Efficacy and safety of one-step knife compared to conventional insulated-tip knife for endoscopic submucosal dissection: a preliminary study with prospective data collection and retrospective review.

BACKGROUND: Endoscopic submucosal dissection (ESD) is not as tiresome as gastrectomy, but it is a time-consuming procedure. One-step knife (OSK) is a novel knife that combines a knife for ESD and an injection needle into one sheath. In this study, we aimed to compare the insulated tip type of OSK and conventional knife (CK) in terms of procedure time and complication rate. METHODS: Medical records of patients with ESD using CK between February and September 2020 were retrospectively reviewed. Subsequently, data from patients who underwent ESD using OSK by September 2021 were prospectively collected. Total procedure time, procedure time by location and complication rate in the OSK and CK group were compared. RESULTS: In the study period, a total of 203 patients (OSK, 102 patients; CK, 101 patients) were analyzed. On multivariate analysis, using CK, body location, resection size ≥ 40 mm, and submucosal fibrosis were associated with longer procedure time. The total procedure time was statistically significantly reduced in the OSK group (median 11 vs. 17 min, p < 0.01). The procedure time for each location was more reduced in the body (median 14 vs. 19 min p < 0.01) than the antrum (median 10 vs. 14 min, p = 0.01) in the OSK group. There was no significant difference in post-ESD bleeding and perforation in the two groups (3.9 vs. 3.9%, p = 0.99 and 1.0 vs. 2.0%, p = 0.56). CONCLUSIONS: OSK significantly reduced the total procedure time of ESD. OSK could be an effective and safe knife for gastric ESD, especially for body lesions.

Comparison of biannual and annual endoscopic gastric cancer surveillance after endoscopic resection.

BACKGROUND: Patients who received endoscopic resection (ER) for early gastric cancer (EGC) or high-grade dysplasia (HGD) are at high risk for the subsequent development of metachronous gastric cancer (MGC). This study aims to compare the detection rate and stage of MGC between biannual and annual endoscopic surveillance after ER of EGC or HGD. METHODS: From September 2009 to August 2019, 859 patients who underwent ER for the treatment of EGC or HGD were analyzed, retrospectively. Patients received endoscopic surveillance twice a year (high-intensity group) or annually (low-intensity group) for 3 years. RESULTS: A total of 521 patients were enrolled in this study (267 patients in the high-intensity group and 254 patients in the low-intensity group). During a mean follow-up of 5.3 ± 1.6 years, MGCs were found in 27 patients (16.9%) in the high-intensity group and 18 patients (7.1%) in the low-intensity group (P = 0.219). In patients with moderate to severe atrophy (Kimura-Takemoto grade C3 ~ O3), detection rates of MGC during 3 years from were 8.4% (16/191) and 2.2% (4/186), respectively (P = 0.007). Forty-four patients who received treatment for MGC, including endoscopic or surgical resection, were stage IA. Only one patient in the low-intensity group was diagnosed as stage IIIA advanced gastric cancer. CONCLUSIONS: There was no significant difference in the detection rate of MGC between biannual and annual endoscopic surveillance after ER of EGC or HGD. However, biannual surveillance showed a higher detection rate during the first 3 years, especially for patients with moderate to severe gastric atrophy.

Endoscopic visualization of graft status in patients with pancreas transplantation.

BACKGROUND: Enteric drainage into the recipient duodenum in pancreas transplantation (PT) can identify the graft duodenum by endoscopy. This study aimed to identify the characteristic endoscopic findings associated with graft failure or acute rejection in patients with PT. METHODS: We reviewed the medical records of patients who underwent PT with duodenoduodenostomy (DD) between January 2015 and August 2019. During this period, there were 44 PTs with DD in 42 patients; 122 endoscopies were performed and analyzed. RESULTS: Overall, pancreatic graft survival was 82% at a mean follow-up of 27 months (range 6-55 months). There were 8 graft failures and 10 acute rejections. In all 8 graft failures, a deep ulcer covered with fibrinous exudates of the graft duodenum was confirmed on endoscopy. Diffuse erythema inside the graft duodenum was observed in 8 of 10 acute rejections. The factors associated with acute rejection were elevated serum lipase level (OR 8.5, p = 0.02) and diffuse erythema inside the graft duodenum on endoscopy (OR 20.5, p < 0.01) in multivariate analysis. CONCLUSIONS: In PT with DD patients, graft failure can be visualized by endoscopy, and diffuse erythema inside the graft duodenum may be a finding of acute rejection.

Long-term outcomes and surveillance timing of patients with large non-pedunculated colorectal polyps with histologically incomplete resection in endoscopic resection.

BACKGROUND: Histologically incomplete resection of large colorectal polyps is frequently encountered; however, the long-term outcomes or surveillance timing is not well known. We evaluated the incidence rate and time of recurrence of these cases during a long-term follow-up. METHODS: We performed a retrospective analysis of patients who underwent endoscopic resection for large (≥10 mm in size) non-pedunculated colorectal polyps at a tertiary academic hospital. Patients who had positive or indeterminate lateral margin in the histology and underwent completed surveillance colonoscopy first at 3-12 months and finally at ≥2 years after initial resection were included. RESULTS: Of 169 polyps (148 patients), 37 (21.9%) and 132 (78.1%) polyps had positive and indeterminate lateral margins, respectively. The median time intervals of the first and last surveillance from the initial resection were 6 (3-12) and 48 (24-114) months, respectively. The recurrence rate was 9.5% (16/169) during follow-up, and the mean time to recurrence was 31.9 months. Thirteen (81.3%) polyps recurred after ≥12 months. Most (14/16, 87.5%) recurrent polyps were benign, and 2 cases had advanced cancer. The only factor that was significantly associated with recurrence in the univariate and multivariate analyses was ≥3 piecemeal resections (odds ratio in the multivariate analysis, 16.92; 95% CI, 1.19-241.81; p = 0.037). CONCLUSION: During the long-term follow-up, the only factor that was significantly associated with recurrence was ≥3 piecemeal resections, and most recurrences occurred after ≥12 months. Thus, a histologically incomplete resection with ≤2 piecemeal resections and no findings of suspected submucosal cancer may be considered as complete resection, and these patients may undergo first surveillance colonoscopy after 1-2 years.

Factors associated with conversion to snare resection during gastric endoscopic submucosal dissection.

BACKGROUND AND AIMS: Although gastric endoscopic submucosal dissection (ESD) achieves a higher en-bloc resection rate compared to that with endoscopic mucosal resection (EMR) for gastric epithelial tumors, the higher complication rate and the longer procedure time are obstacles for its widespread use. Rescue EMR may be a valuable treatment option during difficult ESD procedures. We have aimed to identify the clinical outcomes and associated factors of rescue EMR during ESD. PATIENTS AND METHODS: The medical records of patients who underwent ESD between January 2009 and February 2016 were reviewed. The clinical outcomes of rescue EMR during ESD and associated factors with rescue EMR were evaluated. RESULTS: A total of 1778 gastric epithelial lesions were enrolled. ESD without using a snare and rescue EMR were performed in 94.5% and 5.5% of patients, respectively. Lesion locations of mid-third [odd ratio (OR 4.470)], upper-third (OR 1.997), and submucosal fibrosis (OR 1.906) were the significant associated factors with rescue EMR. The en-bloc resection rate and complete resection rate of rescue EMR were lower than that of ESD (98.4% vs. 93.8% and 96.2% vs. 83.5%, respectively). Local recurrence rate was higher after rescue EMR than that after ESD (4.1% vs. 1.2%). Procedure-related complications and procedure time were not significantly different between the two groups. CONCLUSIONS: In a difficult ESD procedure, rescue EMR may be an alternative treatment option, especially for lesions located at the mid-to-upper third of the stomach, without increasing either the procedure time or the rate of complications.

Clinical outcomes of endoscopic submucosal dissection for lesions on the proximal location between remnant and entire stomach.

BACKGROUND: Tumors located on the proximal stomach are associated with a longer procedure time and lower en-block resection of endoscopic submucosal dissection (ESD). Additionally, it is more difficult to perform ESD for lesions after distal gastrectomy because of the narrow inner space. We aimed to evaluate the therapeutic outcomes of ESD for lesions on the remnant stomach compared with those on the upper third of the entire stomach. METHODS: A total of 135 patients with a neoplasm located on the proximal stomach who received ESD between Aug 2008 and Dec 2016 were enrolled. We retrospectively reviewed en-bloc resection rate, complete resection rate, and complication rate according to whether distal gastrectomy was performed. Clinical outcomes were compared among the 1:2 propensity-matched groups. RESULTS: Between the remnant stomach and entire stomach, the en-bloc [92% (23/25) and 92.0% (46/50), respectively; P = 1.000] and complete resection [84% (21/25) and 88.0 (44/50), respectively; P = 0.723] rates were not significantly different. In patients with lesions that indicated ESD, there was no significant difference in en-bloc and complete resection rates. In a multivariable analysis, submucosal fibrosis [odds ratio (OR) 5.9, 95% confidence interval (CI) 1.1-30.7] and submucosa invasive cancer (OR 10.1, 95% CI 1.4-74.3) were independent risk factors for incomplete resection. CONCLUSIONS: ESD is a feasible therapeutic option for lesions located on the proximal stomach regardless the operation history of distal gastrectomy. However, the complete resection rate decreases for lesions with submucosal fibrosis or the submucosa invasion.

Efficacy of preoperative colonoscopic tattooing with indocyanine green on lymph node harvest and factors associated with inadequate lymph node harvest in colorectal cancer.

Objective: Adequate lymph node harvest (LNH) in colorectal cancer is closely related to survival. This study aimed to evaluate the effect of preoperative colonoscopic tattooing (PCT) with indocyanine green (ICG) on adequate LNH in colorectal cancer. Materials and methods: A total of 1079 patients who underwent surgical resection for colorectal cancer were divided into two groups: a tattooing group and a non-tattooing group. The patients were retrospectively analyzed for the number and adequacy of LNH according to tumor locations and stages. Univariate and multivariate analysis for factors associated with adequate LNH were done. Results: There was no significant difference between the two groups in the number and adequacy of LNH according to tumor locations. However, T1 colorectal cancer in the tattooing group had significantly higher adequate LNH (91.6% vs 82.1%, OR 2.370, p = .048) and T1 and N0 rectal cancer in the tattooing group also had higher adequate LNH although there was no statistical significance (100% vs 82.4%, OR 12.088, p = .095; 96.9% vs 84.8%, OR 5.570, p = .099) when compared to the non-tattooing group. Male sex and T1 stage were significantly associated with inadequate LNH in multivariate analysis (OR 0.556 (95% CI 0.340-0.909), p = .019; OR 0.555 (95% CI 0.339-0.910), p = .019, respectively). Conclusion: PCT with ICG did not improve adequate LNH in colorectal cancer but effectively improved adequate LNH in early colorectal cancer. Male sex and early cancer were risk factors for inadequate LNH in colorectal cancer, so PCT is needed for adequate LNH in these patients.

Clinical outcomes of iatrogenic upper gastrointestinal endoscopic perforation: a 10-year study.

BACKGROUND: Upper gastrointestinal endoscopic examination is a relatively safe procedure; however, all endoscopic procedures are invasive and are associated with a risk of iatrogenic perforation. To evaluate clinical outcomes of iatrogenic upper gastrointestinal endoscopic perforation. Factors associated with surgical management or mortality were analyzed. METHODS: Between November 2008 and November 2018, the medical records of 149,792 upper gastrointestinal endoscopic procedures were evaluated. The mechanisms of perforations were categorized as electrocoagulation-induced or blunt trauma-induced injuries. The incidence and clinical outcomes of iatrogenic perforations based on the types of procedures performed were evaluated. RESULTS: Iatrogenic endoscopic perforations occurred in 28 cases (0.019%). Iatrogenic perforation-related mortality occurred in 3 patients. The iatrogenic perforation rate based on the types of procedures performed was as follows: diagnostic endoscopy = 0.002%, duodenal endoscopic mucosal resection = 0.9%, esophageal endoscopic submucosal dissection = 10.7%, gastric endoscopic submucosal dissection = 0.2%, endoscopic self-expandable metal stent insertion for malignant esophageal obstruction = 0.1%, duodenoscope-induced injury = 0.02%, endoscopic sphincterotomy = 0.08%, and ampullectomy = 6.8%. All electrocoagulation-induced perforations (n = 21) were managed successfully (15 cases of endoscopic closure, 5 cases treated conservatively, and 1 case treated surgically). Three patients died among those with blunt trauma-induced perforations (n = 7). The factors associated with surgical management or mortality were old age, poor performance status (Eastern Cooperative Oncology Group score ≥ 1), advanced malignancy, and blunt trauma. CONCLUSIONS: Most cases of electrocoagulation-induced iatrogenic perforations can be treated using endoscopic clips. If endoscopic closure fails for blunt trauma-induced perforations, prompt surgical management is mandatory.

Endoscopic submucosal dissection for gastric indefinite for neoplasia: which lesions should be resected?

BACKGROUND AND STUDY AIMS: The management plan for gastric indefinite for neoplasia is undetermined, and endoscopic forceps biopsy might be inconclusive in ascertaining whether a resection is required. This study aimed to evaluate the clinical outcomes of endoscopic submucosal dissection (ESD) for gastric indefinite for neoplasia and to identify the factors highly predictive of true neoplasia. PATIENTS AND METHODS: This retrospective study was conducted in a single, tertiary, referral hospital between November 2008 and December 2015. A total of 109 gastric indefinite for neoplasia lesions from endoscopic forceps biopsy that were resected by ESD were included in the study. The clinical outcomes and endoscopic factors for prediction of true neoplasia were analyzed. RESULTS: A total of 99 patients (90.8%) were diagnosed with definite neoplasia after ESD and were classified as category 3 (n = 42), category 4 (n = 50), and category 5 (n = 7) according to the revised Vienna classification. The mean age of the patients was 65.8 ± 9.8 years. The mean lesion size was 10.7 ± 6.1 mm. The patient population predominantly consisted of male patients (70.6%). The en bloc and complete endoscopic resection rates were 98.2% and 94.5%, respectively. Factors associated with true neoplastic lesions were male sex (odds ratio [OR] 8.596, p = 0.008) and lesion size ≥ 5 mm (OR 11.355, p = 0.003). Factors associated with category 4-5 were male sex (OR 3.165, p = 0.021) and erosive change (OR 2.841, p = 0.031). CONCLUSIONS: Endoscopic resection for indefinite for neoplasia with larger lesions size and erosive changes, especially in males, should be considered when possible.

Endoscopic predictive factors associated with local recurrence after gastric endoscopic submucosal dissection.

OBJECTIVE: Endoscopic submucosal dissection (ESD) has been accepted as the treatment of choice for gastric epithelial neoplasia. Endoscopic characteristics of the primary lesion and post-ESD scars may be informative to predict the possibility of local recurrence. METHODS: Between November 2008 and July 2015, a retrospective study was conducted in a single-tertiary referral hospital. Consecutive patients who underwent ESD for early gastric cancer (EGC) or high-grade dysplasia were analyzed to evaluate the incidence of local recurrence and associated endoscopic characteristics. RESULTS: A total of 639 lesions were analyzed. The rates of en-bloc and complete resection were 98.1% and 95.5%, respectively. A total of 15 local recurrent lesions were found (2.3%). The endoscopic findings of primary lesions associated with local recurrence were a lesion size ≥20 mm (odds ratio, OR, 4.408; 95% confidence interval, CI, 1.369-14.186, p = .013) and incomplete endoscopic resection (OR 17.059, 95% CI 4.887-59.551, p < .001). During follow-up endoscopic examinations, atypical scar findings (non-flat morphology, erythematous color change and uneven surface pattern) were significant endoscopic findings to predict local recurrence. Local recurrence was absent for ESD scars with even-flat morphology without erythema. CONCLUSION: Lesions with larger size (≥ 20 mm) and incompletely resected lesions had higher risk of local recurrence. Endoscopic forceps biopsy is unnecessary for even-flat ESD scar without erythematous changes.

Endoscopic submucosal dissection of gastric neoplasms using a snare tip.

BACKGROUND: Endoscopic submucosal dissection (ESD) enables the complete removal of gastric lesions regardless of tumor size. ESD is typically performed using one of several available electrocautery knives and endoscopic mucosal resection (EMR) is performed using a diathermic snare. We aimed to investigate the clinical outcomes and complications in patients in whom a snare tip was used for ESD. MATERIALS AND METHODS: We retrospectively evaluated the medical records of 30 patients who underwent removal of a gastric lesion using a snare tip by ESD or hybrid ESD (ESD with snaring). For hybrid ESD, snaring was performed after an adequate submucosal dissection. The clinical outcomes according to the endoscopic procedure performed were evaluated. RESULTS: ESD was performed in 12 patients and hybrid ESD was performed in 26 patients. Overall en-bloc and complete resection rates were both 97.4%. There was one case where piece-meal resection was performed in the hybrid ESD group. There were no procedure related complications such as perforation or bleeding. The mean specimen size was 2.8 ± 0.6 cm in the ESD group and 2.3 ± 0.5 cm in the hybrid ESD group (p = .031). The mean procedure time did not differ between the two methods (12.8 min in ESD and 9.7 min in hybrid ESD, p = .060). CONCLUSIONS: The snare tip can be used as an electrocautery knife to incise the mucosa and dissect the submucosa during removal of a gastric lesion.

Evaluation of valve function in antireflux biliary metal stents.

BACKGROUND: To overcome duodenobiliary reflux induced by biliary stents, antireflux valve (ARV) biliary stents have been developed and showed improvement in stent patency. However, negative study results have also been reported because stent patency may be decreased by the malfunction of ARV itself. Given such mixed results, the true efficacy of ARV remains unknown and the mechanism of its dysfunction needs to be clearly elucidated. The aim of this study was to investigate the exact mechanism of ARV dysfunction using in vitro phantom models. METHODS: Two experimental models were designed to evaluate two important environmental factors suspected to cause ARV malfunction, i.e. bile flow and pH. Three types of ARV metal stents from different companies were used for the experiments: a funnel type ARV, a windsock type ARV, and a wine glass-shaped ARV. Ten stents of each type were tested (five stents in the bile flow phantom model, and another five stents in the duodenal pH environmental model). To determine ARV malfunction, ARV-induced flow resistance was measured using a custom-made testing device. All stents from the two models were removed every 2 weeks for 12 weeks after stent insertion and were evaluated on morphological and functional changes of the ARV. RESULTS: Only ARV of wine glass-shaped ARV was morphologically changed due to silicone bond detachment in the bile flow model. All types of ARV were morphologically changed in the pH model. The morphological changes of ARV influenced the flow resistance. The antegrade pressure gradients were increased over time in the pH model (p < 0.05). CONCLUSIONS: Morphological change of the ARVs may induce dysfunction of ARV metal stents, which is mainly due to duodenal pH environment. In the future, development of new ARV that is not affected by duodenal environmental factors can be expected to improve stent patency.

Predictors of upstage diagnosis after endoscopic resection of gastric low-grade dysplasia.

BACKGROUND: The optimal management of precursor lesions such as gastric low-grade dysplasia is crucial in order to improve gastric cancer-related mortality. However, there are no universally accepted management guidelines regarding which lesions should be resected or should be monitored by follow-up visits. PATIENTS AND METHODS: We retrospectively analyzed data from 1006 gastric low-grade dysplasia lesions that had been resected via endoscopic submucosal dissection. We also evaluated the endoscopic risk factors associated with upstage diagnosis from low-grade dysplasia to high-grade dysplasia or gastric cancer. RESULTS: The mean age of our patients was 63.7 ± 9.1 years and 70.3% of our study population included men. The predominant location and gross type of lesions was the lower third of the stomach (78.6%) and the elevated type (57.8%), respectively. The rates of pathological concordance, upstage, and downstage diagnosis were 85.3, 12.1, and 2.6%, respectively. Multivariate analysis, after adjusting for age and sex, showed that a lesion size ≥ 10 mm (Odds ratio [OR] 2.231; p = 0.003), erythema (OR 7.315; p < 0.001), nodularity (OR 5.589; p < 0.001), depression (OR 3.024; p = 0.002), and erosion (OR 7.680; p < 0.001) were all factors significantly associated with upstage diagnosis. Furthermore, an increasing number of risk factors was associated with an increasing frequency of upstage diagnosis; if there were no risk factors, then there was no upstage diagnosis. CONCLUSIONS: This study identified several risk factors that were significantly associated with the upstage diagnosis of gastric low-grade dysplasia: lesion size ≥ 10 mm and a variety of surface changes (erythema, nodularity, depression, and erosion). Our data indicate that if there is no evidence of these endoscopic risk factors, then regular follow-up may be considered, according to the patient's combined comorbid conditions.

Preoperative predictors of beyond endoscopic submucosal dissection indication or lymphovascular invasion in endoscopic resection for early gastric cancer.

BACKGROUND: To successfully resect early gastric cancer (EGC), prediction of lymph node metastasis is essential. Beyond endoscopic submucosal dissection (ESD) indication or lymphovascular invasion (LVI) are known risk factors associated with lymph node metastasis. However, accurate prediction of tumor invasion depth or LVI is impossible before endoscopic resection even when endoscopic ultrasound is used. The aim of this study was to identify the predictive factors associated with beyond ESD indication or LVI after ESD for EGC. METHODS: Between Jan 2011 and Feb 2015, 532 lesions from 506 patients who received ESD for EGCs were included. We reviewed the data of patients diagnosed as EGCs without ulceration or those smaller than 3 cm with ulceration. RESULTS: The incidence of EGCs found to be beyond expanded ESD indications or present of LVI after ESD was 11.1% (59/532). On multivariable analysis, endoscopic features of SM invasion, surface color changes, and elevated lesions were associated with beyond ESD indication or LVI. In particular, submucosal (SM) invasive features such as SM tumor-like marginal elevation [odds ratio (OR) 17.2; 95% confidence interval (CI) 2.0-146.7], fusion of convergent folds (OR 12.9; 95% CI 3.9-42.1), irregular surface (OR 17.8; 95% CI 5.6-56.8), and discoloration of the tumor surface (OR 16.1; 95% CI 2.4-105.9) were significant risk factors for beyond ESD indication or LVI. CONCLUSIONS: The decision to proceed with endoscopic resection for EGCs with endoscopic features of SM invasion, surface color changes, or elevated forms must be made cautiously.

Enhanced Photosensing and Photodynamic Treatment of Colon Cancer Cells Using Methoxy Poly(ethylene glycol)-Conjugated Chlorin e6.

Nanophotosensitizer composed of methoxy poly(ethylene glycol) (MePEG) and chlorin e6 (Ce6) (abbreviated as Pe6) was synthesized for efficient delivery of Ce6 to the colon cancer cells. Pe6 nanophotosensitizer has small diameter less than 100 nm with spherical shape and core-shell structure. They were activated in aqueous solution while Ce6 was quenched due to its poor aqueous solubility. They showed no intrinsic cytotoxicity against normal cells and colon cancer cells. Pe6 nanophotosensitizers showed enhanced cellular uptake, phototoxicity, and reactive oxygen species (ROS) generation at in vitro cell culture experiment. Furthermore, they showed improved tumor tissue penetration and accumulation in vivo animal studies. We suggested Pe6 nanophotosensitizers as an ideal candidate for PDT of colon cancer.

Direct endoscopic biopsy for subepithelial tumor larger than 20 mm after removal of overlying mucosa.

OBJECTIVE: An accurate diagnosis of a subepithelial tumor (SET) using endoscopic ultrasound (EUS) without tissue acquisition is difficult. Treatment plan for a SET may be influenced by endoscopic tissue diagnosis. We aimed to clarify the clinical outcomes of direct endoscopic biopsy for SET after removal of the overlying mucosa. METHODS: We evaluated the medical records of 15 patients. All patients underwent direct endoscopic biopsy for a SET larger than 20 mm (involving proper muscle layer) after removal of the overlying mucosa. The rate of achieving an accurate diagnosis and the treatment decision after the procedure were evaluated. RESULTS: The patients' mean age was 55.1 ± 14.7 years. The patient population predominantly comprised men (9/15, 60%). The mean tumor size was 24.3 ± 7.8 mm. The mean biopsy number was 3.5 ± 1.7. No major complications occurred with the procedure. The mean procedure time was 15 ± 7.4 min. An accurate diagnosis was achieved in 93.3% of patients (14/15). The main pathological diagnoses after direct endoscopic SET biopsy were leiomyoma (33.3%, 5/15) and ectopic pancreas (33.3%, 5/15) followed by gastrointestinal stromal tumor (GIST) (13.3%, 2/15) and schwannoma (13.3%, 2/15). The treatment plan was influenced by the result of biopsy in 80% of patients (9/15), and unnecessary surgical resection was avoided. CONCLUSIONS: Direct endoscopic SET biopsy after removal of the overlying mucosa using an endoscopic conventional snare was a useful diagnostic tool with high diagnostic accuracy and low risk of complications.

Factors associated with the efficacy of miniprobe endoscopic ultrasonography after conventional endoscopy for the prediction of invasion depth of early gastric cancer.

BACKGROUND: This study aimed to compare the accuracy of conventional endoscopy (CE) and endoscopic ultrasonography (EUS) to predict tumor invasion depth and to determine factors associated with higher accuracy of additional miniprobe EUS after CE. METHODS: Between May 2009 and February 2015, 273 lesions in 266 patients were subjected to miniprobe EUS after CE and curative treatment for well-to-moderately differentiated early gastric cancer (EGC). We reviewed preoperative CE and EUS findings and compared them to the pathologic findings. RESULTS: The accuracy of CE and EUS to estimate the invasion depth of EGCs was 78.8% (215/273) and 83.9% (229/273) (p = .124), respectively. Using multivariate analysis, irregular depressed surface (odds ratio [OR] 8.11; 95% confidence interval [CI]: 2.79-23.53), fold change (OR 7.22; 95% CI: 2.33-22.38), size >2 cm (OR 2.72; 95% CI: 1.15-6.42) and ulcer scar (OR 2.64; 95% CI: 1.07-6.49) were associated with the higher accuracy of EUS than that of CE. CONCLUSIONS: Routine assessment using miniprobe EUS did not increase the accuracy of predicting invasion depth, compared to CE. However, EUS could be helpful in the treatment decision-making process for EGCs with lesions having irregular surfaces, fold change, size >2 cm, or ulcer scar.

Clinical outcomes of endoscopic submucosa dissection for high-grade dysplasia from endoscopic forceps biopsy.

BACKGROUND AND STUDY AIMS: Although the Vienna Classification recommends endoscopic resection for gastric high-grade dysplasia (HGD), many resected lesions are diagnosed as gastric cancer after endoscopic resection. This study aims to evaluate the clinical outcomes of gastric HGD identified by endoscopic forceps biopsy (EFB) after endoscopic submucosal dissection (ESD) and factors associated with discrepant results. PATIENTS AND METHODS: From December 2008 to July 2015, a total of 427 lesions diagnosed as initial HGD by EFB were enrolled. The rate of early gastric cancer (EGC) and factors predicting diagnosis upgrade were analyzed retrospectively. RESULTS: Tumors ranged between 2 and 65 mm in size (median 12.59). En bloc and complete resection rates were 97.4 and 95.3%, respectively. The diagnostic discrepancy rate was 76.3%. Upgrade and downgrade rates of pathological diagnoses were 66.5 and 9.8%, respectively. Central depression (OR 4.151), nodular surface (OR 5.582), surface redness (OR 2.926), lesion location (upper third of the stomach) (OR 3.894), and tumor size ≥10 mm (OR 2.287) were significantly associated with EGC. Nodular surface (OR 2.746), submucosal fibrosis (OR 3.958), lesion location (upper third of the stomach) (OR 6.652), and tumor size ≥10 mm (OR 4.935) significantly predicted invasive submucosal cancer. CONCLUSIONS: Central depression, nodular surface, surface redness, lesion location, large tumor size, and submucosal fibrosis were associated with EGC or submucosal cancer. Caution must be used in treating lesions with these features with ESD.

Clinical features of negative pathologic results after gastric endoscopic submucosal dissection.

BACKGROUND: Endoscopic submucosal dissection (ESD) is widely used for the treatment of gastric superficial neoplasms. Negative pathologic results after ESD can confuse the endoscopists and patients. The aim of this study was to evaluate the reasons for and the factors associated with negative pathologic results after ESD. PATIENTS AND METHODS: From December 2008 to July 2015, a total of 1379 lesions diagnosed as definite dysplasia or adenocarcinoma by endoscopic forceps biopsy (EFB) were removed with an ESD procedure. The initial endoscopic and pathologic findings were analyzed. RESULTS: The incidence of negative pathology after ESD was 2.0 % (28/1379). Compared with positive pathologic lesions, negative pathologic lesions were smaller and had less surface area (P < 0.001). The reasons for negative pathologic lesions after ESD were complete removal by EFB (n = 20), over-estimations of the EFB specimen (n = 5), and different ESD site (n = 3). CONCLUSION: Small tumor size and surface area are associated with negative pathologic results after ESD. When negative pathologic results are reported after ESD, we should review the previous endoscopic biopsy tissue specimen and compare the previous EFB site to the ESD site. Thereafter, regular endoscopic examination of the lesion is needed.

Risk factors associated with difficult gastric endoscopic submucosal dissection: predicting difficult ESD.

BACKGROUND AND STUDY AIM: Endoscopic submucosal dissection (ESD) is a widely accepted treatment for superficial gastric neoplasms. Difficult ESD can lead to complications, such as bleeding and perforation. To predict difficult ESD procedures, we analyzed the factors associated with difficult ESD. PATIENTS AND METHODS: The medical records of 1052 ESD procedures were retrospectively reviewed. Difficult ESD was defined by any one of three end points: longer procedure time (≥60 min), piecemeal resection, incomplete (R1) resection, or gastric wall perforation. To determine the factors associated with difficult ESD, clinical and pathologic features and endoscopic findings were analyzed. RESULTS: The rates of en bloc resection and curative (R0) resection were 93.3 and 92.4 %, respectively. The mean procedure time was 27.7 ± 16.7 min. After multivariate analysis, larger tumor size (≥20 mm) was an independent risk factor for longer procedure time (OR 4.1, P < 0.001), for piecemeal resection (OR 2.3, P = 0.003) and incomplete (R1) resection (OR 2.1, P = 0.005). Location of the lesion (upper third) was an independent risk factor for longer procedure time (OR 5.8, P < 0.001), for piecemeal resection (OR 4.1, P < 0.001) and incomplete (R1) resection (OR 4.5, P < 0.001). Submucosal fibrosis was an independent risk factor for longer procedure time (OR 9.7, P < 0.001), for piecemeal resection (OR 2.4, P < 0.001) and incomplete (R1) resection (OR 2.6, P < 0.001). Finally, submucosal invasive gastric cancer was an independent risk factor for piecemeal resection (OR 2.6, P = 0.008), for perforation (OR 19.3, P = 0.001) and for incomplete (R1) resection (OR 2.7, P = 0.001). CONCLUSIONS: Difficult ESD procedures are a function of the lesion size and location, submucosal fibrosis, and submucosal invasive cancer. When a difficult ESD procedure is expected, appropriate preparations should be considered, including consultation with more experienced endoscopists.