Relationship Between Immunophenotypes, Genetic Profiles, and Clinicopathologic Characteristics in Small Bowel Adenocarcinoma.

Small bowel adenocarcinoma (SBA) is rare, and scant data exist regarding its molecular and clinicopathologic characteristics. This study aimed to clarify the correlation between immunophenotypes, DNA mismatch repair status, genomic profiling, and clinicopathologic characteristics in patients with SBA. We examined 68 surgical resections from patients with primary SBA for immunohistochemical analyses of CK7, CK20, CD10, CDX2, MUC1, MUC2, MUC4, MUC5AC, and MUC6 expression as well as mismatch repair status. Genomic profiling was performed on 30 cases using targeted next-generation sequencing. Tumor mucin phenotypes were classified as gastric, intestinal, gastrointestinal, or null based on MUC2, MUC5AC, MUC6, and CD10 immunostaining. The expression of these proteins was categorized into 3 classifications according to their relationship to: (1) tumor location: CK7/CK20, MUC4, and MUC6; (2) histologic type: mucinous adenocarcinoma was positive for MUC2 and negative for MUC6; and (3) TNM stage: CD10 was downregulated, whereas MUC1 was upregulated in advanced TNM stages. CDX2 was a specific marker for SBA generally expressed in the small intestine. MUC1 and MUC4 expression was significantly associated with worse prognosis. MUC2 expression correlated with better prognosis, except for mucinous adenocarcinoma. Although the difference was not statistically significant, gastric-type tumors were more frequently located in the duodenum and were absent in the ileum. APC and CTNNB1 mutations were not found in the gastric-type tumors. The SBA immunophenotype correlated with tumor location, biological behavior, and genomic alterations. Our results suggest that the molecular pathway involved in carcinogenesis of gastric-type SBA differs from that of intestinal-type SBA.

Clinical significance of programmed cell death-ligand expression in small bowel adenocarcinoma is determined by the tumor microenvironment.

BACKGROUND: Comprehensive genomic analysis has shown that small bowel adenocarcinoma (SBA) has different genomic profiles from gastric and colorectal cancers. Hence, it is essential to establish chemotherapeutic regimens based on SBA characteristics. The expression of programmed cell death-ligand 1 (PD-L1) and programmed cell death-ligand 2 (PD-L2) in SBA is not fully understood. Anti-PD-L1/PD-1 therapy uses tumor-infiltrating lymphocytes (TILs); therefore, the status of TILs in the tumor microenvironment (TME) may influence their efficacy. The ratio of FoxP3+ to CD8+ T cells has been reported to be useful in predicting the prognosis of digestive system cancers. AIM: To investigate the clinicopathological significance of PD-L1/2 expression according to the status of TILs in SBA tissues. METHODS: We performed immunohistochemical analysis for PD-L1, PD-L2, CD8, FoxP3, and DNA mismatch repair (MMR) proteins using formalin-fixed, paraffin-embedded tissues from 50 patients diagnosed with primary SBA. The immunoreactivities of PD-L1 and PD-L2 were determined separately in tumor cells and tumor-infiltrating immune cells throughout the tumor center and invasive margins, and finally evaluated using the combined positive score (CPS). We assessed CD8+ and FoxP3+ T cells in the intratumoral and tumor-surrounding stroma. Subsequently, we calculated and summed the ratio of FoxP3 to CD8+ T cell counts. Immune-related cell densities were graded as low or high. Immunohistochemical results were compared with clinicopathological factors and patient prognosis. The distribution of cancer-specific survival (CSS) was estimated using the Kaplan-Meier method, and the log-rank test was used to test for significant differences in CSS. A Cox proportional hazard model was also used to assess the effect of tumor variables on CSS. RESULTS: PD-L1 expression was positive in 34% in tumor cells (T-PD-L1) and 54% in tumor-infiltrating immune cells (I-PD-L1) of the cases examined. T-PD-L2 was positive in 34% and I-PD-L2 was positive in 42% of the cases. PD-L1 CPS ≥ 10 and PD-L2 CPS ≥ 10 were observed in 50% and 56% of the cases, respectively. Deficient MMR (dMMR) was 14% of the cases. T-PD-L1, I-PD-L1 and PD-L1 CPS ≥ 10 were all significantly associated with dMMR (P = 0.037, P = 0.009, and P = 0.005, respectively). T-PD-L1, I-PD-L1, and PD-L1 CPS ≥ 10 were all associated with deeper depth of invasion (P = 0.001, P = 0.024, and P = 0.002, respectively). I-PD-L2 expression and PD-L2 CPS ≥ 10 were significantly higher in the differentiated histological type (P = 0.015 and P = 0.030, respectively). The I-PD-L1 and I-PD-L2 levels were significantly associated with better CSS (P = 0.037 and P = 0.015, respectively). CD8-high was significantly associated with less lymph node metastasis (P = 0.047), less distant metastasis (P = 0.024), less peritoneal dissemination (P = 0.034), and earlier TNM stage (P = 0.047). The CD8-high group had better prognosis than the CD8-low group (P = 0.018). FoxP3 expression was not associated with any clinicopathological factors or prognosis. We found that patients with PD-L2 CPS ≥ 10 tended to have worse prognosis in the FoxP3/CD8-low group (P = 0.088). CONCLUSION: The clinicopathological significance of PD-L1/2 expression may differ depending on the TME status. Immune checkpoint inhibitors may improve the prognosis of SBA patients with low FoxP3/CD8 ratio and PD-L2 expression.

Comparison of Linked Color Imaging and White Light Imaging Colonoscopy for Detection of Colorectal Adenoma Requiring Endoscopic Treatment: A Single-Center Randomized Controlled Trial.

BACKGROUND: Linked color imaging (LCI) improves detection of colorectal neoplastic lesions during colonoscopy. However, polyps <5 mm in diameter often do not require resection, and the benefits of LCI are unclear for detection of colorectal polyps ≥5 mm that are indicated for endoscopic resection in clinical practice. This randomized controlled trial compared rates of detection of adenoma polyps, stratified by size, for LCI and white light imaging (WLI). METHODS: We compared ADR (5 mm-) and PDR (5 mm-), which were defined as the proportion of patients with at least one adenoma or polyp with a diameter of 5 mm or larger in the LCI and WLI groups. Moreover, we estimated ADR and PDR for diameters between 5 and 10 mm (ADR (5-9 mm), PDR (5-9 mm) ) and for diameters larger than 10 mm (ADR (10 mm-), PDR (10 mm-) ). RESULTS: Data from 594 patients (LCI, n=305; WLI, n=289) were analyzed. ADR (5 mm-) and PDR (5 mm-) were significantly higher in the LCI group than in the WLI group (ADR (5 mm-): P=0.016, PDR (5 mm-): P=0.020). In the assessment of adenoma and polyp size, ADR (5-9 mm) and PDR (5-9 mm) were significantly higher in the LCI group than in the WLI group, although no significant differences were seen in ADR (10 mm-) and PDR (10 mm-) between these groups. CONCLUSIONS: Polyps ≥5 mm, which are indicated for endoscopic treatment, were more easily visualized with LCI mode than with WLI mode. The improvement in detection rate was obvious for polyps <10 mm, which are easier to miss.

Risk factors for small intestinal adenocarcinomas that are common in the proximal small intestine.

The frequency of primary small intestinal adenocarcinoma is increasing but is still low. Its frequency is approximately 3% of that of colorectal adenocarcinoma. Considering that the small intestine occupies 90% of the surface area of the gastrointestinal tract, small intestinal adenocarcinoma is very rare. The main site of small intestinal adenocarcinoma is the proximal small intestine. Based on this characteristic, dietary animal proteins/lipids and bile concentrations are implicated and reported to be involved in carcinogenesis. Since most nutrients are absorbed in the proximal small intestine, the effect of absorbable intestinal content is a suitable explanation for why small intestinal adenocarcinoma is more common in the proximal small intestine. The proportion of aerobic bacteria is high in the proximal small intestine, but the absolute number of bacteria is low. In addition, the length and density of villi are greater in the proximal small intestine. However, the involvement of villi is considered to be low because the number of small intestinal adenocarcinomas is much smaller than that of colorectal adenocarcinomas. On the other hand, the reason for the low incidence of small intestinal adenocarcinoma in the distal small intestine may be that immune organs reside there. Genetic and disease factors increase the likelihood of small intestinal adenocarcinoma. In carcinogenesis experiments in which the positions of the small and large intestines were exchanged, tumors still occurred in the large intestinal mucosa more often. In other words, the influence of the intestinal contents is small, and there is a large difference in epithelial properties between the small intestine and the large intestine. In conclusion, small intestinal adenocarcinoma is rare compared to large intestinal adenocarcinoma due to the nature of the epithelium. It is reasonable to assume that diet is a trigger for small intestinal adenocarcinoma.

Genetic analysis of Japanese patients with small bowel adenocarcinoma using next-generation sequencing.

BACKGROUND: Small bowel adenocarcinomas (SBAs) are rare and there is little comprehensive data on SBA genomic alterations for Asian patients. This study aimed to profile genomic alterations of SBA in Japanese patients using targeted next-generation sequencing (NGS). METHODS: We examined 22 surgical resections from patients with primary SBA. SBA genomic alterations were analyzed by NGS. Mismatch repair (MMR) status was determined by immunohistochemical analysis. Mucin phenotypes were classified as gastric (G), intestinal (I), gastrointestinal (GI), and null (N) types on MUC2, MUC5AC, MUC6, and CD10 immunostaining. RESULTS: The most common genomic alterations found in SBA tumors were TP53 (n = 16), followed by KRAS (n = 6), APC (n = 5), PIK3CA (n = 4), CTNNB1 (n = 3), KIT (n = 2), BRAF (n = 2), CDKN2A (n = 2), and PTEN (n = 2). Deficient MMR tumors were observed in 6 out of 22 patients. Tumor mucin phenotypes included 2 in G-type, 12 in I-type, 3 in GI-type, and 5 in N-type. APC and CTNNB1 mutations were not found in G-type and GI-type tumors. KRAS mutations were found in all tumor types except for G-type tumors. TP53 mutations were found in all tumor types. Although no single gene mutation was associated with overall survival (OS), we found that KRAS mutations were associated with significant worse OS in patients with proficient MMR tumors. CONCLUSIONS: SBA genomic alterations in Japanese patients do not differ significantly from those reports in Western countries. Tumor localization, mucin phenotype, and MMR status all appear to impact SBA gene mutations.

Clinicopathologic Characteristics and A20 Mutation in Primary Thyroid Lymphoma.

BACKGROUND: Primary thyroid lymphoma (PTL) is a rare disease frequently arising against a background of autoimmune thyroiditis. It has recently been reported that the inactivation of the NF-κB negative regulator A20 by deletion and/or mutation could be involved in the pathogenesis of subsets of B-cell lymphomas. This study investigated the clinicopathologic characteristics and A20 mutation in patients with PTL. METHODS: We analyzed the characteristics of 45 PTL patients (14 men and 31 women), with a median age of 71 (range, 35-90) years. A20 mutations were analyzed in DNA extracted from 20 samples consisting of 19 tumor tissue samples and 1 sample from Hashimoto's thyroiditis. RESULTS: Thirty-five patients (82%) had a history of Hashimoto's thyroiditis, and 29 (64%) had diffuse large B-cell lymphoma (DLBCL) and presented with larger tumors including bulky mass, elevated soluble interleukin-2 receptor levels, and a longer history of Hashimoto's thyroiditis than that of patients with mucosa-associated lymphoid tissue (MALT) lymphoma (n=16). A20 mutations were identified in 3 of 19 PTL patients (16%), in 2 of the 10 (20%) with DLBCL and in 1 of the 9 (11%) with MALT lymphoma. Interestingly, all patients with A20 mutations had Hashimoto's thyroiditis. Furthermore, they had a common missense variant in exon 3 (rs2230926 380T>G; F127C), which reduces the ability of A20 to inhibit NF-κB signaling. CONCLUSION: Our study suggests that the histological features of PTL affect clinical outcomes and that A20 mutations are related to PTL pathogenesis in some patients with Hashimoto's thyroiditis.

Novel Method of Sampling the Gastrointestinal Muscle Layer: Feasibility of Endoscopic Muscular Resection with a Ligation Device in an in Vivo Porcine Model.

BACKGROUND: Gastrointestinal muscular sampling is useful in the histological assessment of functional gastrointestinal disorders. We devised a new sampling method to obtain a large volume of muscle tissues and then investigated the feasibility and safety of endoscopic muscular resection with a ligation device in an in vivo porcine model. METHODS: After establishing a submucosal tunnel, a rubber band was placed on the muscle tissue by sucking the exposed muscle layer. Thereafter, the established pseudopolyp was removed using an electrocautery snare, and the entry site of the submucosal tunnel was closed endoscopically. This procedure was performed at three sites in the esophagus and stomach of two pigs. The technical success, histology, and survival rate on postoperative day 7 were examined postoperatively. RESULTS: We successfully completed the mentioned procedure in 11 of the 12 sites (92%), without the occurrence of severe adverse events. The median diameters of obtained tissues from the esophagus and stomach, respectively, were 5 mm and 10 mm. Histologically, both the inner and outer muscle layers were included in all specimens. The postprocedural course was found uneventful in both pigs during the observatory period. CONCLUSIONS: Endoscopic muscular resection using a ligation device enabled us to obtain large and thick muscle tissue samples. This approach may facilitate more precise histological assessments of functional gastrointestinal disorders.

Three-dimensional visualization improves the endoscopic diagnosis of superficial gastric neoplasia.

BACKGROUND: Three-dimensional (3D) technology has been used in many fields, including flexible endoscopy. We evaluated the usefulness of 3D visualization for endoscopically diagnosing superficial gastric neoplasia. METHODS: Twelve participants (4 novices, 4 trainees and 4 experts) evaluated two-dimensional (2D) and 3D endoscopic still images of 28 gastric neoplasias, obtained before ESD with white-light imaging (WLI) and narrow-band imaging (NBI). Assessments of the delineation accuracy of tumor extent and tumor morphology under 2D and 3D visualization were based on the histopathological diagnosis of ESD specimens. Participants answered visual analog scale (VAS) questionnaires (0-10, worst to best) concerning the (a) ease of recognition of lesion morphology, (b) lesion extent and (c) comprehensive endoscopic cognition under 2D and 3D visualization. The endpoints were the accuracy of tumor extent and morphology type and the degree of confidence in assessing (a)-(c). RESULTS: The delineation accuracy of lesion extent [mean (95% confidence interval)] with WLI under 3D visualization [60.2% (56.1-64.3%)] was significantly higher than that under 2D visualization [52.3% (48.2-56.4%)] (P < 0.001). The accuracy with NBI under 3D visualization [70.3% (66.8-73.7%)] was also significantly higher than that under 2D visualization [64.2% (60.7-67.4%)] (P < 0.001). The accuracy of the morphology type with NBI under 3D visualization was significantly higher than that under 2D visualization (P = 0.004). The VAS for all aspects of endoscopic recognition under 3D visualization was significantly better than that under 2D visualization (P < 0.01). CONCLUSIONS: Three-dimensional visualization can enhance the diagnostic quality for superficial gastric tumors.

Relationship between gastroesophageal reflux disease (GERD) and constipation: laxative use is common in GERD patients.

BACKGROUND: The relationship between gastroesophageal reflux disease (GERD) and constipation has not yet been examined in Japan. We herein analyzed the use of laxatives by GERD and non-GERD patients to clarify the relationship between GERD and constipation. METHODS: This was a retrospective observational study designed to examine the use of laxatives by GERD and non-GERD patients. A total of 118 patients (mean age 69.7 years, 50 males) with reflux esophagitis (RE) and non-erosive reflux disease (NERD) who received maintenance acid-suppressive therapy for more than 1 year were included in the GERD group (83 RE patients, 35NERD patients). Similarly, 61 patients (mean age 69.4 years, 28 males) who received regular acid-suppressive therapy for reasons other than GERD were included in the non-GERD group. We also investigated demographic factors associated with the onset of GERD, including body mass index (BMI), age, and sex. RESULTS: The frequency of laxative use was significantly higher in the GERD group (38.1%) than in the non-GERD group (21.3%). No significant differences were observed in dose frequencies between the groups. The type of laxative used also did not significantly differ between the groups. Furthermore, no significant differences were noted in sex, age, or BMI between the groups. CONCLUSIONS: The use of laxatives was significantly more common in GERD patients than in non-GERD patients. The present results suggest that a relationship exists between GERD and constipation.

Three-dimensional flexible endoscopy enables more accurate endoscopic recognition and endoscopic submucosal dissection marking for superficial gastric neoplasia: a pilot study to compare two- and three-dimensional imaging.

BACKGROUND: Three-dimensional (3D) visualization offers better depth recognition than two-dimensional (2D) imaging, thus helping to provide more useful information. We compared 3D and 2D endoscopy with regard to endoscopic recognition and endoscopic submucosal dissection (ESD) marking for superficial gastric neoplasia. METHODS: ESD marking was performed on half of a neoplasia margin under 2D observation and the on other half under 3D observation for 28 gastric lesions (26 early gastric cancers and 2 adenomas). The accuracy of ESD marking was evaluated based on the distance between the pathological and endoscopic neoplasia margins measured on histology sections of ESD specimens. The technical ease of ESD marking and endoscopic lesion recognition (lesion morphology, lesion extent, and comprehensive endoscopic cognition) were assessed using visual analog scale (VAS) questionnaires. RESULTS: The mean distance between the pathological and endoscopic margins under 3D observation (1.03 ± 0.80 mm) was significantly (p = 0.002) shorter than that under 2D observation (1.94 ± 1.96 mm). The VAS for technical ease of ESD marking under 3D observation was significantly better (p < 0.01) than that under 2D observation. The VAS for all aspects of endoscopic recognition under 3D observation was significantly better (p < 0.01) than under 2D observation. CONCLUSIONS: 3D flexible endoscopy achieved more accurate endoscopic recognition and ESD marking for superficial gastric neoplasia than a 2D approach in a clinical setting of ESD.

Influence of hypergastrinemia secondary to long-term proton pump inhibitor treatment on ECL cell tumorigenesis in human gastric mucosa.

Proton pump inhibitor (PPI) therapy causes hypergastrinemia, which could promote the development and progression of neuroendocrine tumors (NETs). Concerns have been raised about the safety of long-term PPI use due to a possible increased risk of NETs. This study aimed to investigate the association between hypergastrinemia and the risk of NETs. Twenty outpatients presenting with serum gastrin levels greater than 400 pg/mL after long-term PPI treatment were registered in this study. Immunohistochemical analyses for chromogranin A (CgA), Ki67, gastrin and CCK/B gastrin receptor (CCKBR) were performed, and positive cell numbers were counted. There were no NET or gastric epithelial neoplasia cases observed among any of the 20 patients examined throughout the PPI treatment period. Histologically, ECL cell hyperplasia were shown in all patients. However, no relationship was found between serum gastrin levels and the number of CgA positive ECL cells. There was also no relationship between serum gastrin levels and the proportion of Ki67 positive cells or the density of CCKBR positive cells. The data indicate no relationship may exist between NETs and hypergastrinemia secondary to PPI treatment in patients having no, or mild, atrophic gastritis.

Feasibility and safety of third-space endoscopic full-thickness resection in ex vivo and in vivo porcine models.

Background and study aims Endoscopic full-thickness resection (EFTR) involves several technical issues that need to be addressed. We devised a novel technique termed third-space EFTR and investigated its feasibility and safety in animal models. Methods Third-space EFTR was performed in three isolated porcine stomachs (ex vivo) and four live pigs (in vivo, 1-week survival). The technique involved a circumferential mucosal incision, submucosal tunnelling on the proximal side, endoscopic suturing of the surrounding mucosa, a circumferential seromuscular incision in the submucosal tunnel, transoral retrieval and entry site closure of the tunnel. The technical outcomes were investigated. Results In the ex vivo study, the procedure was successfully completed with R0 resection. In the in vivo study, the procedure was completed in all pigs; however, R0 resection failed in one pig owing to snaring resection. All pigs survived without severe adverse events. Conclusions Our findings indicate that third-space EFTR is feasible and safe. This technique may be useful as a minimally invasive endoscopic option for reliable treatment of small gastric submucosal tumours.

Comparison of clinical symptoms, gastric motility and fat intake in the early chronic pancreatitis patients with anti-acid therapy-resistant functional dyspepsia patients.

BACKGROUND: There was no available data concerning the clinical differentiation between the updated definition of early chronic pancreatitis (ECP) and anti-acid therapy-resistant functional dyspepsia (RFD). AIMS: We aimed to determine whether clinical symptoms, gastric motility, psychogenic factors and fat intake can help distinguish early chronic pancreatitis (ECP) from anti-acid therapy-resistant functional dyspepsia patients with pancreatic enzyme abnormalities (RFD-P) and anti-acid therapy-resistant functional dyspepsia (RFD) patients using endosonography. METHODS: We enrolled 102 consecutive patients presenting with typical symptoms of RFD patients (n = 52), ECP patients (n = 25) and RFD-P patients (n = 25). ECP patients were diagnosed based on the criteria recommended by the Japan Pancreatic Association. Gastric motility was evaluated by 13C-acetate breath tests. Severity of duodenal inflammation was examined. RESULTS: 24.5% of RFD patients were determined as ECP using endosonography. Abdominal pain score in Gastrointestinal Symptom Rating Scale (GSRS) in the patients with ECP was significantly lower compared to that in the patients with RFD-P. There were no significant differences in State-Trait Inventory (STAI)-state/-trait scores, Self-Rating Questionnaire for Depression (SRQ-D) scores and clinical symptoms for fat intake among three groups. The early phase of gastric emptying (AUC5; AUC15) in ECP and RFD-P patients were significantly disturbed compared to those in RFD patients. CONCLUSIONS: Evaluation of severity of abdominal pain and measurement of the early phase of gastric emptying will be useful tools to distinguish ECP patients from RFD patients. Accurate diagnosis of ECP patients may contribute to the prevention from advancing of chronic pancreatitis.

Impact of Cyclooxygenase-2 1195 G-Carrier Genotype Associated with Intestinal Metaplasia and Endoscopic Findings Based on Kyoto Classification.

BACKGROUND/AIMS: We aimed to clarify whether cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) genotypes were associated with certain histological findings and endoscopical appearances based on Kyoto classification. METHODS: We enrolled 285 Helicobacter pylori-infected gastritis patients. Genotypes of COX-2 1195, COX-2 1290, mPGES-1, interleukin-1ß (IL-1ß) 511 and tumour necrosis factor-α (TNF-α) 308 were analyzed. Genotyping was performed by polymerase chain reaction. Endoscopic appearances and histological assessment were determined by using Kyoto classification, operative link on gastritic intestinal metaplasia assessment and the updated Sydney system. RESULTS: There was a significant (p = 0.027) relationship between the IL-1ß 511 C-carrier and histological gastric inflammation in H. pylori-infected gastritis patients. There was a significant (p = 0.009) correlation between the COX-2 1195 G-carrier genotype and histological intestinal metaplasia in the gastric antrum of H. pylori-infected gastritis patients and gastric xanthoma (p = 0.027). The COX-2 1195 G-carrier genotype was also significantly (p = 0.038) associated with the score of endoscopic intestinal metaplasia based on Kyoto classification. The mPGES-1 genotype was significantly (p = 0.002) associated with endoscopic swelling of area. CONCLUSION: Our results suggest that in Japan, there exists a significant correlation between the COX-2 1195 G-carrier genotype and intestinal metaplasia in histological and endoscopic findings based on Kyoto classification in H. pylori-infected gastric mucosa.

Utility of KRAS mutation detection using circulating cell-free DNA from patients with colorectal cancer.

In this study, we evaluated the clinical utility of detecting KRAS mutations in circulating cell-free (ccf)DNA of metastatic colorectal cancer patients. We prospectively recruited 94 metastatic colorectal cancer patients. Circulating cell-free DNA was extracted from plasma samples and analyzed for the presence of seven KRAS point mutations. Using the Invader Plus assay with peptide nucleic acid clamping method and digital PCR, KRAS mutations were detected in the ccfDNA in 35 of 39 patients previously determined to have primary tumors containing KRAS mutations using the Luminex method, and in 5 of 55 patients with tumors containing wild-type KRAS. Curative resection was undertaken in 7 of 34 patients with primary and ccfDNA KRAS mutations, resulting in the disappearance of the mutation from the cell-free DNA in five of seven patients. Three of these patients had tumor recurrence and KRAS mutations in their ccfDNA reappeared. Epidermal growth factor receptor blockade was administered to 24 of the KRAS tumor wild-type patients. Of the 24 patients with wild-type KRAS in their primary tumors, three patients had KRAS mutations in their ccfDNA and did not respond to treatment with epidermal growth factor receptor (EGFR) blockade. We also detected a new KRAS mutation in five patients during chemotherapy with EGFR blockade, before disease progression was detectable with imaging. The detection of KRAS mutations in ccfDNA is an attractive approach for predicting both treatment response and acquired resistance to EGFR blockade, and for detecting disease recurrence.

Retrieval of Retained Capsule Endoscopy at Small Bowel Stricture by Double-Balloon Endoscopy Significantly Decreases Surgical Treatment.

GOALS: The aim is to elucidate the efficacy and safety of double-balloon endoscopy (DBE) for small bowel capsule endoscopy (SBCE) retrieval from small bowel stricture and to follow the outcome of the stricture where the SBCE was entrapped. BACKGROUND: The retention of SBCE is a serious adverse event and most retained capsules are retrieved by surgery. There is still no report analyzing the follow-up of patients with stricture after retrieval of entrapped SBCEs by DBE. METHODS: This study was designed a retrospective cohort study. Subjects were 12 consecutive patients with small bowel stricture where retrieval of entrapped SBCE was attempted using DBE. Success rate of the SBCE retrieval by DBE, surgical rate of the small bowel stricture, adverse events of DBE, and outcomes in the follow-up period were evaluated. RESULTS: Diagnoses were Crohn's disease, nonsteroidal anti-inflammatory drugs-induced enteropathy, ischemic enteritis, and carcinoma in 8, 2, 1, and 1 patients, respectively. SBCE was successfully retrieved in 11 of the 12 patients (92%). No adverse events were encountered in all endoscopic procedures such as retrieval of SBCEs and dilation of the strictures. Nine of the 12 patients (75%) did not undergo surgical treatment for the stricture where SBCE was entrapped through the follow-up period (mean, 1675±847 d). CONCLUSIONS: Retrieval of SBCEs using DBE was safe, had a high success rate, and was useful to evaluate the need for surgery. Seventy-five percent of patients with small bowel stricture where the SBCE was entrapped did not require surgery through approximately 5 years.

Omeprazole increased small intestinal mucosal injury in two of six disease-free cases evaluated by capsule endoscopy.

Recently, a report showed that proton-pump inhibitors (PPI) exacerbate non-steroidal anti-inflammatory drug-induced small intestinal injury in the rat. In the present report of two human cases, small intestinal injuries were probably induced and/or exacerbated after PPI treatment. Case 1 was a 30-year-old healthy man in whom no small intestinal mucosal break was detected at baseline capsule endoscopy. After 2 weeks of omeprazole given 20 mg once daily, he was found to have two small intestinal mucosal breaks. Case 2 was a 40-year-old healthy man in whom six small intestinal mucosal breaks were detected at baseline capsule endoscopy. After 2 weeks of omeprazole given 20 mg once daily, 12 small intestinal mucosal breaks were detected. Follow-up capsule endoscopy carried out 3 weeks after stopping omeprazole in case 2 showed seven small intestinal mucosal breaks were detected, showing restitution of the small intestinalmucosal injury. These two cases were obtained from a pilot study evaluating the effect of single administration of PPI on small intestinal mucosa in humans. In the pilot study, six healthy male volunteers were given omeprazole 20 mg for a period of 2 weeks. Small intestinal injury was evaluated before and after PPI treatment using capsule endoscopy. In four subjects other than the two above-mentioned cases, no small intestinal mucosal breaks were found at both baseline and post-treatment capsule endoscopy. Considering the two cases with increased or newly detected small intestinal mucosal breaks, omeprazole may exacerbate/induce small intestinal injury.

Localization of phosphorylated ErbB1-4 and heregulin in colorectal cancer.

BACKGROUND: The ErbB family consists of four proteins including (EGFR)/ErbB1, ErbB2, ErbB3, and ErbB4, and plays a crucial role in the promotion of multiple tumorigenic processes. In addition to the traditional pathways of EGFR signaling, EGFR translocates to the nucleus and acts as a transcription factor in the proliferation of cancer cells. Heregulin is known as both an ErbB3 and an ErbB4 ligand. This study aimed to investigate the expression of heregulin and its relevant EGFR family members as well as their phosphorylated forms in human colorectal cancer (CRC) tissues and to determine the relationship between their expression and clinicopathological factors including patient prognosis. METHODS: We analyzed the effects of exogenous heregulin on ErbB2, ErbB3 and ErbB4 phosphorylation in Caco-2, DLD-1, and HCT 116 colon cancer cell lines by western blot analysis. We examined 155 surgical resections from colorectomy patients. Cellular localization of ErbB1-4, their phosphorylated forms and heregulin protein was analyzed in CRC surgical resections by immunohistochemical analysis. Immunohistochemical results were compared with clinicopathological factors and patient prognosis. RESULTS: Phosphorylated ErbB2 (pErbB2) and phosphorylated ErbB3 (pErbB3) were detected in both nuclear and cytosolic fractions of Caco-2 and DLD-1 cells stimulated by exogenous heregulin. Whereas, phosphorylated ErbB4 (pErbB4) was detected only in cytosolic fractions of HCT 116 cells stimulated by exogenous heregulin. Phosphorylated EGFR (pEGFR) immunoreactivity was observed in the cytoplasm and nuclei of cancer cells, whereas the pattern of EGFR staining was membranous and cytoplasmic. Subcellular localization of pErbB2, cytoplasmic, membranous, or nuclear, varied among cases. pErbB3 immunoreactivity was exclusively observed in the nuclei of cancer cells. pErbB4 immunoreactivity was observed in the cell membrane of cancer cells. Statistically, heregulin immunoreactivity correlated with pErbB2 and pErbB4 expression. In multivariate analysis for disease free survival, lymph node status, pErbB3 and pErbB4 expression retained independent prognostic significance. In multivariate analysis for overall survival, lymph node status, pEGFR and pErbB4 retained independent prognostic significance. CONCLUSIONS: ErbB2 and ErbB3 phosphorylated by heregulin localized in the nucleus of CRC cells. Phosphorylated ErbB1-4 and heregulin contribute to poorer patient prognosis in CRC. This heregulin-ErbB family member autocrine loop may be a candidate for targeted treatment of CRC.

Apurinic/apyrimidinic endonuclease-1 is associated with angiogenesis and VEGF production via upregulation of COX-2 expression in esophageal cancer tissues.

Apurinic/apyrimidinic endonuclease-1 (APE-1) is a key enzyme responsible for DNA base excision repair and is also a multifunctional protein such as redox effector for several transcriptional factors. Our study was designed to investigate APE-1 expression and to study its interaction with cyclooxygenase (COX)-2 expression and VEGF production in the esophageal cancer. The expression of APE-1, COX-2, monocyte chemoattractant protein (MCP)-1, CC-chemokine receptor (CCR)2, and VEGF were evaluated by immunohistochemistry in 65 human esophageal squamous cell carcinoma (ESCC) tissues. Real-time PCR and Western blotting were performed to detect mRNA and protein expression of APE-1 and p-signal transducer and activator of transcription 3 (STAT3) expression in MCP-1-stimulated ESCC cell lines (KYSE 220 and EC-GI-10). siRNA for APE-1 was treated to determine the role of APE-1 in the regulation of COX-2 expression, VEGF production, and antiapoptotic effect against cisplatin. In human ESCC tissues, nuclear localization of APE-1 was observed in 92.3% (60/65) of all tissues. There was a significant relationship (P = 0.029, R = 0.49) between nuclear APE-1 and cytoplasmic COX-2 expression levels in the esophageal cancer tissues. In KYSE 220 and EC-GI-10 cells, MCP-1 stimulation significantly increased mRNA and protein expression of APE-1. Treatment with siRNA for APE-1 significantly inhibited p-STAT3 expression levels in MCP-1-stimulated cells. Furthermore, treatment of siRNA for APE-1 significantly reduced COX-2 expression and VEGF production in MCP-1-stimulated esophageal cancer cell lines. Treatment with APE-1 siRNA significantly increased apoptotic levels in cisplatin-incubated KYSE 220 and EC-GI-10 cells. We concluded that APE-1 is overexpressed and associated with COX-2 expression and VEGF production in esophageal cancer tissues.

Micropapillary pattern at the invasive front and its association with unresectable colorectal carcinomas.

Unresectable colorectal carcinomas (CRCs) as considered incurable even if the primary tumors and the metastatic ones can undergo resection are correlated with poor prognosis. We evaluated the association between micropapillary pattern at the invasive front and unresectable CRCs. Thirty-four out of 264 (12.9%) CRC patients with stages III and IV were unresectable cases. The patients with unresectable CRCs had significantly worse survival than those with resectable CRCs (P < 0.001). Micropapillary pattern was evident in 12 (4.5%) out of 264 cases. This pattern was observed in 6 of 34 (17.6%) unresectable CRCs and in 6 of 230 (2.6%) resectable cases (P = 0.002). Unresectable CRCs revealed more frequently deeper invasion (odds ratio (OR), 1.175; 95% confidence interval (CI), 1.113-1.241), lymph node metastasis (OR, 2.356; 95% CI, 1.132-4.905), and presence of micropapillary pattern at the invasive front (OR, 8.000; 95% CI, 2.415-26.504) as compared to resectable cases. By multivariable logistic regression analysis, only micropapillary pattern was shown to be an independent predictor of unresectable CRCs (OR, 9.451; 95% CI, 2.468-36.196; P < 0.001). In conclusion, micropapillary pattern at the invasive front is associated with unresectable CRCs, and detection of it could help identify unresectable CRC cases.