Protruding Lesion Research Articles

Dual blockade of IL-4 and IL-13 with dupilumab ameliorates sensorineural olfactory dysfunction in mice with eosinophilic sinonasal inflammation.

Dupilumab, an antibody that binds IL-4Rα and inhibits IL-4 and IL-13 signals, has demonstrated efficacy in chronic rhinosinusitis with nasal polyps (CRSwNP) primarily characterized by type 2 inflammation. Current evidence suggests that the rate of improvement in olfactory dysfunction with dupilumab exceeds that of nasal polyp reduction, yet the underlying mechanism remains undisclosed. We hypothesize that dupilumab may initially ameliorate sensorineural olfactory dysfunction. Male BALB/c mice were intranasally administered ovalbumin and Aspergillus protease for 12 weeks to induce eosinophilic sinonasal inflammation. Dupilumab treatment was also administered. The mice underwent histological assessment, olfactory behavioural test, and gene expression profiling to identify neuroinflammatory markers within the olfactory bulb. Dupilumab treatment resulted in a reduction in the number of mucosal protruding lesions, as well as decreased infiltration of eosinophils and neutrophils, along with a decrease in olfactory sensory neuron injury. Furthermore, there was a downregulation in the mRNA expression related to microglia activation and neuroinflammation in the olfactory bulb. Dupilumab improves the sensorineural pattern of olfactory dysfunction in mice, potentially explaining why olfaction improves more rapidly than polyp reduction in patients with CRSwNP.

Case Report: Gastric Metastasis revealing a Disseminated Skin Melanoma: A Case Report and Literature Review

Abstract Background Melanoma, an aggressive malignant skin cancer, has the ability to spread both locoregionally and to distant sites. The risk of metastasis is correlated to invasion depth and the presence of ulceration. Although gastrointestinal (GI) metastases are uncommon, gastric involvement is particularly rare. Case presentation We report a case of a 62-year-old male who presented with abdominal pain, dyspepsia, anorexia, and weight loss. On physical examination abdominal masses and hepatomegaly were detected. Radiological imaging showed widespread masses in the abdominal and thoracic regions. Upper GI endoscopy identified an umbilicated protruded lesion with central dark pigmentation at the antro-fundic junction. Histopathological examination and immunohistochemical staining were consistent with melanoma. A subsequent rigorous skin examination uncovered a primary malignant skin melanoma. Due to worsening general condition, the patient received palliative hospice care. Conclusion This report highlights the critical need for vigilant skin examination when encountering gastric lesions with dark pigmentation, which led to the identification of initially undetected cutaneous melanoma.

A Case of Proliferative Cystitis Discovered as Protruding Lesion during Inspection of Secondary Infertility

A 42-year-old man visited our hospital complaining of secondary infertility. An abdominal ultrasonography screening incidentally revealed a protruding lesion in the bladder. As the lesion extended from the prostatic urethra and bladder neck, there was a possibility of ejaculation dysfunction after resection of the lesion. Therefore, with the patient's informed consent, sperm cryopreservation was conducted for fertility preservation, and subsequently histological examination was performed by partial transurethral resection of bladder tumor. The pathological findings were proliferative cystitis including all three subtypes (glandularis, cystica, and papillary). Cyclooxygenase-2 immunostaining was positive in cytoplasm; weakly positive in cystic and papillary lesions, and strongly positive in glandular lesions. According to a literature review of massive proliferative cystitis, the patient was the 77th case in Japan. Novel postoperative immunological pharmacotherapies with cyclooxygenase-2 inhibitors have been introduced in recent years.

Exploratory investigation of virtual lesions in gastrointestinal endoscopy using a novel phase‐shift method for three‐dimensional shape measurement

AbstractAccurate measurement of the size of lesions or distances between any two points during endoscopic examination of the gastrointestinal tract is difficult owing to the fisheye lens used in endoscopy. To overcome this issue, we developed a phase‐shift method to measure three‐dimensional (3D) data on a curved surface, which we present herein. Our system allows the creation of 3D shapes on a curved surface by the phase‐shift method using a stripe pattern projected from a small projecting device to an object. For evaluation, 88 measurement points were inserted in porcine stomach tissue, attached to a half‐pipe jig, with an inner radius of 21 mm. The accuracy and precision of the measurement data for our shape measurement system were compared with the data obtained using an Olympus STM6 measurement microscope. The accuracy of the path length of a simulated protruded lesion was evaluated using a plaster model of the curved stomach and graph paper. The difference in height measures between the measurement microscope and measurement system data was 0.24 mm for the 88 measurement points on the curved surface of the porcine stomach. The error in the path length measurement for a lesion on an underlying curved surface was <1% for a 10‐mm lesion. The software was developed for the automated calculation of the major and minor diameters of each lesion. The accuracy of our measurement system could improve the accuracy of determining the size of lesions, whether protruded or depressed, regardless of the curvature of the underlying surface.

Outcomes in colorectal endoscopic submucosal dissection for large protruded lesions: A retrospective multicenter study

Background and study aims: Colorectal endoscopic submucosal dissection (ESD) is increasingly used for treating early-stage colorectal cancer, including large, protruded lesions (LPL). However, the challenges posed by LPLs, especially those accompanied by severe fibrosis or muscle-retracting sign (MRS), remain unclear. This study aims to investigate ESD outcomes for LPL, focusing on factors such as tumor size and, submucosal fibrosis. Patients and methods: In a multicenter retrospective study (June 2012 to May 2023), data from 526 patients with 542 LPL lesions (≥ 2 cm) were analyzed. Parameters included lesion size, procedure time, dissection speed, physician experience, submucosal fibrosis, and adverse events. The tunnel method, including the double tunnel method, was used for cases with severe fibrosis or MRS. Multivariate analysis assessed factors affecting procedure difficulty, particularly LPLs ≥ 4 cm. Results: The study revealed an impressive en bloc resection rate of 97.8% and a curative resection rate of 78.6% for LPLs. Notably, fibrosis and MRS were present in 25% and 18% of 4-cm LPLs, respectively, and their frequency tended to increase as the tumor diameter increased. One treatment strategy for LPLs was the tunneling method, which was used most frequently (41 cases, 7.6%). Factors affecting dissection speed included larger tumor size, submucosal fibrosis, MRS, and physician experience. Conclusions: Treating LPLs through colorectal ESD presents significant challenges, especially in patients with fibrosis and MRS. This study highlights the importance of recognizing these complexities, and that more reliable resection strategy must be established for accurate pathological evaluation.

Construction of deep learning-based convolutional neural network model for automatic detection of fluid hysteroscopic endometrial micropolyps in infertile women with chronic endometritis

Objective(s)Chronic endometritis (CE) is a localized mucosal inflammatory disorder associated with female infertility of unknown etiology, endometriosis, tubal factors, repeated implantation failure, and recurrent pregnancy loss, along with atypical uterine bleeding and iron deficiency anemia. Diagnosis of CE has traditionally relied on endometrial biopsy and detection of CD138(+) endometrial stromal plasmacytes. To develop a less invasive diagnostic system for CE, we aimed to construct a deep learning-based convolutional neural network (CNN) model for the automatic detection of endometrial micropolyps (EMiP), a fluid hysteroscopy (F-HSC) finding recognized as tiny protrusive lesions that are closely related to this disease. Study designThis is an in silico study using archival images of F-HSC performed at an infertility center in a private clinic. A total of 244 infertile women undergoing F-HSC on the days 6–12 of the menstrual cycle between April 2019 and December 2021 with histopathologically-confirmed CE with the aid of immunohistochemistry for CD138 were utilized. ResultsThe archival F-HSC images of 208 women (78 with EMiP and 130 without EMiP) who met the inclusion criteria were finally subjected to analysis. Following preprocessing of the images, half a set was input into a CNN architecture for training, whereas the remaining images were utilized as the test set to evaluate the performance of the model, which was compared with that of the experienced gynecologists. The sensitivity, specificity, accuracy, precision, and F1-score of the CNN model-aided diagnosis were 93.6 %, 92.3 %, 92.8 %, 88.0 %, and 0.907, respectively. The area under the receiver operating characteristic curves of the CNN model-aided diagnosis (0.930) was at a similar level (p > .05) to the value of conventional diagnosis by three experienced gynecologists (0.927, 0.948, and 0.906). ConclusionThese findings indicate that our deep learning-based CNN is capable of recognizing EMiP in F-HSC images and holds promise for further development of the computer-aided diagnostic system for CE.

A157 ASSOCIATION OF SUBMUCOSAL INVASION WITH THE PARIS CLASSIFICATION OF POLYPS IN THE LOWER GASTROINTESTINAL TRACT

Abstract Background Endoscopic evaluation of the colorectum allows for diagnosis of colorectal cancer (CRC) and advanced polyps. In particular, polyps can be described in terms of gross morphology using the Paris classification. Previous work has demonstrated that submucosally invasive (SMI) cancer may correlate with the Paris classification subtypes. Aims To determine whether the Paris classification is associated with SMI in a Canadian setting. Methods We conducted a retrospective single-centre study using data from 2016 to 2023 of patients with colorectal lesions that were referred for endoscopic submucosal dissection (ESD). Using the Paris classification, we classified polyps as either protruding type (0-I) or flat type (0-IIa, 0-IIb, 0-IIc, 0-III) lesions. Protruding type lesions were further classified as sessile (0-Is), pedunculated (0-Ip) and pseudo-pedunculated (0-Isp) subtypes. Mixed lesions, with two concomitant subtypes, were categorized using the higher classification subtype. We categorized polyps as: protruded lesions, including any mixed lesions with a flat lesion; isolated flat elevated lesions; and flat lesions, both mixed and isolated lesions. We also recorded polyp location, prior endoscopic mucosal resection (EMR), previous biopsy, and polyp diameter (in cm), age, sex, and American Society of Anesthesiology (ASA) class. The primary outcome was SMI as identifed on histopathology. We used logistic regression with backward stepwise entry, Fisher exact test with relative risk (RR) and 95% confidence interval (95% CI), and independent samples t-test. Statistical tests were two-tailed and significant at Pampersand:003C0.05. Results In our sample of 130 patients, the mean age was 69.2 years (standard deviation [SD] 10.4), most were male (n=78, 60%), and typically had an ASA score of 3 (n=77, 59.2%). Most polyps occured in the rectum (n=65, 50%) with a mean length was 4.5 cm (SD 2.2 cm). The most common subtype was IIa (n=59, 45.4%). Starting with the covariates of age, sex, ASA, prior EMR, prior biopsy at the same, and length of polyp, the logistic regression model reduced them to three: prior EMR, prior biopsy at the same site, and length. Univariate analysis of these three variables found that there was no significant difference with polyp length and SMI (P=0.147) and no significant association with prior EMR on SMI (RR=0.8 [95% CI 0.3 to 1.9]. The presence of prior biopsies at the same site of the lesions was significantly associated with SMI (RR=2.4 [95% CI 1.2 to 4.7]) Conclusions We did not find that the Paris classification for type of polyp lesion did not correlate with the presence of submucosal invasion, nor did prior EMR, age, sex, or length of polyp. The presence of a prior biopsy, however, did in fact tend to predict submucosal invasion. Future work should aim to incorporate mortality data and response to treatment into the above analysis. Funding Agencies None

Amputation neuroma with a difficult differential diagnosis from perihilar cholangiocarcinoma:a case report

Biliary amputation neuroma is a rare benign tumor that develops due to the peribiliary dissection of nerve fibers during cholecystectomy, a common bile duct surgery, or lymph node dissection performed in gastric cancer surgery. We report a case of amputation neuroma that presented a challenging differential diagnosis from perihilar cholangiocarcinoma. A 64-year-old man, who had undergone open cholecystectomy 30 years ago, was incidentally found to have a bile duct tumor during computed tomography (CT) following surgery for renal cell carcinoma. He had no specific symptoms, and blood test results showed only a slight elevation in alkaline phosphatase levels. Contrast-enhanced CT revealed a 10-mm solid tumor with contrast effect in the common bile duct. On cholangiography, the tumor appeared as a protruding lesion with a smooth surface unilaterally. Given the atypical findings suggestive of cholangiocarcinoma, three bile duct biopsies were performed. Pathological examination did not rule out adenocarcinoma. The patient opted for surgery;however, an intraoperative rapid histological examination confirmed a benign disease, thereby avoiding extensive surgery. Consequently, a minimally invasive bile duct resection was performed. Postoperative histopathological examination revealed the tumor to be an amputation neuroma. Biliary amputation neuromas are characterized as unilateral protruding lesions with contrast effect or benign strictures. If such findings are observed in a patient with a history of surgery around the bile duct, the possibility of an amputation neuroma should be considered. However, completely ruling out malignancy preoperatively, even when suspecting amputation neuroma, can be challenging;therefore, considering surgery to achieve a definitive diagnosis is reasonable. During surgery, a rapid intraoperative histological examination is useful to avoid extensive procedures. In conclusion, diagnosing an amputation neuroma before surgery can be difficult, as it can mimic malignant tumors such as bile duct cancers. In this case, although a preoperative diagnosis of amputation neuroma was not feasible, performing a rapid intraoperative pathological examination helped avoid extensive surgery.

Paraganglioma with high-grade intraepithelial neoplasia in the oesophagus treated by endoscopic submucosal dissection.

A 37-year-old woman was hospitalised with a 4-month history of retrosternal pain. Gastroscopy revealed a protrusion lesion of approximately 0.6 cm in diameter in the left wall of the oesophagus, approximately 27 cm from the incisor (Fig. 1). Consequently, one biopsy specimen was taken from the oesophagus. Based on the pathology and immunohistochemistry findings, the patient was initially diagnosed with paraganglioma with high-grade squamous intraepithelial neoplasia. The patient underwent endoscopic submucosal dissection 12 days after the biopsy. The protrusion lesion was again observed under gastroscopy, with visible scarring on the surface (Fig. 2A). A hypoechoic and heterogeneous mass of about 7.1 mm × 2.0 mm in the muscularis mucosae layer was detected on endoscopic ultrasonography (Fig. 2B). The mass was excised after submucosal injection of adrenaline, melphalan, and glycerol fructose injection (Fig. 2C). The postoperative gross specimen was a mucosal tissue measuring 2 cm × 1.8 cm × 0.2 cm, with a bulging mass underneath (Fig. 2D). The results of immunohistochemical analysis were positive for CD56, Syn, CK8/18, LCK, and S-100 and negative for SSTR2 (Fig. 3D, E). Expression of wild-type P53, focal positivity of CgA, and weak positivity of NSE were noted. The Ki-67 labelling index was 1–2%. The diagnosis of paraganglioma with high-grade squamous intraepithelial neoplasia was confirmed based on the histopathology findings (Fig. 3A, B, C). The patient recovered well during the follow-up. Fig. 2(A) The protrusion lesion was found again under gastroscopy, with visible scarring on the surface. (B) Endoscopic ultrasonography detected a hypoechoic and heterogeneous mass of about 7.1 mm × 2.0 mm in the muscularis mucosae layer. (C) Adrenaline, melphalan and glycerol fructose injection was injected in the submucosa after the lesion was marked with a dual knife. (D) Gross specimen after endoscopic submucosal dissection. View Large Image Figure Viewer Download Hi-res image Fig. 3Microscopic examination. (A) Significant cytological atypia in squamous epithelium with continuous basement membrane, and arrangement of the cells in nests (“Zellballen”) in muscularis mucosae. (HE stain × 4) (B) The tumour was composed of chief cells and sustentacular cells. (HE stain × 10) (C) The chief cell is polygonal with a fine granular cytoplasm of acidophilia as well as basophilia. The nucleus is round to elliptical. The sustentacular cells of spindle-shape are distributed around the tumour cell nests or interdigitated amongst the sustentacular cells. (HE stain × 40) (D) positivity of S-100 protein (× 10). (E) positivity of Syn. (× 10). View Large Image Figure Viewer Download Hi-res image

Gastric Foveolar-type Adenocarcinoma with Raspberry-like Appearance in a Helicobacter pylori-uninfected Stomach: A Long-term Retrospective Follow-up of 16 Years.

Esophagogastroduodenoscopy in a 58-year-old man revealed a protruding lesion measuring 6 mm in diameter in the fornix. An endoscopic biopsy of the lesion indicated well-differentiated adenocarcinoma.The lesion was resected by polypectomy. According to the Japanese histologic diagnostic criteria, we made a final diagnosis of early gastric cancer (U, Gre, 6×6 mm,Type 0-I, tub1, pT1a (M), pUl0, Ly0, V0, pHM0, pVM0). A retrospective review of the endoscopic images showed that this lesion had already been present in the images taken 16 years ago. The size and morphology of the lesion were the same as those of the first detected lesion.

Emergent endoscopic submucosal dissection for a polypoid fibroadipose tumor accidentally disgorged from the mouth: an organ-preserving minimally invasive treatment.

Video 1The yellow protruded lesion at the larynx is different from the main lesion.

Transanal local excision for mucosal prolapse syndrome.

A 46-year-old male visited our hospital with blood stool and constipation. Colonoscopy revealed a broad-based protruded lesion in the rectum.The endoscopic ultrasonography showed the lesion invaded the submucosa, and the boundary between the local and intrinsic muscular layer was not clear. Transanal local excision was conducted, the pathology showed a rare case of mucosal prolapse syndrome merging chronic suppurative inflammation.

Endoscopic findings of gastric neoplasms in familial adenomatous polyposis are associated with the phenotypic variations and grades of dysplasia.

Patients with familial adenomatous polyposis (FAP) are at increased risk of developing gastric neoplasms. However, endoscopic findings have not been sufficiently investigated. We investigated the phenotypic expression of gastric adenoma (low-grade dysplasia) and gastric cancer (high-grade dysplasia or carcinoma) in patients with FAP and clarified their relationships to endoscopic findings. Of 29 patients with FAP who underwent esophagogastroduodenoscopy between 2005 and 2020, 11 (38%) had histologically confirmed gastric neoplasms, including 23 lesions of gastric adenoma and 9 lesions of gastric cancer. The gastric neoplasms were classified into 3 phenotypes (gastric, mixed, or intestinal type) according to the immunostaining results and evaluated for location (U or M region: upper or middle third of the stomach or L region: lower third of the stomach), color (same as the background mucosa, whitish, or reddish), macroscopic type (elevated, flat, or depressed), background mucosal atrophy (present or absent), fundic gland polyps in the surrounding mucosa (present or absent), and morphologic changes in tumor size. Elevated whitish gastric adenomas were further subdivided by macroscopic type (flat elevated, protruded, or elevated with a central depression) and color (milky- or pinkish-white). The gastric adenomas included gastric (11/23, 48%), mixed (4/23, 17%), and intestinal (8/23, 35%) phenotypes. In contrast, no lesions of gastric cancers showed a gastric phenotype (0/9, 0%), while 5 (56%) and 4 (44%) lesions were intestinal and mixed phenotypes, respectively. Gastric cancers were significantly more likely than gastric adenomas to present as reddish depressed lesions with gastric atrophy. All gastric-type adenomas occurred in non-atrophic mucosa, in mucosa with fundic gland polyps in the periphery, in the U or M region, and as flat elevated or protruded lesions with a milky-white color. Half of the lesions increased in size. Meanwhile, the typical endoscopic features of intestinal-type adenomas included occurrence in the L region and elevated pinkish-white lesions with central depression. None of the intestinal-type adenomas increased in size during the observation period. We believe that these endoscopic features will be useful for the prompt diagnosis and appropriate management of gastric neoplasms in patients with FAP.

S367 Endoscopic Eversion and Stent-Assisted Strangulation for the Management of an Intraductal Papillary Neoplasm of the Bile Duct: A Minimally Invasive Technique for Non-Surgical Candidates

Introduction: Intraductal papillary neoplasms of the bile duct (IPNB) are uncommon lesions that may accompany risk for malignancy. Management is often surgical and may be associated with significant postoperative morbidity and mortality. Case Description/Methods: An 80-year-old female with a history of hepatocellular carcinoma (HCC) presented for management of jaundice and sepsis after microwave ablation of HCC. Computed tomography (CT) imaging demonstrated intra and extrahepatic biliary ductal dilation with a 19 mm soft tissue density in the distal common bile duct (CBD). Index labs depicted leukocytosis, hyperbilirubinemia, and elevated lactate. Endoscopic ultrasound (EUS) delineated a round, hypoechoic intraductal CBD lesion. The pancreas and ampulla were normal. Endoscopic retrograde cholangiopancreatography (ERCP) confirmed a distal CBD filling defect. Biliary sphincterotomy was performed and balloon sweeping revealed a frond-like partially protruding polypoid lesion suggestive of an IPNB. Due to non-surgical candidacy, we decided to perform a complete eversion with subsequent full prolapse of the lesion by using a biliary extraction balloon. This was followed by the placement of a biliary plastic stent to assist with strangulation of the base of the lesion. Biopsies were consistent with a papillary neoplasm with intestinal differentiation, confirming our findings of an IPNB, without accompanying high-grade dysplasia or carcinoma. Interval surveillance ERCP 3 months later revealed no protruding lesion from the major papilla, no residual filling defects on cholangiogram, and sweeping of the biliary tree uncovered no contents. Cholangioscopy demonstrated segmental mucosal irregularity with mild granular tissue in the mid/distal bile duct wall; however, cholangioscopy-guided intraductal biopsies and brushings showed benign reactive tissue and no recurrent IPNB. At 5 months of follow-up, the patient continues to do well. Discussion: IPNB is a rare biliary lesion. Radical surgical resection has been the mainstay of curative treatment. However, a few recent cases have described endoluminal radiofrequency ablation as an alternative therapy. To the best of our knowledge, this is the first reported case of balloon-assisted eversion combined with stent-assisted strangulation of an IPNB leading to spontaneous removal. In non-surgical candidates, this technique may be advantageous to minimize adverse operative outcomes, improve patient tolerance, and decrease cost. Watch the video at https://tinyurl.com/ACGAbstractS367

A rare gastric foveolar-type adenoma with lanthanum deposition in a Helicobacter pylori–uninfected patient

A 53-year-old man undergoing hemodialysis for chronic kidney disease had been taking lanthanum carbonate for the previous 3 years. EGD revealed a 5-mm reddish protruding lesion, with a raspberry-like appearance and white deposits on its surface, in the upper third section of the Helicobacter pylori–uninfected stomach (A). Narrow-band imaging (NBI; Olympus, Tokyo, Japan) along with texture and color enhancement imaging (TXI; Olympus)—assisted endoscopy revealed the presence of white deposits considered to be of lanthanum, as confirmed by different endoscopic results from white opaque substance (WOS), light blue crest (LBC), and white globe appearance (WGA) (B, C).

Artificial Intelligence and Device-Assisted Enteroscopy: Automatic Detection of Enteric Protruding Lesions Using a Convolutional Neural Network.

INTRODUCTION:Device-assisted enteroscopy (DAE) plays a major role in the investigation and endoscopic treatment of small bowel diseases. Recently, the implementation of artificial intelligence (AI) algorithms to gastroenterology has been the focus of great interest. Our aim was to develop an AI model for the automatic detection of protruding lesions in DAE images.METHODS:A deep learning algorithm based on a convolutional neural network was designed. Each frame was evaluated for the presence of enteric protruding lesions. The area under the curve, sensitivity, specificity, and positive and negative predictive values were used to assess the performance of the convolutional neural network.RESULTS:A total of 7,925 images from 72 patients were included. Our model had a sensitivity and specificity of 97.0% and 97.4%, respectively. The area under the curve was 1.00.DISCUSSION:Our model was able to efficiently detect enteric protruding lesions. The development of AI tools may enhance the diagnostic capacity of deep enteroscopy techniques.

Application of Endoscopic Ultrasound Combined with Multislice Spiral CT in Diagnosis and Treatment of Patients with Gastrointestinal Eminence Lesions.

Objective To evaluate the application of endoscopic ultrasound (EUS) combined with multislice spiral CT (MSCT) in the diagnosis and treatment of patients with gastric eminence lesions. Methods A total of 160 patients with gastric eminence lesions enrolled in our hospital from June 2018 to June 2021 were included and received EUS and MSCT. The results of the two examinations and the postoperative pathological results were compared. Results The common pathological types of gastric eminence lesions include polyps and stromal tumors, with the most common sites of lesions in the gastric antrum, followed by the fundus of the stomach and the gastric body. Gastric eminence lesions mostly originate from the mucosal layer and muscularis mucosa, accounting for 83.13% of the total. With pathological results as the gold standard, the detection rate of MSCT was 90.63%, and that of EUS was 78.13%. With the joint diagnosis as a reference, the receiver operating curve (ROC) revealed a higher diagnostic efficiency of MSCT and EUS. Conclusion The accuracy of MSCT in the diagnosis of gastric eminence lesions is significantly higher than that of EUS, both of which can offer useful guidance for the choice of endoscopic treatment methods. The combination of MSCT and EUS examination before endoscopic gastroscopy may provide a better treatment efficacy on gastric protruding lesions with high safety.

Performance of a Deep Learning System for Automatic Diagnosis of Protruding Lesions in Colon Capsule Endoscopy.

Background: Colon capsule endoscopy (CCE) is an alternative for patients unwilling or with contraindications for conventional colonoscopy. Colorectal cancer screening may benefit greatly from widespread acceptance of a non-invasive tool such as CCE. However, reviewing CCE exams is a time-consuming process, with risk of overlooking important lesions. We aimed to develop an artificial intelligence (AI) algorithm using a convolutional neural network (CNN) architecture for automatic detection of colonic protruding lesions in CCE images. An anonymized database of CCE images collected from a total of 124 patients was used. This database included images of patients with colonic protruding lesions or patients with normal colonic mucosa or with other pathologic findings. A total of 5715 images were extracted for CNN development. Two image datasets were created and used for training and validation of the CNN. The AUROC for detection of protruding lesions was 0.99. The sensitivity, specificity, PPV and NPV were 90.0%, 99.1%, 98.6% and 93.2%, respectively. The overall accuracy of the network was 95.3%. The developed deep learning algorithm accurately detected protruding lesions in CCE images. The introduction of AI technology to CCE may increase its diagnostic accuracy and acceptance for screening of colorectal neoplasia.

A case of diverticulum of the appendiceal base resembling a submucosal tumor of the cecum under colonoscopy: a hitherto undescribed lesion

BackgroundDiverticulosis of the appendix is an uncommon clinical entity, and a preoperative diagnosis is often difficult. Herein we report an unusual case of appendiceal diverticulosis.Case presentationA 72-year-old male was referred to our hospital to examine the cause of hematochezia. A colonoscopy study showed a protruding lesion resembling a submucosal tumor (SMT), approximately 20 mm in diameter, at the site around the appendiceal orifice of the cecum. An abdominal computed tomography and magnetic resonance imaging showed a cystic lesion at the appendiceal base. The lesion was clinically diagnosed as a cystic tumor of the appendix, but the possibility of a malignant tumor could not be excluded. Therefore, a laparoscopic ileocecal resection with lymph node dissection was performed. The pathological examination of the resected specimen revealed that the lesion was a diverticulum (pseudodiverticulum) occurring solitarily at the appendiceal base, in which the mucosal layer of the appendix was invaginated into the submucosa of the adjacent cecum, thus forming an SMT-like lesion.ConclusionTo our knowledge, this is the first case report in the English literature showing that an appendiceal diverticulum can manifest as an SMT-like lesion in the cecum. This condition should be recognized as a differential diagnosis for such lesions.

Sporadic foveolar-type adenoma in gastric body/antrum junction with gastritis cystica profunda

BackgroundSporadic gastric foveolar-type adenomas are extremely rare and are usually small, flat or slightly raised lesions that occur in the oxyntic mucosa.Case presentationWe reported here a case of a 70-year-old female with a sporadic gastric foveolar-type adenoma occurring in the mucosa at the junction of the gastric body/antrum. The adenoma was a protruding lesion of 2 × 1.8 cm sized, causing symptoms of upper gastrointestinal bleeding, and the basal and surrounding mucosa showed pseudopyloric gland metaplasia without atrophy, intestinal metaplasia, H. pylori infection, or active inflammation. It had somatic mutations in both APC and KRAS genes.ConclusionsThis is the first reported case of a large sporadic gastric foveolar-type adenoma that occurred in the mucosa of pseudopyloric gland metaplasia and with Gastritis Cystica Profunda, which modify our understanding of the morphological features and molecular underpinnings of this type of lesion.