A gastric invasive tubular adenocarcinomatous lesion arising from foveolar-type neoplasia: molecular histogenesis.

Here, we report a rare case of a depressed lesion exhibiting both tubular differentiated adenocarcinomatous (TDA) and intraepithelial foveolar neoplasia (IFN) components (with the histological appearance of foveolar hyperplasia due to low-grade atypia). Histologically, the TDA surrounded the IFN, suggesting that the TDA may have originated from the IFN. Therefore, we examined molecular alterations in the TDA and IFN components separately. MUC5AC and MUC6 expression was observed immunohistochemically in both components. p53 expression was wild type in both components, suggesting no mutation of TP53. We investigated allelic imbalances at multiple loci (1p, 3p, 4p, 5q, 8q, 9p, 13q, TP53, 18q, and 22q), mutations (KRAS, BRAF, and GNAS), and DNA methylation and microsatellite status in both components using PCR-based analyses. Although multiple allelic imbalances were common to both components, allelic imbalances at 3p and TP53 were found only in the TDA component. No mutations were found, and DNA methylation status was low epigenotype for both components. Ultimately, this tumor was considered microsatellite stable. Considering the origin of TDA, which is frequently encountered in routine practice, IFN may develop into TDA.

Histopathological vertical margin positivity in cold snare polypectomy and mucosal resection for sessile serrated lesions.

BACKGROUND AND AIMS: Evidence regarding the status of the vertical margin of sessile serrated lesions (SSLs) resected using cold snare polypectomy (CSP) is lacking, and whether a histopathologically positive vertical margin is related to recurrence remains unclear. Therefore, this preliminary study aimed to clarify the rates of positive or unevaluable vertical and horizontal margins and the rate of muscularis mucosae resection in SSLs treated using CSP compared with those treated with endoscopic mucosal resection (EMR). METHODS: Histological outcomes of patients treated with CSP or EMR for SSL were evaluated in this single-center observational study. The primary outcome was the incidence of histopathologically positive vertical margins in CSP and EMR. Furthermore, the comparisons were adjusted for confounding factors using propensity score matching. RESULTS: Overall, 82 patients with SSLs were included in the CSP and EMR groups after matching. The incidence of positive histological vertical margins in the CSP and EMR groups were 67.1% and 2.4%, respectively (p<0.001). Regarding the evaluation of the presence of muscularis mucosae, 29.3% and 98.8% of the patients in the CSP and EMR groups, respectively, had a complete muscularis mucosae resection (p<0.001). CONCLUSIONS: A rigorous histopathologic evaluation revealed that for SSLs, CSP more frequently leads to positive vertical margins than EMR.

Delayed Perforation after Endoscopic Detachable Snare Ligation for Colonic Diverticular Hemorrhage.

A 74-year-old man was admitted to our hospital with severe hematochezia. Abdominal enhanced computed tomography (CT) demonstrated extravasation of contrast material from the descending colon. Colonoscopy revealed recent bleeding in the descending colon diverticulum. Bleeding was stopped using detachable snare ligation. Eight days later, the patient developed abdominalgia, and CT revealed free air caused by delayed perforation. The patient underwent emergency surgery. Perforation at the ligation site was detected using intraoperative colonoscopy. This report is the first to describe a case of delayed perforation after endoscopic detachable snare ligation for colonic diverticular hemorrhage.

Delayed Perforation of Colorectal Endoscopic Submucosal Dissection Treated by Endoscopic Ultrasound-Guided Drainage.

We report a case of a 70-year-old male with delayed perforation in the cecum treated by endoscopic ultrasonography-guided drainage for a pelvic abscess. The lesion was a 50-mm laterally spreading tumor, and endoscopic submucosal dissection (ESD) was performed. No perforation was detected during the operation, and en bloc resection was achieved. He had fever and abdominal pain on postoperative day (POD) 2. Computed tomography (CT) revealed the intra-abdominal free air, leading to a diagnosis of delayed perforation after ESD. Vital signs were stable, the perforation was considered minor, and endoscopic closure was attempted. The colonoscopy under fluoroscopy showed no perforation in the ulcer and no leakage of the contrast medium. He was managed conservatively with antibiotics and nothing per os. Symptoms improved; however, a follow-up CT on POD 13 revealed a 65-mm pelvic abscess, and endoscopic ultrasound (EUS)-guided drainage was successfully performed. The follow-up CT on POD 23 showed the reduction of abscess, and the drainage tubes were removed. Emergent surgical treatment is crucial in delayed perforation because it has a poor prognosis, and reports of conservative therapy for colonic ESD with delayed perforation are few. The present case was managed with antibiotics and EUS-guided drainage. Thus, EUS-guided drainage can be a treatment option for delayed perforation after colorectal ESD, if the abscess is localized.

Neuroendocrine tumor of the ampulla of Vater treated with endoscopic papillectomy: A case report.

We report the case of a 62-year-old female with a 6.3-mm low-grade neuroendocrine tumor of the ampulla of Vater, who underwent an endoscopic papillectomy. An endoscopic papillectomy was performed without complications. In the 26 months of follow-up, no local recurrence or metastasis occurred. Endoscopic treatment of ampullary neuroendocrine tumors is controversial. However, endoscopic papillectomy may be considered a treatment option if neuroendocrine tumors are small (<10 mm), have a low grade (G1), or do not have muscle layer or bile duct invasion.

Clinical Benefit of Polypectomy With Cutting Current for Colorectal Polyps: A Randomized Controlled Trial.

BACKGROUND/AIM: This study aimed to examine the effectiveness of polypectomy with cutting current (PCC) for colorectal polyps, compared with cold snare polypectomy (CSP). PATIENTS AND METHODS: The study design was a singlecenter randomized controlled trial. We included patients with one or more non-pedunculated colorectal polyps of 6 mm or more and less than 10 mm. The primary endpoint was the proportion of complete resection of the muscularis mucosae. RESULTS: Twenty-seven patients (37 polyps) were assigned to the CSP group, and 22 (29 polyps) were assigned to the PCC group. The number of polyps that could achieve complete muscularis mucosae resection was 7 (20.0%) in the CSP group and 24 (92.3%) in the PCC group, and the rate of complete muscularis mucosae resection was statistically significantly higher in the PCC group. CONCLUSION: PCC is a safer procedure because it can remove the muscularis mucosae more reliably.

[A case of rectum metastasis of breast cancer].

A 53-year-old woman visited the hospital of this study complaining of constipation. Colonoscopy revealed a circumferential tumor with severe stenosis, and a computed tomography scan showed neoplastic lesions in the rectum and right breast area. Histology was poorly differentiated adenocarcinoma, requiring differentiation between type 4 and metastatic rectal cancer. Additional immunohistochemical tests were performed and a rectal metastasis of breast cancer diagnosis was made. Hormonal therapy was effective and the tumor volume was significantly reduced. Rectal metastasis of breast cancer is said to be rare. However, in the case of patients diagnosed with breast cancer or with a history of breast cancer, considering the possibility of gastrointestinal metastasis using histopathological examination is important.

Clinical benefit of the multibending endoscope for gastric endoscopic submucosal dissection: a randomized controlled trial.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a technically difficult and time-consuming procedure. We aimed to investigate the efficacy and safety of ESD using a multibending endoscope to treat superficial gastrointestinal neoplasms. METHODS: Patients with a single early gastric cancer who met the absolute or expanded indications for ESD according to the Japanese gastric cancer treatment guidelines were enrolled and randomly assigned to undergo ESD using a conventional endoscope (C-ESD) or a multibending endoscope (M-ESD). Randomization was stratified by ESD operator experience and tumor location. The primary outcome was ESD procedure time, calculated as the time from the start of submucosal injection to complete removal of the tumor. RESULTS: 60 patients were analyzed (30 C-ESD, 30 M-ESD). The mean (standard deviation [SD]) ESD procedure times for M-ESD and C-ESD were 34.6 (SD 17.2) and 47.2 (SD 26.7) minutes, respectively (P = 0.03). Muscle layer damage occurred significantly less frequently with M-ESD (0.2 [SD 0.7] vs. 0.7 [SD 1.0]; P = 0.04). There were no significant differences between the two techniques in procedure time or damage to muscle layers for tumors located in the lower third of the stomach. CONCLUSIONS: ESD procedure time was significantly shorter with the multibending endoscope and fewer muscles were damaged. We recommend multibending endoscopy for ESD in the upper and middle thirds of the stomach to reduce procedure time and incidence of complications.

[A Case of Endoscopic Submucosal Dissection for Recurrent Gastric Cancer after Chemotherapy with Arterial Infusion].

The patient was a 90-year-old male. For early gastric cancer on the posterior wall of the upper gastric body, which is not indicated for endoscope treatment, chemotherapy with arterial infusion was carried out at other facilities at the request of the patient and his family. Thereafter, he suffered a relapse during follow-up, for which our hospital carried out endoscopic submucosal dissection(ESD). The outcome was a resection without cure. Taking into consideration his age and the fact that the scoring system for early gastric cancer with excised lesions without cure by ESD indicated a medium risk, we carried out no additional treatment but did conduct a follow-up. There has been no recurrence for 15 months following surgery. ESD does not provide evidence with regard to recurrence after other treatments. This patient had a scar following arterial infusion chemotherapy and a local injection solution was not infused into the submucosa right under the lesion. Although the treatment of exfoliation was difficult due to fibrosis of the submucosa, en-bloc resection was possible without any complications.