Rectal implantation cyst successfully diagnosed using endoscopic myotomy and endoscopic ultrasonography

An 81-year-old woman who underwent laparoscopic-assisted low anterior resection with instrumented anastomosis using the double stapling technique for rectal cancer 5 years ago was found to have an enlarged anastomotic mass on computed tomography. On colonoscopy, the anastomotic mass was observed as a 30-mm-sized subepithelial lesion, which was presumed to be the submucosa on endoscopic ultrasonography (EUS). EUS-guided fine-needle aspiration was performed; however, no cellular components were collected. Therefore, endoscopic submucosal dissection (ESD) was performed to remove the entire anastomotic mass. However, any lesion in the submucosa was not detected during ESD, and the lesion was suspected to be located deeper than the submucosa. Therefore, EUS was performed from the muscule layer just below the dissected submucosa, and the mass was detected outside the muscle layer in contact with the rectal wall. Upon endoscopic incision of the muscle layer, milky white mucus was excreted into the rectal lumen. Subsequently, the scope was advanced to an area outside the muscle layer where the mass was located, which was a closed lumen with mucus retention. Surface biopsy of the closed lumen revealed normal colonic mucosa. Therefore, the subepithelial lesion was diagnosed as an implantation cyst arising outside the rectal wall.

Early gastric cancer presenting as a typical submucosal tumor cured by endoscopic submucosal dissection: A case report

BACKGROUND

Submucosal tumor (SMT)-like gastric cancer is rare, and almost all cases undergo curative surgical treatment because the submucosal layer is usually deeply invaded by tumor cells or because histopathologic types of SMT-like gastric cancer are undifferentiated or poorly differentiated. No report has been issued on an SMT-like gastric cancer cured by endoscopic resection alone or on changes in the endoscopic features of this type of tumor over several years.

CASE SUMMARY

We describe an exceptional case of a 53-year-old male with a 1.5 cm-sized SMT-like lesion covered by normal-appearing mucosa discovered by esophagogastroduodenoscopy (EGD) at the gastric antrum. Endoscopic ultrasound (EUS) visualized a homogeneous, well-circumscribed hypoechogenic lesion arising from the second sonographic layer with associated subtle obliteration of the third sonographic layer. Initial endoscopic biopsy was negative for neoplasm. The patient refused to undergo an invasive procedure and was subsequently lost to follow-up. Three years after initial detection, EGD revealed the lesion had become markedly erythematous, and at 4 years after initial EGD it had increased in size to 1.8 cm and developed a central ulcer and a heterogeneous EUS echo. Finally, endoscopic submucosal dissection (ESD) was performed, and histopathologic examination revealed a moderately differentiated adenocarcinoma had minutely invaded the submucosal layer (invasion depth 169 μm) but without lymphovascular invasion and with negative resection margins. Fortunately, no additional surgical treatment was required. He has been followed for 4 years after ESD without any evidence of local or distant recurrence.

CONCLUSION

This report describes an extremely rare case of early gastric cancer presenting as SMT that was cured by ESD after a treatment delay of 4 years and the endoscopic changes that occurred during this period. The report highlights the importance of considering the possibility of gastric cancer when SMT is encountered in clinical practice.

Artificial intelligence-based diagnosis of upper gastrointestinal subepithelial lesions on endoscopic ultrasonography images

BACKGROUND

Endoscopic ultrasonography (EUS) is useful for the differential diagnosis of subepithelial lesions (SELs); however, not all of them are easy to distinguish. Gastrointestinal stromal tumors (GISTs) are the commonest SELs, are considered potentially malignant, and differentiating them from benign SELs is important. Artificial intelligence (AI) using deep learning has developed remarkably in the medical field. This study aimed to investigate the efficacy of an AI system for classifying SELs on EUS images.

METHODS

EUS images of pathologically confirmed upper gastrointestinal SELs (GIST, leiomyoma, schwannoma, neuroendocrine tumor [NET], and ectopic pancreas) were collected from 12 hospitals. These images were divided into development and test datasets in the ratio of 4:1 using random sampling; the development dataset was divided into training and validation datasets. The same test dataset was diagnosed by two experts and two non-experts.

RESULTS

A total of 16,110 images were collected from 631 cases for the development and test datasets. The accuracy of the AI system for the five-category classification (GIST, leiomyoma, schwannoma, NET, and ectopic pancreas) was 86.1%, which was significantly higher than that of all endoscopists. The sensitivity, specificity, and accuracy of the AI system for differentiating GISTs from non-GISTs were 98.8%, 67.6%, and 89.3%, respectively. Its sensitivity and accuracy were significantly higher than those of all the endoscopists.

CONCLUSION

The AI system, classifying SELs, showed higher diagnostic performance than that of the experts and may assist in improving the diagnosis of SELs in clinical practice.

Optimal number of needle punctures in endoscopic ultrasound-guided fine-needle biopsy for gastric subepithelial lesions without rapid on-site evaluation

PURPOSE

The utility of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) for gastric subepithelial lesions (SELs) has been reported. In this study, we examined the optimal number of needle punctures during EUS-FNB for gastric SELs without rapid on-site evaluation (ROSE). The factors that allowed for a single needle puncture to arrive at the correct diagnosis were also analyzed.

METHODS

We conducted a retrospective study of all patients who underwent EUS-FNB to evaluate gastric SELs between April 2015 and September 2020; 51 patients with 57 gastric SELs were enrolled. The optimal number of needle punctures was determined when additional needle passes did not increase diagnostic sensitivity by more than 10%. Factors allowing for only a single needle puncture to arrive at the correct diagnosis were identified by univariate and multivariate logistic regression analyses.

RESULTS

EUS-FNB resulted in a definitive final diagnosis in 48 of 57 lesions (84%). Lesions in the gastric body (odds ratio [OR] 6.15, 95% confidence interval [CI] 1.75-21.6; P < 0.01) and lesions punctured using a 22G Franseen needle (OR 3.61, 95% CI 1.07-12.3; P = 0.04) were independent factors that allowed for only a single needle puncture to arrive at the correct diagnosis. The optimal number of needle punctures for lesions using a 22G Franseen needle in the gastric body and other lesions was two and three, respectively.

CONCLUSION

The optimal number of needle punctures in EUS-FNB for gastric SELs without ROSE was two or three, depending on the location and type of needle used.

Localized gastric amyloidosis diagnosed by endoscopic ultrasound-guided fine-needle aspiration

A 49-year-old man was found to have an elevated lesion on esophagogastroduodenoscopy (EGD) for gastric cancer screening. This lesion had been noted in EGD 13 years earlier, but the patient had not received EGD since then. Endoscopy showed a relatively soft subepithelial lesion (SEL) in the gastric antrum. In addition, endoscopic ultrasonography (EUS) showed a 20-mm-sized, slightly non-uniform hypoechoic mass in the submucosa. Since the diagnosis could not be confirmed by mucosal biopsy, EUS-guided fine-needle aspiration (EUS-FNA) was performed. Hematoxylin-eosin staining of EUS-FNA samples revealed deposition of acidophilic unstructured materials. The structure was positive on Congo red staining, and green polarized light was also observed under a polarizing microscope. Moreover, it was resistant to potassium permanganate reaction, negative for serum amyloid A protein, positive for anti-λ chain antibody, and negative for anti-κ chain, anti-amyloid A, anti-transthyretin, and anti-β2-microglobulin antibodies. Therefore, the lesion was diagnosed as AL-λ-type amyloidosis. No systemic amyloidosis findings were found; thus, the patient was finally diagnosed with localized gastric AL amyloidosis. If an SEL is seen without disease-specific endoscopic findings, amyloidosis should be included in the differential diagnosis, and EUS-FNA can contribute to obtaining tissue samples in such cases.

Enterolith at the ileocecal valve mimicking a subepithelial mass

A 32-year-old woman presented with chronic constipation for three years. Colonoscopy revealed a 2.5 cm subepithelial tumor-like lesion at the ileocecal (IC) valve with protrusion of the lesion into the lumen. A CT scan of the abdomen showed an oval-shape laminated calcified lesion adhered to the IC valve and several gallstones. An exploratory laparotomy to enterotomy with stone extraction and open cholecystectomy was performed. Operative findings showed stone erosion into the ileal wall with the lesion being covered with colonic mucosa. Pathologic examination of stones from the intestinal wall revealed an enterolith. The case exemplifies the infrequent cause of a subepithelial lesion of the gastrointestinal tract and a rare presentation of an enterolith as a subepithelial lesion within the terminal ileal wall.

Gastric carcinoma with lymphoid stroma diagnosed by endoscopic ultrasound-guided fine-needle aspiration

A 78-year-old man with a subepithelial lesion (SEL) in the gastric body and two carcinomas in the gastric antrum was referred to our hospital. Following a diagnosis of SEL, the patient was followed-up by esophagogastroduodenoscopy annually for 4 years. Although the SEL had increased in size over the years, histological evaluation of the forceps biopsies did not reveal any significant findings. We detected a hypoechoic mass in the submucosa by endoscopic ultrasonography, and suspected the lesion to be an aberrant pancreas or mesenchymal tumor. The patient first underwent endoscopic submucosal dissection for the 2 gastric cancers. Histological examination of the resected specimens revealed intramucosal well-differentiated tubular adenocarcinomas. Next, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed for the gastric SEL. Aspirated specimens revealed an adenocarcinoma with lymphocyte infiltration. The lesion was diagnosed as a gastric carcinoma with lymphoid stroma (GCLS). Subsequently, he underwent distal gastrectomy, and the surgical specimen was confirmed as GCLS corresponding to preoperative diagnosis. In addition, the adenocarcinoma cells were positive for Epstein-Barr (EB) virus-encoded small RNA-1 by in situ hybridization. Finally, the lesion was diagnosed as GCLS associated with EB virus. Thus, EUS-FNA is advantageous for diagnosing GCLS associated with EB virus.

Efficacy of endoscopic ultrasound with artificial intelligence for the diagnosis of gastrointestinal stromal tumors

BACKGROUND

Although endoscopic ultrasound (EUS) is reported to be suitable for determining the layer from which subepithelial lesions (SELs) originate, it is difficult to distinguish gastrointestinal stromal tumor (GIST) from non-GIST using only EUS images. If artificial intelligence (AI) can be used for the diagnosis of SELs, it should provide several benefits, including objectivity, simplicity, and quickness. In this pilot study, we propose an AI diagnostic system for SELs and evaluate its efficacy.

METHODS

Thirty sets each of EUS images with SELs ≥ 20 mm or < 20 mm were prepared for diagnosis by an EUS diagnostic system with AI (EUS-AI) and three EUS experts. The EUS-AI and EUS experts diagnosed the SELs using solely the EUS images. The concordance rates of the EUS-AI and EUS experts' diagnoses were compared with the pathological findings of the SELs.

RESULTS

The accuracy, sensitivity, and specificity for SELs < 20 mm were 86.3, 86.3, and 62.5%, respectively for the EUS-AI, and 73.3, 68.2, and 87.5%, respectively, for the EUS experts. In contrast, accuracy, sensitivity, and specificity for SELs ≥ 20 mm were 90.0, 91.7, and 83.3%, respectively, for the EUS-AI, and 53.3, 50.0, and 83.3%, respectively, for the EUS experts. The area under the curve for the diagnostic yield of the EUS-AI for SELs ≥ 20 mm (0.965) was significantly higher than that (0.684) of the EUS experts (P = 0.007).

CONCLUSION

EUS-AI had a good diagnostic yield for SELs ≥ 20 mm. EUS-AI has potential as a good option for the diagnosis of SELs.

Gastric Dieulafoy's lesion with subepithelial lesion-like morphology

Most cases of Dieulafoy's lesion, a rare cause of upper gastrointestinal bleeding, occur in the upper gastric corpus, usually with no edematous bulging or fold convergence around the mucosal defect. This report describes a case of Dieulafoy's lesion with subepithelial lesion (SEL)-like morphology. Endoscopic treatment by hemoclipping was difficult. Because of repeated bleeding, abdominal dynamic contrast computed tomography (CT) was conducted. Results showed a large caliber, tortuous artery branching directly from the celiac artery and feeding into the gastric wall of the gastric fundus. Rupture of this vessel in the submucosa was thought to be responsible for the SEL-like morphology. All findings indicated endoscopic treatment from the gastric mucosal side was too difficult. Therefore, we treated the lesion using interventional radiology (IR) technique of vascular embolization. If an SEL-like Dieulafoy's lesion cannot be treated by endoscopic hemostasis, then IR might be necessary to treat the vascular anomaly.

Superiority of mucosal incision-assisted biopsy over ultrasound-guided fine needle aspiration biopsy in diagnosing small gastric subepithelial lesions: a propensity score matching analysis

BACKGROUND

Gastric subepithelial lesions, including gastrointestinal stromal tumors, are often found during routine gastroscopy. While endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) has been the gold standard for diagnosing gastric subepithelial lesions, alternative open biopsy procedures, such as mucosal incision-assisted biopsy (MIAB) has been reported useful. The aim of this study is to evaluate the efficacy of MIAB for the diagnosis of gastric SELs compared with EUS-FNAB.

METHODS

We retrospectively analyzed medical records of 177 consecutive patients with gastric SELs who underwent either MIAB or EUS-FNAB at five hospitals in Japan between January 2010 and January 2018. Diagnostic yield, procedural time, and adverse event rates for the two procedures were evaluated before and after propensity-score matching.

RESULTS

No major procedure-related adverse events were observed in either group. Both procedures yielded highly-accurate diagnoses once large enough samples were obtained; however, such successful sampling was more often accomplished by MIAB than by EUS-FNAB, especially for small SELs. As a result, MIAB provided better diagnostic yields for SELs smaller than 20-mm diameter. The diagnostic yields of both procedures were comparable for SELs larger than 20-mm diameter; however, MIAB required significantly longer procedural time (approximately 13 min) compared with EUS-FNAB.

CONCLUSIONS

Although MIAB required longer procedural time, it outperformed EUS-FNAB when diagnosing gastric SELs smaller than 20-mm diameter.

Gastric adenocarcinoma mimicking a submucosal tumor: A case report

BACKGROUND

Submucosal tumor (SMT)-like early-stage gastric cancer (GC) has rarely been reported. It is difficult to consider the possibility of GC and differentiate it from other submucosal lesions.

CASE SUMMARY

We present the case of a 50-year-old male patient with a 1.6 cm SMT-like flat elevated lesion covered by congested mucosa on the gastric angle. Magnifying endoscopy with narrow-band imaging, endoscopic biopsy, endoscopic ultrasound, and computed tomography were performed for diagnosis. Endoscopic submucosal dissection and gastrectomy with lymph node dissection were performed. The post-resection pathological analysis led to a final diagnosis of GC (Bormann type I, T1bN2M0).

CONCLUSION

GC should be considered when detecting an SMT-like lesion in the stomach.

Prospective comparative study of endoscopic ultrasonography-guided fine-needle biopsy and unroofing biopsy

BACKGROUND AND AIM

Adequate tissue acquisition is important in making treatment decisions for patients with upper gastrointestinal subepithelial tumors (SETs). This study aimed to compare the outcomes of endoscopic ultrasonography-guided fine-needle biopsy (EUS-FNB) with those of the unroofing biopsy technique.

METHODS

This study was a single-center, prospective comparative study conducted at Severance Hospital, Yonsei University College of Medicine. A total of 39 patients with SETs ≥15 mm were enrolled between January 2016 and August 2017.

RESULTS

Of the 39 patients, 28 underwent biopsy with both techniques (4 underwent only unroofing and 7 underwent only EUS-FNB). Histological diagnosis was made with EUS-FNB in 64.3% and unroofing biopsy in 78.6% (p = 0.344), and immunohistochemical diagnosis was made with EUS-FNB in 46.4% and unroofing biopsy in 67.9% (p = 0.180). In the subgroup analysis (28 patients), there was no significant difference in diagnostic yield between the 2 methods The mean procedural time with EUS-FNB was shorter than that with unroofing biopsy (p < 0.001). The larger SET (≥ 20 mm) (p = 0.035) and satisfaction of procedure (p = 0.019) were positively associated with successful histological diagnosis by EUS-FNB.

CONCLUSIONS

There was no significant difference in the histological diagnostic yield for SETs between the EUS-FNB and unroofing biopsy techniques (CinicalTrials.gov. identifier NCT02646241).

Early gastric cancer with lymphoid stroma presenting as a subepithelial lesion diagnosed by endoscopic submucosal dissection

A 53-year-old man underwent an esophagogastroduodenoscopy that showed a 20-mm subepithelial lesion in the middle gastric body. Endoscopic ultrasound revealed a hypoechoic mass located in the submucosa. Biopsy specimens revealed a benign gastric mucosa with severe lymphocytic infiltration in the submucosa. Malignant lymphoma or gastric cancer with lymphoid stroma was suspected. We performed endoscopic submucosal dissection for definitive diagnosis. Histological examination showed undifferentiated adenocarcinoma, which showed positive Epstein-Barr virus-encoded RNA in situ hybridization results, invading the submucosa mixed with dense lymphocytic infiltration. Thus, Epstein-Barr virus-positive gastric cancer with lymphoid stroma was diagnosed. Gastric cancer with lymphoid stroma is a rare subtype of gastric cancer, which is associated with Epstein-Barr virus infection; it sometimes appears as a subepithelial lesion, which makes it difficult to diagnose using standard biopsy. Endoscopic submucosal dissection was useful in obtaining a sufficient tissue for full histological assessment, including immunostaining.

Gastric metastasis from ovarian adenocarcinoma presenting as a subepithelial tumor and diagnosed by endoscopic ultrasound-guided tissue acquisition

We describe an uncommon case of a patient with a metastatic adenocarcinoma of ovarian origin presented as a gastric subepithelial tumor (SET) and that was diagnosed by endoscopic ultrasound fine-needle biopsy (EUS-FNB). Malignant gastric lesions are rarely metastatic and the primary tumor is mainly breast, lung, esophageal cancer or cutaneous melanoma. Gastric metastasis from ovarian cancer is unusual, presenting synchronously with the primary tumor but also several years later than the initial diagnosis. From an endoscopic point of view, gastric metastasis does not present specific features. They may mimic both a primary gastric tumor or, less frequently, an SET. This case demonstrates the importance of EUS-FNB in distinguishing SETs and how this may alter treatment and prognosis.

High clinical impact and diagnostic accuracy of EUS-guided biopsy sampling of subepithelial lesions: a prospective, comparative study

Background

In a tertiary center setting we aimed to study the diagnostic accuracy and clinical impact of EUS-guided biopsy sampling (EUS-FNB) with a reverse bevel needle compared with that of fine needle aspiration (EUS-FNA) in the work-up of subepithelial lesions (SEL).

Methods

All patients presenting with SELs referred for EUS-guided sampling were prospectively included in 2012–2015. After randomization of the first pass modality, dual sampling with both EUS-FNB and EUS-FNA was performed in each lesion. Outcome measures in an intention-to-diagnose analysis were the diagnostic accuracy, technical failures, and adverse events. The clinical impact was measured as the performance of additional diagnostic procedures post-EUS and the rate of unwarranted resections compared with a reference cohort of SELs sampled in the same institution 2006–2011.

Results

In 70 dual sampling procedures of unique lesions (size: 6–220 mm) the diagnostic sensitivity for malignancy and the overall accuracy of EUS-FNB was superior to EUS-FNA compared head-to-head (90 vs 52%, and 83 vs 49%, both p < 0.001). The adverse event rate of EUS-FNB was low (1.2%). EUS-FNB in 2012–2015 had a positive clinical impact in comparison with the reference cohort demonstrated by less cases referred for an additional diagnostic procedure, 12/83 (14%) vs 39/73 (53%), p < 0.001, and fewer unwarranted resections in cases subjected to surgery, 3/48 (6%) vs 12/35 (34%), p = 0.001.

Conclusions

EUS-FNB with a reverse bevel needle is safe and superior to EUS-FNA in providing a conclusive diagnosis of subepithelial lesions. This biopsy sampling approach facilitates a rational clinical management and accurate treatment.

Electronic supplementary material

The online version of this article (doi:10.1007/s00464-017-5808-2) contains supplementary material, which is available to authorized users.

Diagnostic efficacy of endoscopic ultrasound-guided needle sampling for upper gastrointestinal subepithelial lesions: a meta-analysis

BACKGROUND

An increasing number of studies have been conducted on the use of endoscopic ultrasound (EUS)-guided needle sampling for upper gastrointestinal subepithelial lesions (SEL). However, reported diagnostic efficacy varies greatly.

OBJECTIVE

To summarize up current evidences on the diagnostic efficacy of EUS-guided needle sampling for upper GI SEL.

METHOD

A reproducible strategy was used to search four databases. Search results were evaluated for eligibility, and the quality of eligible studies was assessed by QUADAS-2. Pooled efficacy of EUS-guided needle sampling in upper GI SEL was calculated. Procedure-related complications, diagnostic errors, and independent factors related to a higher success rate were also recorded and analyzed.

RESULTS

Seventeen studies, comprising 978 attempts of EUS-guided needle sampling, were included in a meta-analysis. Pooled diagnostic rate of EUS-guided needle sampling was 59.9 %, with a heterogeneity I (2) of 55.2 %. Subgroup analysis showed no difference in diagnostic rate among fine needle aspiration (FNA), trucut needle biopsy (TCB), and fine needle biopsy (FNB), or among 19-, 22-, and 25-G needles. Subgroup analysis and meta-regression suggested that the cell block method might be correlated with a higher diagnostic rate. Few severe complications were reported. Diagnosis errors were rare.

CONCLUSION

EUS-guided needle sampling is a safe, but only moderately effective method for pathology diagnosis of upper GI SEL. Choice of FNA/TCB/FNB, or 19 G/22 G/25 G does not seem to alter the overall diagnostic rate.

Colorectal Subepithelial Lesions

Most of subepithelial lesion (SEL) being identified was accidentally discovered as small bulging lesion covered with normal mucosa from endoscopic screening. The type of treatment and prognosis vary depending on the type of tumor, it would be crucial to perform an accurate differential diagnosis. Since the differentiation of SEL relied on the indirect findings observed from the mucosal surface using an endoscopy only in the past, it was able to confirm the presence of lesion only but difficult to identify complex detailed nature of the lesion. However, after the endoscopic ultrasonography (EUS) was introduced, it became possible to identify extrinsic compression, and size of intramural tumors, internal properties and contour so that it gets possible to have differential diagnosis of lesions and prediction on the lesion whether it is malignant or benign. In addition, the use of EUS-guided fine needle aspiration and EUS-guided core biopsy made it possible to make histological differential diagnosis. This study intended to investigate endoscopic and EUS findings, histological diagnosis, treatment regimen and impression of colorectal SELs.

Gastric subepithelial lesion complicated with abscess: Case report and literature review

Gastric abscess is a localized pyogenic inflammation of the gastric wall, which is a rare form of suppurative gastritis. The rarity of gastric abscess may be associated with the difficulty of early diagnosis and high mortality as a result. In general, subepithelial lesions (SELs) of the stomach are incidentally detected during the course of upper endoscopy without specific clinical symptoms and signs. However, some gastric SELs present rarely as a form of hemorrhage, obstruction, perforation, and abscess. Here we report a 45-year-old man with gastric SEL presenting as a gastric abscess, which was diagnosed as an ectopic pancreas of the stomach, along with a review of the literature. Although gastric SEL presenting as an abscess is known as a serious and life-threatening lesion, the patient made a complete recovery through surgical resection as well as medical treatment.

Esophageal subepithelial lesion diagnosed as malignant gastrointestinal neuroectodermal tumor

A 21-year-old male visited our hospital with a complaint of aggravating dysphagia and odynophagia for a few days. Esophagogastroduodenoscopy showed huge bulging mucosa with an intact surface causing luminal narrowing at 35 cm from the incisor teeth. Endoscopic ultrasonography showed an about 35 mm sized irregular margined in-homogenous hypoechoic lesion with an obscure layer of origin. Endoscopic ultrasonography fine needle aspiration revealed spindle cell proliferation without immunoreactivity for CD117, SMA, and cytokeratin. The patient underwent excision of the subepithelial lesion at the distal esophagus. On pathologic examination of the specimen, the tumor was composed of short fascicles of oval to spindle cells with eosinophilic and clear cytoplasm and vesicular nuclei. The tumor cells were positive for S-100 and SOX10 and negative for CD117, SMA, HMB-45, melan-A, cytokeratin, and CD99. The split-apart signal was detected in EWSR1 on FISH, suggesting a malignant gastrointestinal neuroectodermal tumor. At the time of writing, the patient is on radiation therapy at the operated site of esophagus and doing well, with no recurrence for three months. Malignant gastrointestinal neuroectodermal tumor is a rare gastrointestinal tumor with features of clear cell sarcoma, without melanocytic differentiation, and shows a poor prognosis. This is the first reported case of malignant gastrointestinal neuroectodermal tumor arising as subepithelial lesion in the esophagus.

Forward-viewing linear echoendoscope: a new option in the endoscopic ultrasound armamentarium (with video)

The forward-viewing linear echoendoscope (FV-EUS) has been developed with the aim of overcoming limitations of standard curved linear-array echoendoscopes (CLA-EUS) and to further expand interventional applications of EUS. The main characteristic of the FV-EUS is a shifting in the orientation of both endoscopic and ultrasound views from oblique to forward, with the exit of the working channel at the tip of the instrument. This allows exit of the devices parallel to the longitudinal axis of the endoscope, thus resulting in a more direct and stable access to the lesion while increasing the precision and force applied to the target. Accumulating evidence has shown that the FV-EUS can be used instead of the standard CLA-EUS scope for routine fine needle aspiration, with extremely good performance for subepithelial lesions and for difficult to reach locations. Several areas of use of this echoendoscope are yet to be better defined, such as its potential for therapeutic and interventional procedures, as well as for natural orifice transluminal endoscopic surgery. The current report provides an updated overview of the available evidence for both diagnostic and interventional uses of the FV-EUS.

Concordance of endoscopic ultrasonography-guided fine needle aspiration diagnosis with the final diagnosis in subepithelial lesions

Background/Aims

In this study we aimed to determine the rate of concordance of endoscopic ultrasonography (EUS)-guided fine needle aspiration (FNA) diagnosis with the final diagnosis obtained by surgery or endoscopic resection and follow-up in upper gastrointestinal subepithelial lesions.

Methods

We retrospectively studied patients with subepithelial lesions who underwent EUS at our center from 2007 to 2011.

Results

We had a final diagnosis in 67 patients (mean age±SD, 51.23±12.48 years; 23 [34.3%] female, 44 [65.6%] male). EUS-FNA was performed in all of the patients. On-site pathology was not performed. In nine of the patients, the obtained material which was obtained was insufficient. The cytologic examination was benign in 31 and malignant in 27 of the patients. Based on the final diagnosis, the EUS-FNA had a sensitivity of 96%, a specificity of 100%, and a diagnostic yield of 85%.

Conclusions

The diagnostic yield of EUS-FNA, in the absence of the on-site cytopathologist, is feasible for the diagnosis of subepithelial lesions of the upper gastrointestinal system.

Endoscopic ultrasound, where are we now in 2012?

Topics related with endoscopic ultrasound (EUS) made up considerable portion among many invited lectures presented in International Digestive Endoscopy Network 2012 meeting. While the scientific programs were divided into the fields of upper gastrointestinal (UGI), lower gastrointestinal, and pancreato-biliary (PB) categories, UGI and PB parts mainly dealt with EUS related issues. EUS diagnosis in subepithelial lesions, estimation of the invasion depth of early gastrointestinal cancers with EUS, and usefulness of EUS in esophageal varices were discussed in UGI sessions. In the PB part, pancreatic cystic lesions, EUS-guided biliopancreatic drainage, EUS-guided tissue acquisition, and improvement of diagnostic yield in indeterminate biliary lesions by using intraductal ultrasound were discussed. Advanced techniques such as contrast-enhanced EUS, EUS elastography and forward-viewing echoendoscopy were also discussed. In this paper, I focused mainly on topics of UGI and briefly mentioned about advanced EUS techniques since more EUS related papers by other invited speakers were presented afterwards.

A case of endoscopic resection of a colonic semipedunculated leiomyoma

During colonoscopic examination, epithelial lesions, such as adenomatous polyps, are frequently encountered, unlike subepithelial lesions, such as leiomyomas, which are uncommon. A colonic leiomyoma is a rare tumor, originating either from the mucularis mucosa or from the proper muscle, and accounts for only 3% of all gastrointestinal leiomyomas. Colonic leiomyomas are usually benign and asymptomatic. However, they can sometimes cause symptoms, ie, abdominal pain, intestinal obstruction, hemorrhage, and perforation. The traditional management option for a colonic leiomyoma is surgical resection. Recently, with the development of endoscopy devices and techniques, the endoscopic resection has been considered as an alternative treatment option. We experienced a patient with a leiomyoma that was diagnosed during colonoscopy. The leiomyoma was resected endoscopically without complication. We report this case with a review of the literature.

Diagnostic yield of tissue sampling using a bite-on-bite technique for incidental subepithelial lesions

BACKGROUND/AIMS

Techniques for endoscopic evaluation of gastrointestinal subepithelial lesions include conventional endoscopy, jumbo biopsy, endoscopic ultrasonogrphy (EUS), EUS-guided fine needle aspiration, and endoscopic submucosal resection. However, these procedures have many limitations, such as low diagnostic yields and high complication rates. We therefore evaluated the diagnostic yield for tissue sampling of incidental subepithelial lesions using the bite-on-bite technique.

METHODS

One hundred and forty subepithelial lesions were found in 129 patients during conventional diagnostic esophagogastroduodenoscopy by one examiner from October 2003 to November 2004. Bite-on-bite biopsies with conventional-sized forceps were taken from 36 patients having 37 lesions that did not appear to be hypervascular or to have a thick overlying epithelium. Two to eight bites were performed to obtain submucosal tissue for one lesion.

RESULTS

The bite-on-bite technique was diagnostic in 14 of the 37 lesions (38%). Blood oozing for more than 30 seconds occurred in five cases, but was easily controlled by epinephrine injection (2 cases) or hemoclip (3 cases). The diagnostic yield tended to be higher in the esophagus than in the stomach and duodenum (54% vs. 28%, p=0.109).

CONCLUSIONS

The bite-on-bite technique for subepithelial lesions is an effective and safe method in selected cases. This technique may be useful for incidental subepithelial lesions, especially those of the esophagus, except for ones with a high risk of bleeding or thick overlying epithelium.