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Abstract A large proportion of colorectal carcinomas (CRC) evolve from colorectal adenomas. However, not all individuals with colonic adenomas have a risk of CRC substantially higher than those of the general population. The aim of the study was to determine the differences or similarities of mutation profile among low- and high-grade adenomas and in situ carcinoma with detailed follow up. We have investigated the mutation spectrum of well-known genes involved in CRC (such as APC, BRAF, EGFR, NRAS, KRAS, PIK3CA, POLE, POLD1, SMAD4, PTEN, and TP53) in a large, well-defined series of 96 adenomas and in situ carcinomas using a high-throughput genotyping technique. Besides, the microsatellite instability and APC and MLH1 promoter methylation were studied as well. We observed a high frequency of pathogenic variants in the studied genes. The APC, KRAS and TP53 mutation frequencies were slightly lower in adenoma samples than in in situ carcinoma samples. Further, when we stratified mutation frequency based on the grade, the frequency distribution was as follows: low-grade adenoma—high-grade adenomas—in situ carcinoma: APC gene 42.9–56.0–54.5%; KRAS gene 32.7–32.0–45.5%; TP53 gene 8.2–20.0–18.2%. The occurrence of KRAS mutation was associated with the presence of villous histology and methylation of the APC promoter was significantly associated with the presence of POLE genetic variations. However, no association was noticed with the presence of any singular mutation and occurrence of subsequent adenoma or CRC. Our data supports the multistep model of gradual accumulation of mutations, especially in the driver genes, such as APC, TP53 and KRAS.

The electronic spectra of carbon nanotubes and other nanoscale systems are quantized because of their small radii. Similar quantization in the phonon spectra has been difficult to observe because of [...]

Objective: The aim of the study was to determine the optimum cut-off value of the quantitative immunochemical test (q-FIT) OC-Sensor for colorectal cancer and advanced adenomatous polyps in a particular population., Methods: 815 patients were referred for colonoscopy and were offered two q-FIT examinations at two different colonoscopy centers. The patients were classified according to the colonoscopic findings. Test sensitivity, specificity, and accuracy were statistically evaluated using one test and two tests at the levels of 50, 75, 100, 125, and 150 ng/mL of faecal hemoglobin in those patients with advanced polyps and colorectal cancer. The optimum cut-off test level for clinically significant neoplasia was determined using one test., Results: The optimum cut-off value of q-FIT OC-Sensor for the detection of clinically significant neoplasia in our particular population was determined as 75 ng/mL using one test. This value provides an optimum proportion of 73% sensitivity (±95% CI 60.3% - 83.4%) and 90% specificity (±95% CI 86.8% - 92.8%), PPV and NPV were determined as 54.76% and 95.43% respectively., Conclusions: The first step in the implementation of q-FIT test in the screening program in our country is to determine the optimum cut-off level for a population, and to estimate the number of tests performed with respect to the optimum cost effectiveness and economical climate. Using one test, the optimum level of q-FIT OC-Sensor® in the Czech Republic was determined as 75 ng/mL. This study could serve as a model for further studies in other countries, where screening does not yet exist.

Calreticulin, upon translocation to the cell surface, plays a critical role in the recognition of tumour cells and in experimentally induced cellular anti-tumour immunity. However, less is known about anti-calreticulin antibodies and their role in malignancies. Using enzyme-linked immunosorbent assay (ELISA), we found immunoglobulin (Ig)A and/or IgG anti-calreticulin antibodies in sera of approximately 63% of patients with hepatocellular carcinoma (HCC), 57% of patients with colorectal adenocarcinoma (CRA) and 47% of patients with pancreatic adenocarcinoma (PACA), while healthy controls, patients with viral hepatitis C and with chronic pancreatitis reached only 2%, 20% and 31% seropositivity, respectively. We found significantly elevated mean levels of IgA anti-calreticulin antibodies (P < 0.001) in patients with HCC (78.7 +/- 52.3 AU, mean +/- standard deviation), PACA (66.5 +/- 30.9 AU) and CRA (61.8 +/- 25.8 AU) when compared to healthy controls (41.4 +/- 19.2 AU). Significantly elevated mean levels of IgG anti-calreticulin antibodies (P < 0.001) were detected in patients with HCC (121.9 +/- 94.2 AU), gall bladder adenocarcinoma (118.4 +/- 80.0 AU) and PACA (88.7 +/- 55.6 AU) when compared to healthy controls (56.7 +/- 22.9 AU). Pepscan analysis revealed a large number of antigenic epitopes of calreticulin recognized by both IgA and IgG antibodies of patients with HCC and PACA, indicating robust systemic immune response. Moreover, significantly elevated levels of antibodies against peptide KGEWKPRQIDNP (P < 0.001) in these patients, tested by ELISA, confirmed the distinct character of antibody reactivity against calreticulin. The high occurrence and specificity of serum anti-calreticulin autoantibodies in the majority of patients with some gastrointestinal malignancies provide the evidence for their possible clinical relevance.

Vanek's tumor (inflammatory fibroid polyp) is a rare benign lesion occurring throughout the digestive tract. Histologically, two patterns can be recognized. Classical Vanek's tumor contains concentric formations of proliferating spindle cells which are CD34 positive. Atypical, inflammatory pseudotumor-like Vanek's tumor lacks concentric formations and is CD34 negative. Recently, mutations in platelet-derived growth factor receptor alpha (PDGFRA) were reported in gastric and small intestinal Vanek's tumors. In this study, KIT exons 9, 11, 13, and 17, PDGFRA exons 12, 14, and 18, and a part of exon 15 BRAF for point mutation V600E were screened in 23 cases of Vanek's tumor, both classical (n = 16) and inflammatory pseudotumor-like (n = 7). No mutations in all analyzed exons of KIT and BRAF and in exon 14 of PDGFRA were detected. Six Vanek's tumors harbored activating mutations in PDGFRA exons 12 (n = 5) and 18 (n = 1) respectively: S566&#95;E571delinsK (n = 1), S566&#95;E571delinsR (n = 4), and D842 del (n = 1). The mutations were detected in the classical (n = 5), as well as inflammatory pseudotumor-like (n = 1) Vanek's tumors. The results of this study suggest that the two morphological patterns of Vanek's tumor more probably represent only variants of one type of tumor than two different lesions. Furthermore, BRAF mutations were not shown to drive growth of PDGFRA wild-type Vanek's tumors.

Oral sodium phosphate (NaP) has been increasingly used for bowel preparation before the colonoscopy because it shows good patients tolerance and effective bowel cleansing ability. However, new studies describe that NaP can induce colonic mucosal damage. For better characterization of these changes, we examined histologically segmental colonic biopsies from 42 patients receiving NaP bowel solution before the colonoscopy. The series includes 25 male and 17 female patients in age from 19 to 81 years (average age 46.7 ys). Clinical symptoms in 37 patients included diarrhea, constipation, bleeding and abdominal cramps. The most frequent reason for colonoscopy was suspicion of microscopic colitis. Five patients underwent endoscopy to rule out the presence of neoplasia. None of the patients took drugs before the colonoscopy. Histologically, all specimens showed mild focal edema, hyperemia and hemorrhages. In addition to edema and hemorrhage, in 26 patients (61.9%), patchy mononuclear infiltration in the upper part of lamina propria and increased epithelial cell proliferation of individual crypts were seen. Mucosal structure was normal, with partial sloughing of normal or flattened surface epithelium. In 5 patients (11.9%), some biopsy samples contained scattered neutrophilic leucocytes in the lamina propria/superficial epithelium, isolated basal cryptitis, increased proliferation and apoptosis of the crypt epithelium. In two patients with focal cryptitis (4.8%), small erosions were found. Mild basal cryptitis, increased proliferation and striking apoptosis were present in two inflammatory pseudopolyps (in two patients). In 4 patients, solitary tubular adenomas with low-grade dysplasia without any reactive changes were found. In addition, 300 hyperplastic polyps removed endoscopically after the NaP application, were examined. Two polyps (0.75%) showed cryptitis and isolated multinucleated epithelial cells in the superficial part of the crypts. Our results are similar to those previously described in other studies of colonic changes after the NaP application. It reflects probably a similarity in composition of used NaP solutions.

Background: It has been established that the removal of adenomatous colon polyps drastically reduces the incidence of colorectal cancer (CRC), but polypectomy is not without risk. The aim was to determine the correlation between the results of an optical biopsy system and the histopathology report of the physical biopsy specimens of the same polyps removed at colonoscopy., Patients and Methods: Paired optical and physical biopsies were performed on 55 polyps with complete polypectomy of the same tissue., Results: Fifty-three adenomatous polyps and two hyperplastic polyps were identified by the hospital pathologist. The optical biopsy system identified 52 polyps as suspect (adenomatous) and 2 as non-suspect (hyperplastic). One villous adenoma could not be optically analyzed due to friability., Conclusion: The WavSTAT Optical Biopsy System provides accurate information to the gastroenterologist to assist in distinguishing between hyperplastic and adenomatous polyps. It is safe for the patient and does not unduly increase the time required for an endoscopic examination.

Objective: It is an open question whether multifunctional galectin-3 can be a serum marker in inflammatory bowel disease., Methods: Western blots and commercial ELISA detected and quantitated the lectin immunocytochemistry using double labeling localized it in tissue sections., Results: Serum concentrations were significantly increased in specimen of patients with active and remission-stage ulcerative colitis and Crohn's disease, associated with emerging positivity of CD14(+) cells., Conclusion: Enhanced concentration of galectin-3 in serum reflects presence of disease and points to its involvement in the pathogenesis.

Refractory coeliac disease (RCD) is a very rare and dangerous form of CD, in which gluten-free diet loses its therapeutic effect and the damage of intestinal mucosa persists. Because of the adherence to the diet, serological markers of CD [immunoglobulin A (IgA) antibodies against gliadin, tissue transglutaminase (tTG) and endomysium] are often missing in RCD patients. We found substantially elevated levels of IgA anti-calreticulin (CRT) antibodies in the sera of almost all RCD patients tested. These sera were negative for IgA antibodies to gliadin and tTG and only some of them showed IgA antibodies to enterocytes. Analysis of patients' IgA reactivity to CRT fragments (quarters and halves) by Western blotting revealed differences in the specificity of IgA antibodies between RCD and CD patients. We therefore used the Pepscan technique with synthetic overlapping decapeptides of CRT to characterize antigenic epitopes recognized by serum IgA antibodies of RCD patients. Employing this method we demonstrated several dominant antigenic epitopes recognized by IgA antibodies of RCD patients on the CRT molecule. Epitope GVTKAAEKQMKD was recognized predominantly by serum IgA of RCD patients. Our results suggest that testing for serum IgA antibodies against CRT and its selected peptide could be a very useful tool in RCD differential diagnosis.