Preliminary Experience of Laparoscopic Cholecystectomy with Gallbladder Bed Dissection for Suspected Gallbladder Cancer

Selecting the appropriate operation for gallbladder cancer depends on the depth of cancer invasion, which remains difficult to determine preoperatively, especially with respect to the subserosal layer (pT2). We devised a laparoscopic cholecystectomy with gallbladder bed dissection (LC with GBD) as a new total biopsy method for suspected gallbladder cancer. We retrospectively reviewed the medical records of 19 patients who underwent LC with GBD to assess the usefulness of this procedure and the pathological findings. No severe morbidity or recurrence was encountered. LC with GBD could be performed easily and safely, and the patients’ postoperative course was almost equal to that of patients treated by conventional LC. Histologically, gallbladder cancer was diagnosed in five cases (pT1a, 3; pT2, 2). We believe that LC with GBD could play an important role in the potential treatment strategy for pT2 gallbladder cancer

New Surgical Procedure for Pancreas Head

In this study, we demonstrate two new methods for pancreaticoduodenectomy (PD). One method is the mini‐laparotomic PD by Shuriken‐shaped umbilicoplasty with the real‐time moving window‘s method. The other method is the new pancreaticojejunostomy (PJ) by punctured stent slide guiding method (PSSGM). This procedure could be performed by complete mini‐laparotomy under direct vision, and the final major wound is only 2 cm of round navel. PSSGM prevents the difference of caliber between pancreatic anastomosis and the inside out of jejunal mucosa in theory. Ten cases of mini‐lap PD were successfully performed under new PJ anastomosis. The pancreatic leakage (PL) was only one case of ISGPF grade A, and its frequency was 9% (1/11). Our mini‐lap PD by Shuriken‐shaped umbilicoplasty might be a useful way for overcoming the obstacles about safety, complication risk, cosmetic demand, and medical cost compared to laparoscopic PD. Also, our new device of PJ reconstruction by PSSGM might be an easy and useful device for the prevention of PL

Quality Assurance of Computer-Aided Detection and Diagnosis in Colonoscopy

Recent breakthroughs in artificial intelligence (AI), specifically via its emerging sub-field “Deep Learning,” have direct implications for computer-aided detection and diagnosis (CADe/CADx) for colonoscopy. AI is expected to have at least 2 major roles in colonoscopy practice; polyp detection (CADe) and polyp characterization (CADx). CADe has the potential to decrease polyp miss rate, contributing to improving adenoma detection, whereas CADx can improve the accuracy of colorectal polyp optical diagnosis, leading to reduction of unnecessary polypectomy of non-neoplastic lesions, potential implementation of a resect and discard paradigm, and proper application of advanced resection techniques. A growing number of medical-engineering researchers are developing both, CADe and CADx systems, some of which allow real-time recognition of polyps or in vivo identification of adenomas with over 90% accuracy. However, the quality of the developed AI systems as well as that of the study designs vary significantly, hence raising some concerns regarding the generalization of the proposed AI systems. Initial studies were conducted in an exploratory or retrospective fashion using stored images and likely overestimating the results. These drawbacks potentially hinder smooth implementation of this novel technology into colonoscopy practice. The aim of this article is to review both contributions and limitations in recent machine learning based CADe/CADx colonoscopy studies and propose some principles that should underlie system development and clinical testing

Usefulness of Background Coloration in Detection of Esophago-Pharyngeal Lesions Using NBI Magnification

Background and Aim. We evaluated the usefulness of background coloration (BC), a color change in the area between intrapapillary capillary loops (IPCLs) in the early esophago-pharyngeal lesions using NBI with magnificaiton. Methods. Between April 2004 and March 2010, a total of 294 esophago-pharyngeal lesions were examined using NBI with magnification, and the presence of BC and IPCL patterns were assessed. Using BC, discrimination of squamous cell carcinoma (SCC) or high-grade neoplasia (HGN) from low-grade neoplasia (LGN) or nonatypia was conducted. Results. Among 294 lesions, 209 lesions (71.1) were positive for BC, while 85 (28.9) were negative. In the BC-positive group, 187 lesions (89.5) were diagnosed as SCC/HGN. And 68 lesions (80.0) in the BC-negative group were diagnosed as LGN/nonatypia. Overall accuracy of BC to discriminate SCC/HGN from LGN/nonatypia was 87.3. The sensitivity and specificity were 91.9, 76.7. BC could discriminate SCC/HGN from LGN/nonatypia accurately (P 0.0001). Among 68 lesions classified into the IPCL type IV, the BC-positive group (n = 26) included 21 SCC/HGN lesions, while there were 36 LGN/nonatypia lesions in the 42 BC-negative lesions. Conclusions. BC is a useful finding in differentiating SCC/HGN from LGN/nonatypia lesions in the esophagus especially when it is combined with IPCL pattern classification

Endscopic Submucosal Dissection of a Heterotopic Gastric Mucosa in the Stomach: Report of a Case

A 38-year-old man with a submucosal tumor (SMT) at the anterior wall of the pylorus underwent upper gastrointestinal endoscopy. The tumor was 40 mm in diameter with a long stalk extending into the duodenal bulb. In addition, the long stalk had an ulcer with a blood vessel. Removal of this tumor was initially considered to be possible only by distal gastrectomy. However, endoscopic ultrasound (EUS) was subsequently proven to be a reliable investigative procedure for evaluating the lesion. The tumor was characterized by its origin in the second layer, and endoscopic submucosal dissection (ESD) was performed. En bloc resection of a 32 × 20 × 40 mm area of tissue with tumor-free lateral/vertical margins was accomplished without complication. Histopathological examination confirmed a heterotopic gastric mucosa. By immunostaining, the neoplasm was positive for MUC6 and negative for amylase and trypsin. In this case, EUS was used to investigate a heterotopic gastric mucosa that originated in the second layer, with no infiltration of the fourth layer under the tumor. Therefore, we performed successful ESD at the appropriate layer

Clinical Efficacy of Endocytoscopy for Gastrointestinal Endoscopy

Endocytoscopy (EC) is a contact-type optical endoscope that allows in vivo cellular observation during gastrointestinal endoscopy and is now commercially available not only in Japan but also in Asian, European Union, and Middle Eastern countries. EC helps conduct a highly accurate pathological prediction without biopsy. Initially, EC was reported to be effective for esophageal diseases. Subsequently, its efficacy for stomach and colorectal diseases has been reported. In this narrative review, we searched for clinical studies that investigated the efficacy of EC. EC seems to accurately diagnose gastrointestinal diseases without biopsy. Most of the studies aimed to clarify the relationship between endocytoscopic findings of gastrointestinal neoplasia and pathological diagnosis. Some studies have investigated non-epithelial lesions or diseases, such as inflammatory bowel disease or infectious diseases. However, there are few high-level pieces of evidence, such as randomized trials; thus, further studies are needed

Comparison of Surgeon Stress and Workload between Reduced-port and Laparoscopic Cholecystectomy : A Prospective Study

Single-port laparoscopic surgery（SPLS）has attracted attention in the field of minimally invasive surgery; however, the associated technical difficulty has delayed its adoption by all surgeons. Reduced-port laparoscopic surgery might be easier to perform than SPLS, and in this prospective study, we compared surgeon stress and workload between reduced-port laparoscopic cholecystectomy（RPLC）and conventional laparoscopic cholecystectomy（CLC）. Twenty consecutive patients were assigned to undergo either RPLC or CLC between July 2016 and April 2017. Two surgeons performed the operations. The differences in surgeon workload and stress between RPLC and CLC were evaluated. Patient factors and operative outcomes were not significantly different between RPLC and CLC. In the surgeon-reported Surgery Task Load Index, the task demand subscale was significantly higher for RPLC than for CLC（P＝0.005）, although the salivary amylase levels were not significantly different between RPLC and CLC. RPLC was similar to CLC with respect to surgeon stress. Considering workload, the task demand was higher in CLC than in RPLC, which therefore might be an acceptable alternative to CLC for treating benign gallbladder disease

A Comparison of Magnifying Chromoendoscopy Versus Narrow Band Imaging in the Diagnosis of Depth of Invasion for Early Colorectal Cancers

Although chromoendoscopy and narrow band imaging (NBI) are widely used in diagnosing the invasion depth of colorectal cancers, comparative studies of these modalities are lacking. This meta-analysis compared the performance of these two modalities in colorectal cancer diagnosis. MEDLINE, EMBASE, and Cochrane Library were searched for relevant original articles published up to December 20th, 2010. Major criteria for article inclusion were: (i) magnifying chromoendoscopy or NBI was used as a diagnostic modality and pit pattern or vascular pattern was used as a diagnostic classification; (ii) sensitivity and specificity were reported; (iii) absolute numbers of true-positive, false-positive, true-negative, and false-negative cases, or their equivalent, were provided; and (iv) pathology of biopsy, endoscopy, or surgical treatment was used as the reference standard. Sensitivity and specificity were pooled using a random effects model. Regression analysis was performed to compare the discriminatory power between chromoendoscopy and NBI by including a dummy variable. We made the assumption that a positive regression coefficient implied a better discriminatory power for NBI, and vice versa. Of 1846 screened articles, 16 fulfilled all inclusion criteria. Pooled sensitivity for chromoendoscopy and NBI was 0.85 (95% CI: 0.82-0.87) and 0.80 (0.76-0.85), respectively, and specificity was 0.98 (0.97-0.99) and 0.98 (0.97-0.99), respectively. The regression coefficient for chromoendoscopy versus NBI was -0.02 (95%CI: -1.18-1.71). These results indicate that chromoendoscopy and NBI may have similar power for the diagnostic assessment of colonic neoplasms. However, other factors such as convenience, time, and cost still must be taken into account in making the final diagnostic choice

Cost-effectiveness of artificial intelligence for screening colonoscopy: a modelling study

Background: Artificial intelligence (AI) tools increase detection of precancerous polyps during colonoscopy and might contribute to long-term colorectal cancer prevention. The aim of the study was to investigate the incremental effect of the implementation of AI detection tools in screening colonoscopy on colorectal cancer incidence and mortality, and the cost-effectiveness of such tools. Methods: We conducted Markov model microsimulation of using colonoscopy with and without AI for colorectal cancer screening for individuals at average risk (no personal or family history of colorectal cancer, adenomas, inflammatory bowel disease, or hereditary colorectal cancer syndrome). We ran the microsimulation in a hypothetical cohort of 100 000 individuals in the USA aged 50-100 years. The primary analysis investigated screening colonoscopy with versus without AI every 10 years starting at age 50 years and finishing at age 80 years, with follow-up until age 100 years, assuming 60% screening population uptake. In secondary analyses, we modelled once-in-life screening colonoscopy at age 65 years in adults aged 50-79 years at average risk for colorectal cancer. Post-polypectomy surveillance followed the simplified current guideline. Costs of AI tools and cost for downstream treatment of screening detected disease were estimated with 3% annual discount rates. The main outcome measures included the incremental effect of AI-assisted colonoscopy versus standard (no-AI) colonoscopy on colorectal cancer incidence and mortality, and cost-effectiveness of screening projected for the average risk screening US population. Findings: In the primary analyses, compared with no screening, the relative reduction of colorectal cancer incidence with screening colonoscopy without AI tools was 44·2% and with screening colonoscopy with AI tools was 48·9% (4·8% incremental gain). Compared with no screening, the relative reduction in colorectal cancer mortality with screening colonoscopy with no AI was 48·7% and with screening colonoscopy with AI was 52·3% (3·6% incremental gain). AI detection tools decreased the discounted costs per screened individual from $3400 to$3343 (a saving of $57 per individual). Results were similar in the secondary analyses modelling once-in-life colonoscopy. At the US population level, the implementation of AI detection during screening colonoscopy resulted in yearly additional prevention of 7194 colorectal cancer cases and 2089 related deaths, and a yearly saving of US$290 million. Interpretation: Our findings suggest that implementation of AI detection tools in screening colonoscopy is a cost-saving strategy to further prevent colorectal cancer incidence and mortality