round allele-specific PCR and analyzed by high sensitivity DHPLC. Associations between patient characteristics, MMR and BRAF status with disease-free survival (DFS) and overall survival (OS) were determined by Kaplan-Meier survival plots and log-rank test together with Cox's proportional hazard regression. dMMR and BRAF V600E mutations were identified in 31 of 208 (14.9%) and 23 of 211 (10.9%) tumors, respectively. dMMR was more commonly found in patients with primary colon tumors rather than rectal cancer (20.4% vs 7.6%, P =0.01), but there was no difference in MMR status between the right-sided and left-sided colon tumors (20.8% vs 34.6%, P = 0.24). dMMR was associated with early-stage rather than metastatic disease (17.3% vs 0%, P = 0.015). No clinicopathological features such primary site or tumor differentiation were associated with the BRAF mutation. Six of 31 (19.3%) samples with dMMR carried the BRAF mutation, while 17 of 177 (9.6%) with proficient MMR (pMMR) harbored the mutation (P = 0.11). Notably, patients with dMMR tumors had significantly superior DFS (HR = 0.30, 95%CI: 0.15-0.77; P = 0.01) and OS (HR = 0.29, 95%CI: 0.10-0.84; P = 0.02) compared with patients with pMMR tumors. By contrast, the BRAF V600E mutation had no prognostic impact on DFS and OS. The prevalence of dMMR and BRAF V600E in Thai sporadic CRC patients was 15% and 11%, respectively. The dMMR phenotype was associated with a favorable outcome.

Objective To investigate the role of BRAFV600E mutation in diagnosis of thyroid nodules when it is inconsonant with cytological results. Methods This study included 9837 patients who underwent US-FNA. We mainly analyzed 239 cases with benign or indeterminate cytology, but having a detection of BRAFV600E mutation. BRAFV600E mutation analysis was performed using a Amplification Refractory Mutation System Polymerase Chain Reaction. Results In 93 nodules with benign cytology results but positive BRAFV600E mutation, 84 nodules were malignant. Based on the results, US-FNA combined with BRAFV600E mutation analysis will improve sensitivity (Se=94.03%) and negative predictive value (NPV=2.69%) of the thyroid nodules diagnosis than using US-FNA alone (Se=71.03%, NPV=20.76%) . Conclusion BRAFV600E mutation analysis is an important tool in the diagnosis of PTC with high sensitivity and NPV. When facing patients with benign or indeterminate cytology but positive BRAFV600E mutation, thyroidectomy should be considered. Key words: Thyroid cancer; BRAFV600E mutation; Benign cytology; Indeterminate cytology

Colorectal Cancer Risks in Relatives of Young-Onset Cases: Is Risk the Same Across All First-Degree Relatives?

To evaluate the clinical role of BRAF V600E mutation testing in fine-needle aspirates (FNA) of thyroid nodules. This study included 83 nodules in 80 patients who underwent FNA from March 2013 to September 2013. Cytological specimens were collected and BRAF exon 15 was examined by polymerase chain reaction (PCR). DNA sequencing and analysis were performed. Diagnostic performances of cytology and cytology with BRAF V600E mutation analysis were compared according to postoperative pathological diagnosis. The relation of BRAF V600E mutation with clinical factors including sex and age of patients, tumor size, lymph node metastasis, multifocality, and AJCC stage were analyzed. Of 83 nodules, 33 nodules were clinically observed, and 48 nodules underwent surgery, and suggestions of surgery were refused in 2 nodules. Among 48 nodules with surgery, BRAF V600E mutation was found in 25 nodules with histologic confirmation of papillary thyroid carcinoma after thyroidectomy, 13 of the 25 nodules were cytologically diagnosed as carcinoma and 12 were indeterminate. Among the 23 BRAF V600E negative noodles, 5 were cytologically diagnosed as carcinoma, 2 were benign, and 16 were indeterminate; 15 nodules were histologic confirmation of papillary thyroid carcinoma after thyroidectomy, 1 nodule was medullary thyroid carcinoma, and 7 nodules were benign. Biomolecular analysis significantly increased cytology sensitivity for papillary thyroid carcinoma from 43.9% to 73.2% (P < 0.05). Direct DNA sequencing showed that the presence of BRAF V600E mutation was 62.5% in 40 thyroid papillary nodules. There were 16 BRAF-positive nodules (80.0%) among 20 papillary thyroid nodules with extrathyroidal extension, however there were 9 BRAF-negative nodules (45.0%) among 20 papillary thyroid nodules without extrathyroidal extension. Univariate analysis indicated the BRAF V600E mutation was associated with extrathyroidal extension (χ² = 5.227, P = 0.022), but not with sex, age, tumor size, lymph node metastasis, multifocality and AJCC stage. BRAF V600E mutation analysis can significantly improve FNA diagnostic accuracy and maybe useful for prediction of high-risk of thyroid carcinoma.