Prognostic factors to predict the survival in patients with advanced gastric cancer who receive later-line nivolumab monotherapy-The Asahikawa Gastric Cancer Cohort Study (AGCC).

BACKGROUND: Chemotherapy for advanced gastric cancer is recommended in the guidelines; however, later-line treatment remains controversial. Since immune checkpoint inhibitors have been used for the treatment of various malignancies, trials have been performed for gastric cancer. A phase 3 trial indicated the survival benefit of nivolumab monotherapy for gastric cancer patients treated with prior chemotherapy regimens. PATIENTS AND METHODS: A regional cohort study was undertaken to determine the real-world data of nivolumab treatment for patients with advanced or recurrent gastric cancer. The patients were enrolled for 2 years from October 2017 to October 2019 and were prospectively followed for 1 year to examine the overall survival (OS). The patient characteristics were analyzed in a multivariate analysis and a nomogram to predict the probability of survival was generated. RESULTS: In total, 70 patients who received nivolumab as ≥third-line chemotherapy were included in the Asahikawa Gastric Cancer Cohort. The median OS was 7.5 (95% CI, 4.8-10.2) months and the response rate was 18.6%. Diffuse type classification, bone metastasis, high neutrophil/lymphocyte ratio, and high CRP were associated with poor OS/prognosis in the multivariate analysis. A nomogram was developed based on these clinical parameters and the concordance index was 0.80 (95% CI, 0.68-0.91). The responders were aged and were frequently diagnosed with intestinal type gastric cancer, including patients with a HER2-positive status (27.3%) or microsatellite instability-high (27.3%) status. CONCLUSIONS: The regional cohort study of nivolumab monotherapy for gastric cancer patients revealed prognostic factors and a nomogram was developed that could predict the probability of survival.

Safety and efficacy of cold snare polypectomy for small colorectal polyps: A prospective randomized control trial and one-year follow-up study.

TRIAL DESIGN: Elimination of small colorectal polyps with cold snare polypectomy (CSP) is reported to be as safe as hot snare polypectomy (HSP). The effectiveness of CSP has not been clearly defined, and the incidence of long-term recurrence has not been determined. We conducted a randomized control study and one-year follow-up study to assess their safety and efficacy. METHODS: Patients with small colorectal polyps were randomized to receive CSP or HSP. Polypectomy was performed to determine the pathological curability, and patients completed a questionnaire about the tolerability of the procedure. Follow-up colonoscopy was performed to determine the local recurrence of adenoma. The major outcome was the non-inferiority of CSP to HSP in the rate of delayed bleeding and minor outcomes, including the incidence of immediate bleeding and perforation, procedural time, and the resection rate. RESULTS: A total of 119 participants were recruited in this randomized study and underwent polypectomy. Among the 458 polyps, 332 eligible polyps were analyzed. The rate of adverse events was 0.6% (1/175) for CSP and 0% (0/157) for HSP, which showed the non-inferiority of CSP. While the complete resection rate of CSP was very high (100%), the R0 rate was not satisfactory (horizontal margin, 65.5%; vertical margin, 89.1%). Two local recurrences (2.5%) were observed in the follow-up of 80 adenomas treated with CSP. No recurrence was found in 79 lesions in the HSP group, which was not significant (P = .06). CONCLUSIONS: Colorectal polyps were safely resected using CSP, similar to HSP. Most would agree to say that CSP is considered safer than HSP. The main question is then related to efficacy. Our results of the present study demonstrate that recurrence after CSP should be carefully managed for curative treatment.

Rare case of fecal impaction caused by a fecalith originating in a large colonic diverticulum: A case report.

BACKGROUND: Fecal impaction is defined as a large mass of compacted feces in the colon and has the potential to induce a serious medical condition in elderly individuals. Fecal impaction is generally preventable, and early recognition of the typical radiological findings is important for making an early diagnosis. The factors that lead to fecal impaction are usually similar to those causing constipation. Few cases with fecal impaction associated with a diverticulum have been reported. CASE SUMMARY: We present the case of a 62-year-old woman who suffered from abdominal pain and vomiting, had a medical history of repeated acute abdomen and was diagnosed with fecal impaction in the descending colon based on X-ray and computed tomography (CT) imaging. After examination by gastrografin-enhanced colonography following colonoscopy and CT colonography, the fecalith was suspected to have been produced at the site of a large diverticulum in the transverse colon. The fecalith was surgically resected, and a histological diagnosis of pseudodiverticulum was made. There was no recurrence during 33 mo of follow-up. CONCLUSION: This case highlights the importance of accurate identification and treatment of a fecal impaction. This case indicated that the endoscopic evacuation and subsequent colonography were effective for identifying a diverticulum that might have caused fecal impaction. A fecal impaction was associated with the diverticulum. Consequently, the planned diverticulectomy was performed. Appropriate emergency medical treatment and maintenance treatments should be selected in such cases to prevent recurrence.

White coat status is a predictive marker for post-esophageal endoscopic submucosal dissection stricture: a retrospective study.

BACKGROUND: Steroid therapy is primarily used to prevent esophageal stricture after endoscopic submucosal dissection (ESD). However, esophageal stricture can still occur after preventive therapy, and the effect of preventive steroid therapy cannot be predicted before stricture formation. This study aimed to clarify the risk factors for esophageal stricture after preventive steroid therapy. METHODS: This was a retrospective study conducted at three institutions. From January 2011 to February 2018, 28 large-sized SENs in 26 patients who had a mucosal defect that involved more than three-quarters of the esophageal circumference were enrolled. We classified white coats on artificial ulcers after esophageal ESD into three groups (thin, moderately thick, thick) based on endoscopic images obtained on postoperative day 7. RESULTS: The white coat status on the artificial ulcer after ESD was a significant risk factor for post-ESD stricture (p < 0.05). The stricture rates in patients with thin, moderately thick and thick white coats were 10.0, 36.4 and 85.7%, respectively. When thin and moderately thick white coats were combined, the stricture rate was 23.8%. The rate of stricture in lesions with thick white coats was significantly higher than that in patients with thin white coats or thin to moderately thick white coats (p < 0.05). The multivariate analysis revealed that the white coat status was an independent factor related to esophageal stricture (odds ratio 13.70, 95% confidence interval 1.22-154.0; p = 0.034). CONCLUSIONS: The thickness of the white coat is a useful marker for predicting the risk of post-ESD stricture and the effectiveness of preventive steroid therapy.

Efficacy of Vonoprazan-Based Triple Therapy for Helicobacter pylori Eradication: A Multicenter Study and a Review of the Literature.

BACKGROUND: Eradication therapies for Helicobacter pylori infection are advancing as new acid inhibitory reagents approved. The aim of this study was to assess the efficacy and safety of vonoprazan-based triple treatment. MATERIALS AND METHODS: Triple therapy with vonoprazan and two antibiotics (amoxicillin and clarithromycin or metronidazole) received focus in this analysis. We performed a multicenter retrospective study of patients who received vonoprazan-based eradication therapy between February 2015 and February 2016 and conducted a review of the literature. RESULTS: The eradication rate among the 799 patients in our multicenter study was 94.4% (95% confidence interval [CI] 92.6-96.2%) in the per-protocol analysis for first-line treatment (with vonoprazan 20 mg, amoxicillin 750 mg, and clarithromycin 200 or 400 mg, twice a day for 7 days) and 97.1% (95% CI 93.0-101.1%) for second-line treatment (with vonoprazan 20 mg, amoxicillin 750 mg, and metronidazole 250 mg, twice a day for 7 days). The overall incidence of adverse events was 4.4% in an intention-to-treat analysis with no patients hospitalized. In a literature review, six reports, in which 1380 patients received vonoprazan-based first-line eradication therapy, were included and were all reported by Japanese researchers. The eradication success rates in per-protocol analysis were between 85 and 93%, which was roughly the same among the studies. CONCLUSIONS: Vonoprazan-based triple therapy was effective and safe for Helicobacter pylori eradication in real-world experience, confirmed by a multicenter study and a review of the pertinent literature.

Endoscopic Submucosal Dissection for Depressed-type Early Adenocarcinoma of the Terminal Ileum.

We herein report a rare case of ileal adenocarcinoma that was completely removed by endoscopic submucosal dissection (ESD) without any complications. An 80-year-old man was referred to our hospital to undergo treatment for an ileal tumor. Conventional colonoscopy showed a reddish depressed lesion that was classified as type 0-IIc according to the Paris classification. The ileal tumor was successfully removed en bloc by ESD with a negative surgical margin. The histological findings showed a well-differentiated adenocarcinoma with no submucosal or lymphovascular invasion. Colonoscopy and CT performed one year after ESD showed no local recurrence, stenosis, or lymph node metastasis.

Infection with fully mature Corynosoma cf. validum causes ulcers in the human small intestine.

Corynosoma is a parasite that can normally be found in the intestinal tract of fish-eating mammals, particularly in seals and birds. The present case proposed that Corynosoma could attain full maturity in the human intestine. A 70-year-old female complained of abdominal pain. A computed tomography (CT) scan revealed a swelling of the intraperitoneal lymph nodes with no responsible lesion. Video capsule endoscopy and double-balloon endoscopy detected several ulcerations and one parasite in the ileum, which was tightly attached at the bottom of the ulcerations. The parasite was cylindrical and measured approximately 10 mm (long) x 3 mm (wide). Pathologically, the worm had a four-layered body wall and contained embryonated eggs. The sequences of the parasite-derived nuclear ribosomal DNA fragment and mitochondrial DNA fragment of cox1 were almost identical to those of Corynosoma validum. The patient's abdominal pain immediately improved after the administration of pyrantel pamoate (1,500 mg). Corynosoma was possibly the responsible disease in a patient who complained of abdominal pain and in whom no responsible lesion was detected by CT, gastroduodenoscopy or colonoscopy. Examinations of the small intestines should be aggressively performed in such cases.

[Pancreatic metastasis of malignant melanoma diagnosed by EUS-guided fine needle aspiration (EUS-FNA)].

Pancreatic metastasis of malignant melanoma is rarely diagnosed while the patient is alive. We report a case of metastatic melanoma of the pancreas in a 35-year-old woman presenting with a solid mass of the pancreas. Her past medical history included a radical hysterectomy 2 years previously for malignant melanoma of the vagina. Twelve months later, lung metastasis was also resected. EUS-guided fine needle aspiration (EUS-FNA) identified that the pancreatic tumor was histologically and immunohistochemically identical to the surgical specimen of her lung neoplasm. Imaging studies including US, CT, and MRI have limited value to distinguish the tumors from primary ductal adenocarcinoma. EUS-FNA can provide tissue diagnosis from pancreatic masses, specifically when other modalities have failed.

Regulation of DNA duplex formation by hypoxic irradiation: one-electron reduction characteristics of oligodeoxynucleotides possessing 2-oxoalkyl functional group.

We synthesized oligodeoxynucleotides (ODN) possessing 2-oxoalkyl group on thymidine (d(oxo)T) to characterize the radiolytic reduction in aqueous solution. Corresponding unmodified ODNs were generated from ODNs containing d(oxo)T upon hypoxic irradiation. Enzymatic digestion of the duplex consisting of the hypoxically irradiated ODN containing d(oxo)T and its complementary strand resulted in an efficient cleavage, but no cleavage was observed when a control duplex was digested without irradiation.