Multiple foci of dilated vessels as a new predictor of metachronous esophageal cancer

OBJECTIVES

Prediction of the risk of esophageal squamous cell carcinoma (SCC) by endoscopic findings without iodine staining, which is irritating to the esophagus, would be beneficial. In a previous retrospective study, we found that multiple foci of dilated vascular areas (MDV) of the esophageal mucosa, seen in narrow-band imaging (NBI)/blue laser imaging (BLI), are associated with iodine-unstained lesions and, thus, may be a predictor of esophageal SCC. This prospective study aimed to investigate the association between MDV and metachronous esophageal SCC.

METHODS

Patients with a history of endoscopic resection for esophageal SCC were included in the study. First, evaluation of the MDV using NBI or BLI was conducted during the initial endoscopy. The patients were then monitored for metachronous esophageal SCC by endoscopic surveillance. The association between the number of MDV and incidence of metachronous esophageal SCC was investigated.

RESULTS

From February 2018 to May 2019, 206 patients were enrolled and 201 patients were included in the analysis. Patients were followed up until October 2022. The median (interquartile range) endoscopic follow-up period was 1260 (1105-1348) days. The incidence of metachronous esophageal SCC at 2 years was 7.1% in patients with MDV ≤4 and 13.9% in patients with MDV ≥5 (P < 0.01). In the multivariate analysis, MDV was an independent predictor of metachronous esophageal SCC, with an odds ratio (95% confidence interval) of 2.37 (1.06-5.31).

CONCLUSION

Multiple foci of dilated vascular area is a useful predictor for stratifying the risk of metachronous esophageal SCC.

Endoscopic landmarks corresponding to anatomical landmarks for esophageal subsite classification

Objectives

Individual treatment strategies for esophageal cancer have been investigated based on the anatomical subsite classification. Accurate subsite classification based on these anatomical landmarks is thus important. We investigated the suitability of the existing endoscopic classification and explored alternative landmarks for esophageal subsite classification.

Methods

Patients who received endoscopic ultrasonography (and computed tomography scans for surveillance of esophageal cancer treatment or esophageal submucosal tumors were included. Distances between anatomical landmarks, including the inferior cricoid cartilage border, superior border of the sternum, and tracheal bifurcation, were measured using a combination of endoscopic ultrasonography, computed tomography, and other information.

Results

The mean (standard deviation) distances from the superior incisor dentition to the pharynx-esophagus, cervical-upper thoracic esophagus, and upper-middle thoracic esophagus boundaries were 16.9 (1.7), 21.7 (1.9), and 29.0 (1.9) cm, respectively. However, variances in the differences between the mean and individual distances were large (2.8, 3.4, and 3.7, respectively), mainly because of differences in body height. However, variances in the differences between individual distances and novel endoscopic landmarks, including the lower end of the pyriform sinus and lower end of compression of the left main bronchus, were lower (1.7, 1.2, and 0.6, respectively).

Conclusions

Existing indicators of esophageal subsite boundaries were not consistent with anatomical boundaries. Modification of the distance from the superior incisor dentition based on average distances from anatomical landmarks or the use of alternative endoscopic landmarks is recommended to provide more suitable anatomical boundaries.

Predictors of technical difficulty for trainees in esophageal endoscopic submucosal dissection

BACKGROUND

Esophageal endoscopic submucosal dissection (ESD) is technically challenging, especially for trainees, and requires a safe training system. This study aimed to identify predictors of technical difficulty facing trainees performing esophageal ESD to establish such system.

METHODS

This was a single-center retrospective study of patients with esophageal cancer who underwent ESD performed by trainees between January 2010 and August 2022. Technical difficulties were defined as muscularis propria exposure and long procedure time (≥ 90 min). Factors associated with these technical difficulties were investigated.

RESULTS

A total of 798 lesions in 721 patients were evaluated. Muscularis propria exposure occurred in 298 lesions (37.3%), including 10 perforations (1.3%). The procedure time was ≥ 90 min in 134 lesions (16.8%). In the multivariate analysis, tumor size ≥ 20 mm, tumors ≥ 1/2 of the circumference, and those close to previous treatment scars significantly increased the incidence of both difficulties, whereas tumors in the upper esophagus significantly decreased this incidence. Furthermore, female sex and tumors in the left wall were independent predictors of muscularis propria exposure, and elevated morphology was an independent predictor of long procedure time. Muscularis propria exposure and long procedure time occurred in more than half of the cases with three or more predictors of each difficulty.

CONCLUSIONS

Large tumors and tumors close to previous treatment scars increase technical difficulties for trainees in esophageal ESD. Conversely, tumors in the upper esophagus reduce these difficulties. These results enable us to predict the difficulty level preoperatively and select appropriate cases in stepwise training.

Endoscopic features of gastric neuroendocrine carcinoma

BACKGROUND AND AIM

The endoscopic features of gastric neuroendocrine carcinoma (G-NEC) have not been clarified; therefore, they were investigated in relation to clinicopathological findings.

METHODS

Consecutive patients with G-NECs who had undergone endoscopic or surgical resection at our institution between January 2005 and March 2022 were included in this retrospective study. The endoscopic and clinicopathological findings of the lesions were analyzed to provide information of diagnostic value. In addition, cases of gastric neuroendocrine tumor (G-NET) and common-type gastric adenocarcinoma treated in the same study period were identified to compare the endoscopic findings between each G-NEC versus G-NET, and G-NEC versus common-type gastric adenocarcinoma. Patients with common-type gastric adenocarcinoma were matched for age, sex, tumor size, and depth of tumor invasion in 1:3 ratio.

RESULTS

Among 15 patients with 15 G-NECs, submucosal tumor-like marginal elevation (87%), adherent white coat (67%), and ulceration with a distinct border (60%) were characteristic endoscopic findings in white-light images. Magnifying narrow-band imaging endoscopy revealed an absent microsurface (MS) pattern plus disrupted irregular microvessel (MV) in five (71%) of seven cases with evaluable MS and MV patterns. The area with an absent MS pattern plus disrupted irregular MV corresponded to the histological finding of NEC component in all five cases. These endoscopic features were all significantly more frequent in G-NECs than G-NETs (n = 22) or common-type gastric adenocarcinomas (n = 45).

CONCLUSIONS

These endoscopic features should be taken into consideration to increase the index of suspicion and to improve the accuracy of target biopsies for G-NEC.

Feasibility of underwater endoscopic mucosal resection for endoscopic management of gastric neoplasms in patients with familial adenomatous polyposis

BACKGROUND

Underwater endoscopic mucosal resection (UEMR) has been developed as an effective endoscopic intervention for colon, rectum, and duodenum neoplasms. However, there are no comprehensive reports regarding the stomach, and its safety and efficacy are unknown. We aimed to examine the feasibility of UEMR for gastric neoplasms in patients with familial adenomatous polyposis (FAP).

METHODS

We retrospectively extracted data of patients with FAP who underwent endoscopic resection (ER) for gastric neoplasms at Osaka International Cancer Institute from February 2009 to December 2018. Elevated gastric neoplasms of ≤ 20 mm in diameter were extracted, and conventional endoscopic mucosal resection (CEMR) and UEMR were compared. Furthermore, outcomes after ER until March 2020 were examined.

RESULTS

91 endoscopically resected gastric neoplasms were extracted from 31 patients with 26 pedigrees, and 12 neoplasms underwent CEMR and 25 neoplasms underwent UEMR was compared. The procedure time was shorter for UEMR than for CEMR. There was no significant difference between en bloc resection and R0 resection rates by EMR methods. CEMR and UEMR showed postoperative hemorrhage rates of 8% and 0%, respectively. Residual/local recurrent neoplasms were identified in four lesions (4%), but additional endoscopic intervention (three UEMR and one cauterization) resulted in a local cure.

CONCLUSION

UEMR was feasible in gastric neoplasms of FAP patients, especially in elevated lesions and those of ≤ 20 mm in diameter.

Predictors of stricture after non-circumferential endoscopic submucosal dissection of the esophagus and single-dose triamcinolone injection immediately after the procedure

BACKGROUND AND AIMS

Local triamcinolone (TA) injection is widely used to prevent stricture formation after endoscopic submucosal dissection (ESD). However, stricture develops in up to 45% of patients despite this prophylactic measure. We therefore conducted a single-center prospective study to identify predictors of stricture after esophageal ESD and local TA injection.

METHODS

Patients who underwent esophageal ESD and local TA injection and who were comprehensively assessed for lesion- and ESD-related factors were included in the study. Multivariate analyses were conducted to identify the predictors of stricture.

RESULTS

A total of 203 patients were included in the analysis. Multivariate analysis identified residual mucosal width ≤5 mm (odds ratio [OR], 29.0; P < .0001) or 6 to 10 mm (OR, 3.7; P = .04), history of chemoradiotherapy (OR, 5.1; P = .045), and tumor in the cervical or upper thoracic esophagus (OR, 3.8; P = .018) as independent predictors of stricture. Based on the ORs of the predictors, patients were stratified into 2 groups according to stricture risk: patients in the high-risk group (residual mucosal width ≤5 mm or 6-10 mm with another predictor) had a stricture rate of 52.5% (31 of 59 cases), and patients in the low-risk group (residual mucosal width ≥11 mm or 6-10 mm without other predictors) had a stricture rate of 6.3% (9 of 144 cases).

CONCLUSIONS

We identified predictors of stricture after ESD and local TA injection. Local TA injection prevented stricture formation after ESD in low-risk patients but was not sufficient to prevent stricture in high-risk patients. Additional interventions should thus be considered in high-risk patients. (University Hospital Medical Network Clinical Trials Registry number: UMIN 000028894.).

Potential role of a novel endoscopic retrieval bag for large colorectal resected specimen: a proof-of-concept study

Endoscopic submucosal dissection enables en bloc resection of large superficial colorectal neoplasms. However, it is sometimes challenging to retrieve a large resected specimen via the anus without sample fragmentation. A novel "bag-type" retrieval device has been developed to accomplish complete isolation and non-destructive delivery of oversized specimens. This single-center retrospective study was performed to demonstrate the efficacy of this device for large colorectal resected specimens. Among 17 patients, we identified 18 superficial colorectal lesions for which the use of a novel retrieval device (Endo Carry Large Type) was indicated at specimen delivery at a referral cancer institute from March 2021 to July 2022. The median (interquartile range) tumor size was 62.5 (52.0-79.5) mm. Retrieval of 17 (94%) of 18 resected specimens was performed using the Endo Carry Large Type, and 16 (89%) were successfully retrieved without sample fragmentation. The median (interquartile range) retrieval time was 4 (4-8) minutes, and no apparent adverse events were observed. The novel Endo Carry Large Type device can accomplish colorectal specimen retrieval safely and quickly without specimen damage and therefore may contribute to accurate pathological diagnosis.

Endoscopic resection for local residual or recurrent cancer after definitive chemoradiotherapy or radiotherapy for esophageal squamous cell carcinoma

Chemoradiotherapy (CRT) and radiotherapy (RT) are treatment options for esophageal squamous cell carcinoma (ESCC), but local residual/recurrent cancer after CRT/RT is a major problem. Endoscopic resection (ER) is an effective treatment option for local residual/recurrent cancer. To ensure the efficacy of ER, complete removal of endoscopically visible lesions with cancer-free vertical margins is desired. This study aimed to identify the endoscopic parameters associated with the complete endoscopic removal of local residual/recurrent cancer. In this single-center, retrospective study, we used a prospectively maintained database to identify esophageal lesions that were diagnosed as local residual/recurrent cancer after CRT/RT and treated by ER between January 2012 and December 2019. We evaluated the associations of endoscopic R0 resection with findings on conventional endoscopy and endoscopic ultrasonography (EUS). In total, 98 lesions (83 cases) were identified from our database. The rate of endoscopic R0 resection was higher for flat lesions (100% versus 77%, P = 0.00014). EUS was performed for 24 non-flat lesions, and endoscopic R0 resection was achieved for 94% of lesions with an uninterrupted fifth layer. Flat lesions on conventional endoscopy and lesions with an uninterrupted fifth layer on EUS are good candidates for ER.

A single-center prospective study evaluating the usefulness of artificial intelligence for the diagnosis of esophageal squamous cell carcinoma in a real-time setting

BACKGROUND

Several pre-clinical studies have reported the usefulness of artificial intelligence (AI) systems in the diagnosis of esophageal squamous cell carcinoma (ESCC). We conducted this study to evaluate the usefulness of an AI system for real-time diagnosis of ESCC in a clinical setting.

METHODS

This study followed a single-center prospective single-arm non-inferiority design. Patients at high risk for ESCC were recruited and real-time diagnosis by the AI system was compared with that of endoscopists for lesions suspected to be ESCC. The primary outcomes were the diagnostic accuracy of the AI system and endoscopists. The secondary outcomes were sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and adverse events.

RESULTS

A total of 237 lesions were evaluated. The accuracy, sensitivity, and specificity of the AI system were 80.6%, 68.2%, and 83.4%, respectively. The accuracy, sensitivity, and specificity of endoscopists were 85.7%, 61.4%, and 91.2%, respectively. The difference between the accuracy of the AI system and that of the endoscopists was - 5.1%, and the lower limit of the 90% confidence interval was less than the non-inferiority margin.

CONCLUSIONS

The non-inferiority of the AI system in comparison with endoscopists in the real-time diagnosis of ESCC in a clinical setting was not proven.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (jRCTs052200015, 18/05/2020).

Efficacy and safety of intensive downstaging polypectomy (IDP) for multiple duodenal adenomas in patients with familial adenomatous polyposis: a prospective cohort study

BACKGROUND

 Patients with familial adenomatous polyposis (FAP) risk developing multiple duodenal adenomas (MDAs), leading to duodenal cancer and death. We investigated the efficacy and safety of intensive downstaging polypectomy (IDP) for MDAs integrated with new-generation procedures.

METHODS

 This prospective phase II study, conducted at a tertiary cancer center, enrolled patients with FAP who had MDAs. We performed IDP including cold snare/forceps polypectomy (CSP/CFP) and underwater endoscopic mucosal resection (UEMR). The primary end point was the downstaging of Spigelman stage at 1-year follow-up.

RESULTS

 2424 duodenal polyps in 58 patients with FAP underwent IDP, including 2413 CSPs in 57 patients, seven CFPs in one patient, and four UEMRs in four patients. Only one major adverse event was observed (grade 3 hyperamylasemia) without clinical manifestations. We performed additional UEMR, CSP, and CFP for one, 12, and 22 patients, respectively, during initial follow-up. Overall, 55 patients completed protocol examination; the Spigelman stage was significantly reduced at the 1-year follow-up endoscopy (P < 0.001), with downstaging observed in 39 patients (71 %). Among the 26 patients with Spigelman stage IV at initial examination and protocol completion, 23 (88 %) showed downstaging. There was no major change in Spigelman stages from 1-year follow-up esophagogastroduodenoscopy to a median of 37 months (range 3-56).

CONCLUSIONS

 IDP, including new-generation procedures, showed significant downstaging with acceptable adverse events for MDA in patients with FAP, even those with advanced-stage disease. Lesion selection for different resection techniques may be important for suitable and sustainable management of MDA in patients with FAP.

Boring biopsy with rapid on-site evaluation for gastric gastrointestinal stromal tumor: A pilot study

One of 4 patients (25%) and 2 of 3 patients (67%) were correctly diagnosed by conventional and hot boring biopsies, respectively. The median procedure time of conventional and hot boring biopsies was 21 (range, 13-33) and 17 (range, 16-23) min, respectively. Rapid on-site evaluation was performed totally 12 times in 7 patients. The positive and negative predictive values of rapid on-site evaluation for gastrointestinal stromal tumor were 0.5 (0.12-0.88) and 1.0 (0.42-1.00), respectively.

Impact of endoscopic surveillance on mortality of metachronous esophageal and head and neck cancer after esophageal endoscopic resection

BACKGROUND AND AIM

As more superficial esophageal cancer (EC) patients are being treated with endoscopic resection (ER), it is important to understand the outcomes, including survival data, of patients who develop metachronous EC and head and neck cancer (HNC). We aimed to evaluate the long-term surveillance and survival outcomes of metachronous EC and HNC after esophageal ER.

METHODS

This study included 627 patients who underwent ER of superficial esophageal squamous cell carcinoma from 2008 to 2016 and were generally followed by annual or biannual esophagogastroduodenoscopy up to 2019 at Osaka International Cancer Institute. Data on metachronous cancer development and causes of death were collected from an integrated database of hospital-based cancer registry and Vital Statistics of Japan.

RESULTS

During a median (range) follow-up period of 67.4 (3.8-142.7) months, 230 patients (36.7%) developed 500 metachronous ECs and 126 patients (20.1%) developed 239 metachronous HNCs, post-ER of index EC. The 3-year, 5-year, and 7-year cumulative incidences were 25.8%, 36.0%, and 43.6% for metachronous EC and 10.9%, 16.0%, and 26.9% for metachronous HNC, respectively. No patients died of metachronous EC, and only seven patients (1.1%) died of metachronous HNC. The 3-year, 5-year, and 7-year disease-specific survival rates were 99.8%, 99.6%, and 98.6%, respectively.

CONCLUSIONS

The incidences of metachronous EC and HNC increase with time over 5 years after esophageal ER; therefore, surveillance endoscopy should be continued over 5 years. Endoscopic surveillance is useful for survivors after esophageal ER given the high incidence and extremely low mortality of metachronous EC and HNC.

Indication of emergency colonoscopy after colorectal endoscopic submucosal dissection: A proposal of hematochezia scale

BACKGROUND AND AIM

Hematochezia is a major adverse event associated with colorectal endoscopic submucosal dissection (ESD). This study aimed to distinguish between hematochezia that required endoscopic hemostasis and hematochezia that required no hemostasis.

METHODS

This retrospective study included consecutive patients who underwent ESD for colorectal tumors at the Osaka International Cancer Institute between September 2017 and August 2020. The exclusion criteria were as follows: patients with coexisting advanced colorectal cancers or inflammatory bowel diseases, patients who received incomplete ESD or emergency surgery, or patients who underwent ESD for multiple lesions. We evaluated whether the patients had hematochezia and underwent emergency colonoscopy and hemostasis during hospitalization. The degree of hematochezia in the saved photographs was assessed using the hematochezia scale and classified as mild, moderate, or severe. Blood pressure, heart rate, time from ESD to first hematochezia, and total number of hematochezia episodes were also evaluated.

RESULTS

Among the 437 patients who underwent ESD, 44 were excluded, and 393 patients were evaluated. Hematochezia was observed in 100 patients (25%). Emergency colonoscopy was performed in 12 patients (3%), and hemostasis was required in six patients (2%). For patients with hematochezia, only mild hematochezia and hematochezia that developed ≤ 48 h after ESD were significantly associated with no intervention for hemostasis. The positive predictive value for no intervention for hemostasis was 100% (93-100%) for mild hematochezia and 98% (93-100%) for hematochezia ≤ 48 h.

CONCLUSIONS

Mild hematochezia and hematochezia ≤ 48 h were negative predictors of hemostasis, in which emergency colonoscopy may be avoided.

Clinical features of superficial esophagus squamous cell carcinoma according to alcohol-degrading enzyme ADH1B and ALDH2 genotypes

BACKGROUND

Inactivated alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are related to esophageal carcinogenesis. We aimed to clarify the clinical features associated with the alcohol-degrading enzyme genotypes, ADH1B and ALDH2. We also investigated the risk factors for metachronous esophageal squamous cell carcinoma (ESCC) and head and neck SCC (HNSCC).

METHODS

We conducted a single-center, retrospective study including patients with ESCC treated by endoscopic resection. Patients were recruited between October 2020 and September 2021. Buccal mucosal swabs were obtained from them to analyze the genetic polymorphisms affecting ADH (ADH1B) and ALDH (ALDH2) activity. Patients were categorized into three groups: both inactivated = double-inactivated group; inactivated ADH1B or ALDH2 = single-inactivated group; and both activated = activated group.

RESULTS

Among the 297 enrolled patients, patients in the double-inactivated group were significantly younger (P < 0.001) and 60% of them were ≤ 50 years old. This group also had more ESCCs located in the upper esophagus (P < 0.001) and more simultaneous multiple ESCCs (P = 0.044). More than half of the patients had multiple Lugol-voiding lesions (LVLs) (P < 0.001) and heavy alcohol consumers (P = 0.012). Metachronous ESCC and HNSCC were more common in the double-inactivated group (P < 0.001, P = 0.001). Multivariate analysis identified located in the upper esophagus, multiple LVLs and history of HNSCC as risk factors for metachronous ESCC.

CONCLUSIONS

Activation patterns of alcohol-metabolizing enzymes were related to age at ESCC onset, lesion location, and metachronous ESCC and HNSCC. Different approaches to the prophylaxis and treatment of esophageal cancer should be considered, depending on the enzyme activity pattern.

Long-term outcomes after endoscopic resection for late-elderly patients with early gastric cancer

BACKGROUND AND AIMS

With the population aging, the incidence of early gastric cancer (EGC) is increasing. We aimed to clarify the indications for endoscopic resection (ER) in late-elderly patients with EGC in terms of life expectancy.

METHODS

Patients aged ≥75 years who underwent ER for EGC at our institution from January 2007 to December 2012 were enrolled. Clinical data, including Eastern Cooperative Oncology Group performance status (ECOG-PS), Charlson comorbidity index, and Prognostic Nutritional Index (PNI), were collected at the time of ER. Overall survival (OS) was the main outcome measure.

RESULTS

Four hundred consecutive patients were enrolled. Mean patient age was 79.3 years (range, 75-93). The 5-year follow-up rate was 89.0% (median follow-up period, 5.6 years). Five-year OS was 80.8% (95% confidence interval [CI], 76.4-84.4), and 5-year net survival standardized for age, sex, and calendar year was 1.09 (95% CI, 1.03-1.15). With a multivariate analysis, ECOG-PS 2 to 4 (hazard ratio, 8.84; 95% CI, 3.07-25.4), PNI <49.1 (hazard ratio, 2.49; 95% CI, 1.53-4.06), and eCura C-2 (hazard ratio, 1.79; 95% CI, 1.11-2.88) were independent prognostic factors. When none of these factors was met, the 5-year OS rate was 90.4% (95% CI, 84.0-94.3).

CONCLUSIONS

ER for EGC in late-elderly patients may improve life expectancy. ER is recommended in patients with a good ECOG-PS and PNI and in whom ER is expected to be non-eCura C-2.

Positive predictive value of the clinical diagnosis of T1a-epithelial/lamina propria esophageal cancer depends on lesion size

OBJECTIVES

Endoscopic resection (ER) is a minimally invasive treatment for esophageal squamous cell carcinoma (ESCC). However, stricture may develop after ER for widespread lesions. Application of ER is justified if these cancers are pathological T1a-epithelial/lamina propria (pEP/LPM) cancers that can be cured by ER. We conducted a study to clarify the association between pathological invasion depth and lesion size or circumference in clinical (c) EP/LPM cancers.

METHODS

From our database, we identified patients diagnosed with cEP/LPM ESCC via endoscopic examination who underwent endoscopic or surgical tumor resection. The accuracy of the cEP/LPM ESCC diagnosis was determined by histologically diagnosing cancer invasion depth as a reference standard.

RESULTS

Between January 2015 and December 2019, 1271 cancer patients were diagnosed with cEP/LPM ESCC, of which 1195 (94.0%) were correctly diagnosed with pEP/LPM cancer. The positive predictive value (PPV) classified according to lesion sizes of ≤25, 26-49, and ≥50 mm was 95.8% (981/1024 lesions), 89.7% (191/213 lesions), and 67.6% (23/34 lesions), respectively. PPV according to the circumferential extent of <3/4, ≥3/4, and <1, and whole was 94.6% (1164/1230 lesions), 75.0% (24/32 lesions), and 77.8% (7/9 lesions), respectively. In multivariate analysis, the PPV of cEP/LPM ESCC was significantly associated with lesion size (P < 0.001) and male sex.

CONCLUSIONS

Between January 2015 and December 2019, 1271 cancer patients were diagnosed with cEP/LPM ESCC, of which 1195 (94.0%) were correctly diagnosed with pEP/LPM cancer. The PPV of cEP/LPM ESCC was related to lesion size. Treatment should be determined considering the high risk of cancer invasion into the muscularis mucosa or deeper in cEP/LPM cancers with a lesion size of ≥50 mm.

Favorable long-term outcomes of endoscopic resection for nonampullary duodenal neuroendocrine tumor

BACKGROUND AND AIM

The long-term outcomes of endoscopic resection for nonampullary duodenal neuroendocrine tumors are limited. We aimed to clarify it.

METHODS

Consecutive patients with nonampullary duodenal neuroendocrine tumors endoscopically treated at our institute between January 2005 and June 2020 were included in this retrospective study. En bloc and R0 resection rates and adverse events were evaluated as short-term outcomes of endoscopic resection. The 5-year overall and recurrence-free survival rates of patients after endoscopic resection were calculated as long-term outcomes.

RESULTS

Of 34 patients with 34 lesions, 33 patients (97%) underwent endoscopic mucosal resection, and one (3%) underwent endoscopic submucosal dissection. En bloc resection was achieved in 33 lesions (97%). R0 resection was achieved in 20 lesions (59%). The median tumor size was 6 mm (range: 3-13). Thirty-one lesions (91%) and three lesions (9%) were classified as G1 and G2, respectively. Lymphovascular invasion was observed in six lesions (18%). Intraprocedural perforation occurred in four patients (12%) who were conservatively treated with endoscopic closure. All 34 patients were followed up without additional treatment after endoscopic resection, and no recurrence or metastasis developed during the median follow-up period of 47.9 months (range: 9.0-187.1). The 5-year overall survival and recurrence-free survival rates were 87.1% and 100%, respectively.

CONCLUSIONS

Endoscopic resection provided a favorable long-term prognosis for patients with nonampullary duodenal neuroendocrine tumors without lymph node metastasis.

Delineating the extent of esophageal squamous cell carcinoma

BACKGROUND

Lugol chromoendoscopy has been conventionally used for the detection and delineation of esophageal squamous cell carcinoma (SCC). However, the boundaries of some lesions are unclear even with Lugol chromoendoscopy, and there is a risk of residual lesions or over-excision. This study aimed to evaluate the utility of narrow-band imaging (NBI) for the delineation of esophageal SCC in endoscopic resection.

METHODS

Among 367 esophageal SCCs endoscopically resected between January and December 2019 at our institute, this retrospective study included consecutive lesions, which were first marked with NBI, followed by Lugol chromoendoscopy. The proportion of residual cancer, which was defined as histologically proven cancer confirmed adjacent to the scar within 1 year after endoscopic resection, was evaluated. To evaluate whether the marks added by Lugol chromoendoscopy after NBI marking were more reliable, we evaluated the presence of cancer in the iodine-unstained area outside the NBI-determined marks, i.e., the cancerous area missed by NBI. The presence of cancer in the iodine-stained areas inside the NBI-determined marks, i.e., the cancerous area missed by Lugol, was also evaluated. These were compared to assess the risk of residual cancer in endoscopic resection with NBI and Lugol chromoendoscopy.

RESULTS

Among 304 lesions, 2 (0.7%) residual cancers were detected. The cancerous area missed by NBI and the cancerous area missed by Lugol were identified in 18 (6%) and 43 (14%) lesions, respectively (P = 0.001).

CONCLUSIONS

NBI might be acceptable for delineating the extent of esophageal SCCs that are difficult to delineate with Lugol chromoendoscopy.

Curative value of underwater endoscopic mucosal resection for submucosally invasive colorectal cancer

BACKGROUND AND AIM

Occasionally, colorectal tumors without characteristics of deep submucosal invasion are found to be invasive upon pathological evaluation after endoscopic resection (ER). Because the resection depth for underwater endoscopic mucosal resection (UEMR) has not been clarified, we evaluated the feasibility of UEMR for pathologically invasive colorectal cancer (pT1-CRC).

METHODS

We retrospectively investigated data on the backgrounds and outcomes of patients with pT1-CRC who underwent UEMR between January 2014 and June 2019 at our institute. As a reference standard, the backgrounds and outcomes of pT1-CRCs that had undergone conventional EMR (CEMR) were also investigated.

RESULTS

Thirty-one patients (median age, 68 years [range, 32-88 years]; 22 men [71%]) were treated with UEMR. Median lesion size was 17 mm (range, 6-50 mm). The endoscopic complete resection rate was 100%. The overall en bloc resection rate was 77%, and the VM0, HM0, and R0 resection rates were 81%, 58%, and 55%, respectively. In cases of pT1a (invasion <1000 μm)-CRC (n = 14), the en bloc, VM0, and R0 resection rates were 92%, 100%, and 71%, respectively. Seventeen patients (five with risk factors for lymph node metastasis and 12 without) were followed up, and no local recurrence and distant metastasis were observed during the follow-up period (median follow-up period, 18 months [range, 6-62 months]) after UEMR. The outcomes of UEMR seemed to be comparable with those of CEMR (n = 32).

CONCLUSIONS

The VM0 rate of UEMR for pT1-CRC, especially for pT1a-CRC, without characteristics of deep submucosal invasion seems feasible.

Underwater endoscopic mucosal resection versus endoscopic submucosal dissection for 20-30 mm colorectal polyps

BACKGROUND AND AIM

Endoscopic submucosal dissection (ESD) for large polyps provides a high en bloc resection rate, accurate pathological diagnosis, and low recurrence rate. However, ESD requires advanced techniques, and underwater endoscopic mucosal resection (UEMR) is an alternative. We investigated the efficacy and safety of UEMR for 20-30 mm colorectal lesions compared with ESD.

METHODS

We retrospectively evaluated systematically collected data of patients who underwent UEMR or ESD for 20-30 mm sessile colorectal lesions. Outcome measures were the incidence of local recurrence, procedure time, en bloc resection rate, and incidence of adverse events. We performed propensity score matching and inverse probability weighting adjustment to control for possible confounders.

RESULTS

We evaluated 125 patients undergoing UEMR and 306 patients undergoing ESD. Using propensity score matching, we analyzed 74 lesions in each group. UEMR had a shorter procedure time than ESD [6.7 min (95% confidence interval (CI), 5.3-8.1 min) vs 64.8 min (95% CI, 57.4-72.2 min), respectively]. Although the en bloc resection rate with UEMR was inferior to ESD [61% (95% CI, 49-72%) vs 99% (95% CI, 93-100%), respectively], there was no significant difference in the local recurrence rate between the procedures [0% (95% CI, 0-4.0%) in each group]. Inverse probability weighting adjustment revealed that neither ESD nor UEMR had a significant association with local recurrence.

CONCLUSIONS

Underwater endoscopic mucosal resection for 20-30  mm colorectal lesions was comparable with ESD regarding long-term outcomes, with a shorter procedure time, despite the lower en bloc resection rate.

Propensity score-matched analysis of endoscopic resection for recurrent colorectal neoplasms: A pilot study

BACKGROUND AND AIM

Local residual/recurrent colorectal lesions after endoscopic resection (ER) are difficult to treat with conventional ER. Underwater endoscopic mucosal resection (UEMR) and endoscopic submucosal dissection (ESD) are reportedly effective. We investigated the appropriate indications of ESD and UEMR for recurrent colorectal lesions.

METHODS

This single-center, retrospective, observational study was conducted at a tertiary cancer institute. Patients who underwent UEMR or ESD for residual/recurrent colorectal lesions after ER from October 2013 to February 2019 were enrolled. Propensity score matching was performed between the UEMR and ESD groups to compare the clinical characteristics, treatment, and outcomes.

RESULTS

In total, 30 UEMRs and 21 ESDs were performed. Median (range) diameter of the lesions was 8 mm (2-22 mm) in UEMR and 15 mm (2-58 mm) in ESD. Median procedure time in UEMR was significantly shorter than that of ESD (4 min [2-15 min] vs 70 min [17-193 min], P < 0.001). En bloc and complete resection rates of ESD were significantly higher than that of UEMR (73% vs 100%, 41% vs 81%, respectively). No adverse events occurred with UEMR, but there were two cases (10%) of delayed perforation with ESD. Neither group reported recurrence after treatment. Propensity score-matched cases showed significantly shorter procedure time and hospitalization period in UEMR than in ESD.

CONCLUSIONS

The outcomes of UEMR and ESD were comparable. UEMR could be a useful salvage therapy for small local residual/recurrent colorectal lesions after ER with shorter procedure time and hospitalization period.

Pre-ampullary location and size ≥10 mm are independent predictors for high-grade superficial non-ampullary duodenal epithelial tumors

BACKGROUND AND AIM

The incidence of identified superficial non-ampullary duodenal epithelial tumors (SNADETs) has been increasing with recent advances in endoscopic diagnosis. Nevertheless, the clinical features of SNADETs with malignant potential remain unclear. The aim of the present study was to clarify the clinical characteristics of high-grade SNADETs.

METHODS

A total of 328 SNADETs that had been endoscopically or surgically resected between January 2013 and April 2019 were identified from an endoscopic and pathological database. Clinical characteristics were compared between mucosal low-grade neoplasm (n = 154) and mucosal high-grade neoplasm/submucosal carcinoma (HGN/SMC, n = 174).

RESULTS

In univariate analysis, tumor size, pre-ampullary tumor location, red color, and rough/nodular surface were significantly associated with HGN/SMC. In multivariate analysis (odds ratio [95% confidence interval]), large (≥10 mm) tumor size (odds ratio: 4.5, 95% confidence interval: 2.6-7.7, P < 0.001) and pre-ampullary tumor location (odds ratio: 2.1, 95% confidence interval: 1.3-3.5, P = 0.004) were independent predictors for HGN/SMC. Analysis of histological phenotypes revealed that the proportion of tumors that were HGN/SMC was much greater for gastric-type tumors (21/23 lesions, 91%) than for intestinal-type tumors (150/302 lesions, 50%) (P < 0.001) and that all gastric-type tumors were located in the pre-ampullary portion.

CONCLUSIONS

Pre-ampullary location and large tumor size are independent predictors for HGN/SMC SNADETs. Pre-ampullary tumor location is significantly associated with gastric histological phenotype. These findings may help in decision making for endoscopic treatment, active indication for pre-ampullary tumor or tumor ≥10 mm, and understanding the pathophysiology of SNADETs.

Endoscopic findings in the soft palatal mucosa are associated with the risk of esophageal squamous cell carcinoma

BACKGROUND AND AIM

We investigated endoscopic findings of the soft palatal mucosa to identify factors associated with esophageal squamous cell carcinoma (ESCC).

METHODS

This study was conducted during endoscopic examinations of subjects at Osaka International Cancer Institute from January 2020 through May 2020. We took endoscopic images of the soft palate under non-magnifying and mild-magnifying observations. Subjects with ESCC or a history of ESCC were defined as the ESCC group. Two endoscopists who were blinded to subjects' clinical information interpreted 10 endoscopic findings: melanosis, brownish changes, whitish epithelium, vasodilation, circular alignment of dilated vessels, uneven surface, uneven epithelial color, uneven vessel visibility, palate ridge, and erosion. Subjects were interviewed about their alcohol use, smoking, and flushing reactions.

RESULTS

Two hundred eighty-two subjects, including 151 in the ESCC group and 131 in the non-ESCC group, were included in the analysis. Univariate analyses and multivariate logistic regression demonstrated that melanosis, whitish epithelium, and vasodilation were significantly associated with ESCC. The positive likelihood ratios (PLRs) of melanosis, whitish epithelium, and vasodilation were 3.3, 4.2, and 2.8, respectively. Additionally, the PLRs for three of the endoscopic findings in subjects with drinking and smoking habits were higher than in those without these habits-PLRs ranging from 7.23 to 19.1. High PLRs for three endoscopic findings suggested a high possibility of ESCC. Interobserver agreement was substantial for whitish epithelium, moderate for melanosis, and fair for vasodilation.

CONCLUSIONS

Three endoscopic findings in soft palate were considered to be useful as alarming signs that indicate ESCC risk.

Magnifying endoscopy with crystal violet staining for immune checkpoint inhibitor-associated colitis

BACKGROUND AND AIM

There exists no evidence on the relationship between endoscopic and histologic findings. Furthermore, even after multiple biopsy specimens were obtained, histologic examination usually fails to show the characteristic features of immune checkpoint inhibitor-associated colitis. In this study, we explored the endoscopic and histologic findings of immune checkpoint inhibitor-associated colitis.

METHODS

Patients diagnosed with immune checkpoint inhibitor-associated colitis at our hospital between March 2018 and December 2018 were retrospectively assessed. The degree of mucosal inflammation was evaluated using endoscopic inflammation grade (inactive, mild, moderate, or severe disease) and further observed using magnifying endoscopy with crystal violet staining. Pit structures were classified into three types: regularly arranged pits with circular or elliptical shape (R type), irregularly arranged pits with inhomogeneous size and morphology (IR type), and pits with reduced density or pits that partially disappeared (AD type).

RESULTS

Eleven patients (median age, 71 years; range, 44-83 years) were diagnosed with immune checkpoint inhibitor-associated colitis. All characteristic histologic findings, including crypt distortion, crypt abscesses, and apoptotic bodies, were observed at sites with moderate-to-severe endoscopic inflammation but not at sites with inactive-to-mild endoscopic inflammation. Characteristic histologic features were observed in 0%, 50%, and 100% of R-type, IR-type, and AD-type mucosa, respectively.

CONCLUSIONS

We revealed the possible utility of endoscopic images for selecting suitable target sites for biopsy and showed that endoscopic findings could reduce the time lag associated with tissue diagnosis and sampling errors due to biopsy.

Ultra-magnifying narrow-band imaging for endoscopic diagnosis of gastric intestinal metaplasia: a pilot image analysis study

Background and study aims  Narrow-band imaging (NBI) with or without magnification has recently been used for diagnosis of gastric intestinal metaplasia (GIM). Endocytoscopy is a newly developed endoscopic technique that enables ultra-high (500 ×) magnification of the digestive tract mucosa. This study aimed to analyze the ultra-magnifying NBI characteristics of GIM. Patients and methods  This was a retrospective observational study conducted in a cancer referral center. Patients who underwent ultra-magnifying NBI of the gastric mucosa using endocytoscopy were eligible. A soft black cap was used for non-contact observation. We compared the characteristic findings of GIM by ultra-magnifying NBI of metaplastic and non-metaplastic mucosae. A reference standard for GIM in this study was conventional magnifying NBI findings of GIM. Results  We obtained 28 images of metaplastic mucosa and 32 of non-metaplastic mucosa from 38 patients. Ultra-magnifying NBI revealed the cobblestone-like cellular structure in the marginal crypt epithelium of metaplastic and non-metaplastic mucosa. Diagnostic values (sensitivity, specificity, accuracy and kappa value [95 % confidence interval]) for the heterogeneous cellular structure and rough contour of the marginal crypt epithelium were 82 % (68 %-96 %), 94 % (85 %-100 %), 88 % (80 %-96 %), and 0.70, and 86 % (73 %-99 %), 94 % (85 %-100 %), 90 % (82 %-98 %), and 0.71, respectively. Conclusions  The characteristic ultrastructural features of GIM were identified by ultra-magnifying NBI, warranting validation of diagnostic value in a prospective study.

Endoscopic Features of Superficial Esophageal Squamous Cell Carcinoma in Patients with Very Low Risk Factors (Female, Nondrinking, and Nonsmoking): A Case-Control Study

BACKGROUND

Although esophageal squamous cell carcinoma (ESCC) is more likely to develop in patients with any risk factor (male, drinking, or smoking), it is sometimes detected in patients with very low risk factors (female, nondrinking, and nonsmoking). We examined the endoscopic features of superficial ESCC in patients with very low risk factors.

METHODS

In this single-center case-control study, 666 patients with 666 superficial ESCC lesions were divided into 2 groups: those with very low risk factors (very low-risk group, n = 34) and those with any risk factors (any-risk group, n = 632). After case-control selection at a 1:5 ratio, the very low-risk group comprised 34 patients and the any-risk group comprised 170 patients. We compared the baseline characteristics, endoscopic findings, and treatment results (including pathological diagnosis) between the 2 groups.

RESULTS

There were no statistically significant differences between the 2 groups in age, tumor size, tumor location, tumor morphology, or treatment results (including tumor depth and lymphovascular invasion). A longitudinal lesion with an attachment of white keratinized epithelium was more likely to be detected in the very low-risk group than the any-risk group (61.8 vs. 17.6%, respectively; p < 0.001).

CONCLUSIONS

ESCC in patients with very low risk factors is rare but can be encountered in daily practice. A longitudinal lesion with an attachment of white keratinized epithelium is its main characteristic, which is slightly different from that of patients with any risk factors.

Long-term outcomes after endoscopic submucosal dissection for differentiated-type early gastric cancer that fulfilled expanded indication criteria: A prospective cohort study

BACKGROUND AND AIM

Endoscopic resection for early gastric cancer (EGC) is widely performed. However, there is still a paucity of strong evidence regarding long-term outcomes after endoscopic submucosal dissection (ESD) for the expanded indication criteria of the Japanese guidelines (ver. 2010).

METHODS

Endoscopic submucosal dissection was performed in patients with EGC that met the expanded indication criteria: (i) cT1a, differentiated-type EGC of 2 to 5 cm, ulcer negative or (ii) cT1a, differentiated-type EGC of ≤3 cm, ulcer positive. Patients whose pathological examination fulfilled the curative resection criteria were then enrolled in this cohort study: negative vertical margin, negative lymphovascular invasion, and (i) pT1a, differentiated-type, and ulcer negative; (ii) pT1a, differentiated-type, ≤3 cm, and ulcer positive; or (iii) pT1b1 (<500-μm submucosal invasion), differentiated-type, and ≤3 cm. Patients with only a positive horizontal margin as a noncurative factor were included for follow-up.

RESULTS

From September 2003 to February 2012, a total of 356 patients underwent ESD, and 214 were enrolled in the survival analysis. One hundred twenty patients (56%) had >2 cm in diameter and ulcer-negative lesions, and 94 (44%) had ≤3 cm and ulcer-positive lesions. The vital status at 5 years after ESD was confirmed in all (100%) patients. No local or metastatic recurrence was detected; however, 26 metachronous gastric cancers developed, and 1 patient died of metachronous gastric cancer. The 5-year disease-specific and overall survival rates were 99.5% (95% confidence interval [CI], 97.2%-100%) and 93.9% (95% CI, 89.8%-96.4%), respectively.

CONCLUSION

ESD for EGC that fulfills the expanded criteria is feasible and shows favorable long-term outcomes.

Esophageal metal stent for malignant obstruction after prior radiotherapy

The association between severe adverse events (SAEs) and prior radiotherapy or stent type remains controversial. Patients with esophageal or esophagogastric junctional cancer who underwent stent placement (2005–2019) were enrolled in this retrospective study conducted at a tertiary cancer institute in Japan. The exclusion criteria were follow-up period of < 1 month and insufficient data on stent type or cancer characteristics. We used Mann–Whitney’s U test for quantitative data and Fisher’s exact test for categorical data. Multivariate analysis was performed using a logistic regression model. 107 stents were placed. Low radial-force stents (L group) were used in 51 procedures and high radial-force stents (H group) in 56 procedures. SAEs developed after nine procedures, the median interval from stent placement being 6 days (range, 1–141 days). SAEs occurred more frequently in the H (14%: 8/56) than in the L group (2%: 1/51) (P = 0.03). In patients who had undergone prior radiotherapy, SAEs were more frequent in the H (36%: 4/11) than in the L group (0%: 0/13) (P = 0.03). Re-obstruction and migration occurred after 16 and three procedures, respectively; these rates did not differ significantly between groups (P = 0.59, P = 1, respectively). Low radial-force stents may reduce the risk of SAEs after esophageal stenting.

Differences in image-enhanced endoscopic findings between Helicobacter pylori -associated and autoimmune gastritis

Background and study aims  The aim of this study was to elucidate the differences in image-enhanced endoscopy (IEE) findings between Helicobacter - pylori -associated and autoimmune gastritis. Patients and methods  Seven H. pylori -naïve, 21 patients with H. pylori -associated gastritis and seven with autoimmune gastritis were enrolled. Mucosal atrophy in the corpus was evaluated using autofluorescence imaging and classified into small, medium and large. In a 2 × 2-cm area of the lesser curvature of the lower corpus, micromucosal pattern was evaluated by magnifying narrow band imaging and proportion of foveola (FV)- and groove (GR)-type mucosa was classified into FV > 80 %, FV 50 % to 80 %, GR 50 % to 80 %, and GR > 80 %, then a biopsy specimen was taken. Results  Fifteen of 21 (71 %) H. pylori -associated gastritis patients exhibited medium-to-large atrophic mucosa at the corpus lesser curvature. All autoimmune gastritis patients had large atrophic mucosa throughout the corpus ( P  < 0.001). All H. pylori -naïve patients had the FV > 80 % micromucosal pattern. Nineteen of 21 (90 %) H. pylori -associated gastritis patients had varying proportions of GR- and FV-type mucosae and five of seven (71 %) autoimmune gastritis patients showed FV > 80 % mucosa ( P  < 0.001). Compared with patients who were H. pylori -naïve, patients with H. pylori -associated and autoimmune gastritis exhibited a higher grade of atrophy ( P  < 0.001), but only patients with H. pylori -associated gastritis showed a higher grade of intestinal metaplasia ( P  = 0.022). Large mucosal atrophy with FV > 80 % micromucosal pattern had sensitivity of 71 % (95 % CI: 29 %-96 %) and specificity of 100 % (95 % CI: 88 % to 100 %) for diagnosis of autoimmune gastritis. Conclusions  IEE findings of the gastric corpus differed between H. pylori -associated and autoimmune gastritis, suggesting different pathogenesis of the two diseases.

Narrow band imaging under less-air condition improves the visibility of superficial esophageal squamous cell carcinoma

Background

The current virtual chromoendoscopy equipment cannot completely detect superficial squamous cell carcinoma (SCC) in the esophagus, despite its development in the recent years. Thus, in this study, we aimed to elucidate the appropriate air volume during endoscopic observation to improve the visibility of esophageal SCC.

Methods

This retrospective study included a total of 101 flat type esophageal SCCs identified between April 2017 and January 2019 at the Department of Gastrointestinal Oncology, Osaka International Cancer Institute. Video images of narrow band imaging (NBI) under both less-air and standard-air conditions were recorded digitally. Videos were evaluated by five endoscopists. Relative visibility between less-air and standard-air conditions of the brownish area, brownish color change of the epithelium, and dilated intrapapillary capillary loop (IPCL) were graded as 5 (definitely better under less-air condition) to 1 (definitely worse under less-air condition), with 3 indicating average visibility (equivalent to standard-air observation).

Results

The mean (standard deviation) visibility score of the brownish area, brownish color change of the epithelium, and dilated IPCLs under less-air condition were 3.94 (0.58), 3.73 (0.57), and 4.13 (0.60), respectively, which were significantly better than that under standard-air condition (p < 0.0001). Esophageal SCC evaluated as ≥ 4 in the mean visibility score of the brownish area, brownish color change of the epithelium, and dilated IPCLs accounted for 50% (51/101 lesions), 34% (34/101 lesions), and 67% (68/101 lesions), respectively.

Conclusions

The present results suggested that NBI with less air might improve the visibility of flat type esophageal SCC compared with NBI with standard air. Less-air NBI observation may facilitate the detection of flat type esophageal SCC.

Trial registration

The present study is a non-intervention trial.

Risk of recurrence when cutting into intramucosal (pT1a) cancer from the cutting-plane side during gastric endoscopic submucosal dissection

BACKGROUND

During endoscopic submucosal dissection (ESD), procedural difficulty and poor visibility of the cutting plane sometimes cause the operator to cut into the lesion from the cutting-plane side, making the vertical margin positive (VM1) or unclear (VMX). In the present study, we evaluated the risk of recurrence of gastric cancer with VM1 /VMX after ESD.

METHODS

In total, 1723 consecutive gastric cancers treated by ESD at Osaka International Cancer Institute from July 2012 to December 2017 were included in this retrospective cohort study. Among them, 231 submucosal or more deeply invasive gastric cancers were excluded because nontechnical factors may contribute to VM1 /VMX in such lesions. To quantify the risk of cutting into cancer from the cutting-plane side during ESD, the proportion of lesions with VM1 /VMX among the pT1a gastric cancers treated by ESD was calculated. The proportion of recurrence among these cases was calculated after exclusion of lesions with positive lymphovascular invasion or a positive horizontal margin in order to eliminate the obvious risk factors for recurrence.

RESULTS

Among 1492 pT1a gastric cancers treated by ESD, 28 lesions (1.9 %; 95 % confidence interval [CI] 1.3 % - 2.7 %) histologically showed VM1 /VMX. No local recurrence (0.0 %; 95 %CI 0.0 % - 12.2 %) occurred among 23 cases. The median follow-up period was 41 months (range 10 - 84 months).

CONCLUSIONS

No local recurrence was detected in pT1a gastric cancers after VM1 /VMX resection by ESD. Surveillance endoscopy could be adopted for such cases without additional surgery.

Usefulness of epinephrine-added injection solution to reduce procedure time for gastric endoscopic submucosal dissection

Background and study aims  Epinephrine-added submucosal injection solution is used to facilitate hemostasis of non-variceal upper gastrointestinal bleeding and to prevent delayed bleeding of large pedunculated colorectal lesions. However, its benefit in gastric endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) is unclear. The effectiveness of epinephrine-added injection solution for outcomes of gastric ESD was examined using propensity score matching analysis. Patients and methods  A total of 1,599 patients with solitary EGC (83 with non-epinephrine-added solution and 1,516 with epinephrine-added solution) between 2011 and 2018 were enrolled. Propensity scores were calculated to balance the distribution of baseline characteristics: age, sex, tumor location, specimen size, presence of ulcer scar, tumor depth, histological tumor type, and operators' experience, and 1:3 matching was performed. En bloc resection rate, mean procedure time, delayed bleeding rate, and perforation rate were compared between the non-epinephrine (n = 79) and epinephrine (n = 237) groups. Results  Mean procedure time was significantly shorter in the epinephrine group than in the non-epinephrine group (60 vs. 78 min, P  < 0.001). No significant difference was found in the rate of en bloc resection (both 99 %), incidence of delayed bleeding (both 6 %), or perforation (0 vs. 0.8 %) between the two groups. In multiple linear regression analysis, use of epinephrine-added solution was independently associated with short procedure time ( P  < 0.001) after adjustment for other covariates. Conclusion  The results suggest that epinephrine-added injection solution is useful for reduction of gastric ESD procedure time, warranting validation in a randomized controlled trial.

Features of Esophageal Adenocarcinoma in Magnifying Narrow-Band Imaging

BACKGROUND

Several endoscopic classifications for esophageal adenocarcinoma have been proposed; however, gastric adenocarcinoma is much more common than esophageal or esophagogastric junctional (EGJ) adenocarcinoma in East Asian countries. We, therefore, investigated whether an endoscopic diagnostic algorithm for gastric adenocarcinoma could be used for esophageal or EGJ adenocarcinoma.

METHODS

One hundred eighteen consecutive patients who underwent endoscopic resection or surgery for intramucosal esophageal or EGJ adenocarcinoma, at the Osaka International Cancer Institute between January 2006 and December 2017, were included in this retrospective study. Their lesions were classified as Siewert type 1 or 2, and the presence of endoscopic magnifying narrow-band imaging findings for diagnosing gastric adenocarcinoma was evaluated.

RESULTS

We evaluated 125 adenocarcinomas in 118 patients (29 type 1 and 96 type 2). Demarcation lines (DLs) were seen in 7 (24%) type 1 and 53 (55%) type 2 lesions. Irregular mucosal patterns were present in 2 (7%) type 1 and 22 (23%) type 2 lesions. Irregular vascular patterns were present in 26 (90%) type 1 and 50 (52%) type 2 lesions. According to the magnifying endoscopy diagnostic algorithm for gastric adenocarcinoma, only 7 (24%) type 1 and 52 (54%) type 2 lesions were correctly diagnosed as cancers (p = 0.005).

CONCLUSION

The magnifying endoscopy diagnostic algorithm for gastric cancer may not be useful for esophageal or EGJ adenocarcinomas because of the low visibility of DLs, especially in Siewert type 1 adenocarcinoma.

Feasibility of underwater endoscopic mucosal resection and management of residues for superficial non-ampullary duodenal epithelial neoplasms

BACKGROUND AND AIM

Underwater endoscopic mucosal resection (UEMR) is effective for superficial non-ampullary duodenal epithelial neoplasms (SNADEN). However, the incidence of residual lesion after UEMR, especially for large lesions (≥20 mm), and their prognosis remain unclear. We aimed to assess the incidence of residual lesions and further outcomes after UEMR for SNADEN.

METHODS

We carried out a retrospective study at a tertiary cancer institute. Candidates for the study were systematically retrieved from an endoscopic and pathological database from January 2013 to April 2018.

RESULTS

A total of 162 SNADEN resected with UEMR were analyzed. Median (range) procedure time was 5 (1-70) min. En bloc resection rates for large lesions (≥20 mm) and small lesions (<20 mm) were 14% and 79%, respectively. Intraprocedural bleeding occurred in one (0.6%) case, but no intraprocedural perforation occurred during the study. Delayed bleeding occurred in two (1.2%) cases and delayed perforation occurred in one (0.6%) case. A total of 157 (97%) lesions were followed up by at least one endoscopic examination. Of these lesions, residual lesions were recognized in seven cases (5%). Additional UEMR was carried out in five lesions and underwater cold snare polypectomy in one lesion. One lesion was observed without additional treatment. After salvage intervention, no cases experienced further residual lesions.

CONCLUSION

Although UEMR for SNADEN can be relevant when other efficacious procedures are unavailable, careful follow up for residual lesions is required especially after piecemeal resection for large lesions.

Does cold snare polypectomy completely resect the mucosal layer? A prospective single-center observational trial

BACKGROUND AND AIM

The true incidence of incomplete muscularis mucosa resection with cold snare polypectomy (CSP) is unknown. We examined the incidence of incomplete muscularis mucosa resection both with and without cold snare defect protrusion (CSDP).

METHODS

We prospectively enrolled patients undergoing polypectomy for 4 to 9mm nonpedunculated polyps. We evaluated the presence of CSDP immediately following CSP and biopsied the CSDP or the center of the mucosal defect without CSDP. The presence of the muscularis mucosa and any residual polyp in the biopsies was evaluated histologically. The primary outcome was the incidence of incomplete mucosal layer resection defined as the presence of muscularis mucosa or residual polyp in the biopsies.

RESULTS

From August 2017 to October 2018, 188 patients were screened, and 357 polyps were included. CSDP was detected in 122/355 (34%) evaluated mucosal defects. Excluding five lesions requiring hemostasis immediately following CSP, 352 mucosal defects were biopsied. After excluding 102 biopsies containing normal mucosa, we evaluated 250 biopsies. The overall incidence of incomplete mucosal layer resection was 63% (159/250), 76% (68/90) with CSDP and 57% (91/159) without CSDP (P < 0.01). Both univariate and multivariate analyses showed that size (≥ 6 mm), resection time (≥ 5 s), and serrated lesions were risk factors for CSDP.

CONCLUSIONS

Cold snare defect protrusion (CSDP), which was present with 36%, was a good indicator for incomplete mucosal layer resection. Even in nonCSDP polypectomies, 57% of the mucosal layer was not removed completely. Thus, CSP should be used for intra-epithelial lesions only, and careful pretreatment evaluation is recommended.

Differentiation between duodenal neoplasms and non-neoplasms using magnifying narrow-band imaging - Do we still need biopsies for duodenal lesions?

OBJECTIVES

Endoscopic biopsies for nonampullary duodenal epithelial neoplasms (NADENs) can induce submucosal fibrosis, making endoscopic resection difficult. However, no biopsy-free method exists to distinguish between NADENs and non-neoplasms. We developed a diagnostic algorithm for duodenal neoplasms based on magnifying endoscopy findings and evaluated the model's diagnostic ability.

METHODS

Magnified endoscopic images and duodenal lesion histology were collected consecutively between January 2015 and April 2016. Diagnosticians classified the surface patterns as pit, groove or absent. In cases of nonvisible surface patterns, the vascular pattern was evaluated to determine regularity or irregularity. The correlation between our algorithm (pit-type or absent with irregular vascular pattern) and the lesion histology were evaluated. Four evaluators, who were blinded to the histology, also classified the endoscopic findings and evaluated the diagnostic performance and interobserver agreement.

RESULTS

Endoscopic images of 114 lesions were evaluated (70 NADENs and 44 non-neoplasms, 31 in the superior and 83 in the descending and horizontal duodenum). Of the NADEN surface patterns, 88% (62/70) were pit-type, while 79% (35/44) of the non-neoplasm surface patterns were groove-type. Our diagnostic algorithm for differentiating NADENs from non-neoplasms was high (sensitivity 96%, specificity 95%) in the descending and horizontal duodenum. The evaluators' diagnostic performances were also high, and interobserver agreement for the algorithm was good between each diagnostician and evaluator (κ = 0.60-0.76).

CONCLUSION

Diagnostic performance of our algorithm sufficiently enabled eliminating endoscopic biopsies for diagnosing the descending and horizontal duodenum.

Stratification of gastric cancer risk using a deep neural network

Background and Aim

Stratifying gastric cancer (GC) risk and endoscopy findings in high‐risk individuals may provide effective surveillance for GC. We developed a computerized image‐ analysis system for endoscopic images to stratify the risk of GC.

Methods

The system was trained using images taken during endoscopic examinations with non‐magnified white‐light imaging. Patients were classified as high‐risk (patients with GC), moderate‐risk (patients with current or past Helicobacter pylori infection or gastric atrophy), or low‐risk (patients with no history of H. pylori infection or gastric atrophy). After selection, 20,960, 17,404, and 68,920 images were collected as training images for the high‐, moderate‐, and low‐risk groups, respectively.

Results

Performance of the artificial intelligence (AI) system was evaluated by the prevalence of GC in each group using an independent validation dataset of patients who underwent endoscopic examination and H. pylori serum antibody testing. In total, 12,824 images from 454 patients were included in the analysis. The time required for diagnosing all the images was 345 seconds. The AI system diagnosed 46, 250, and 158 patients as low‐, moderate‐, and high risk, respectively. The prevalence of GC in the low‐, moderate‐, and high‐risk groups was 2.2, 8.8, and 16.4%, respectively (P = 0.0017). Three experienced endoscopists also successfully stratified the risk; however, interobserver agreement was not satisfactory (kappa value of 0.27, indicating fair agreement).

Conclusion

The current AI system detected significant differences in the prevalence of GC among the low‐, moderate‐, and high‐risk groups, suggesting its potential for stratifying GC risk.

Endoscopic appearance of esophageal xanthoma

Background and study aims  Esophageal xanthomas are considered to be rare, and their endoscopic diagnosis has not been fully elucidated. The aim of the present study was to determine the characteristics of the endoscopic appearance of esophageal xanthomas. Patients and methods  This was a retrospective study of consecutive patients with histologically diagnosed esophageal xanthomas at a referral cancer center in Japan. The endoscopic appearance, by magnifying or image-enhanced endoscopy, and histological findings of esophageal xanthomas were investigated. Results  Seven patients (six men and one woman) were enrolled. All of the patients had a solitary lesion, and the median size was 2 mm (range, 1 - 5 mm). Conventional white-light endoscopy showed the lesions as flat areas with yellowish spots in four cases and slightly elevated yellowish lesions in three cases. Magnifying endoscopy, performed in six patients, revealed the lesions as areas with aggregated minute yellowish spots with tortuous microvessels inside. Magnifying narrow-band imaging contrasted the yellowish spots and microvessels better than white-light endoscopy. In all lesions, histological examination showed that the yellowish spots corresponded to papillae filled with foam cells. The foam cells were strongly immunopositive for CD68, and in all lesions, CD34-positive intrapapillary capillaries surrounded the aggregated foam cells. The different morphologies of the flat and slightly elevated lesions corresponded to different densities of papillae filled with foam cells. Conclusions  Magnifying endoscopy revealed minute yellowish spots with tortuous microvessels inside. These correspond well with histological findings and so may be useful in the diagnosis of esophageal xanthomas.

Endoscopic full-thickness resection of gastric gastrointestinal stromal tumor: a Japanese case series

Background:

Gastrointestinal stromal tumors (GISTs) are potentially malignant and are indicated for resection. The standard treatment for resectable GISTs is surgery, although endoscopic resection has been reported outside Japan. This study retrospectively analyzed the results of endoscopic resection of GISTs in Japan.

Method:

We identified patients with GISTs treated only by endoscopic resection in our institute between January 2016 and December 2018, and analyzed their clinical and pathological characteristics.

Results:

During the study period, 8 GISTs were resected only by endoscopy: 7 were located in the upper third of the stomach and 1 in the middle. All were intraluminal growth type. Median (range) tumor diameter was 20 (10-35) mm. All tumors were resected en bloc with a median (range) operation time of 67.5 (50-166) min. Complete perforation occurred in 5 cases, but the serosa remained in 2 and the outer layer of the muscularis propria remained in 1. The defect was endoscopically closed with clip-and-endoloop purse-string suturing (n=3), simple endoclipping (n=2), or over-the-scope clipping (n=2), and 1 did not require closure because the outer longitudinal muscle was preserved. Oral feeding was commenced on postoperative day (POD) 3 (median; range 2-4), and the patient was discharged on POD 6 (median; range 4-11). No serious adverse event developed after the procedures.

Conclusion:

Endoscopic resection for selected cases of small intraluminal GISTs is feasible, making it a viable alternative treatment option to laparoscopic surgery.

Time trends in the incidence of esophageal adenocarcinoma, gastric adenocarcinoma, and superficial esophagogastric junction adenocarcinoma

BACKGROUND

In Japan, the incidence of esophageal adenocarcinoma (EAC) and esophagogastric junction (EGJ) adenocarcinoma is expected to increase and that of gastric adenocarcinoma (GAC) is expected to decrease due to Westernization of the diet and the decreasing prevalence of Helicobacter pylori infection. However, few reports about these trends have included the latest data, and no reports about the time trend in the incidence of EGJ adenocarcinoma have focused on the etiologies (gastric cardia adenocarcinoma or EAC, including Barrett's adenocarcinoma). We therefore investigated the time trends in the incidence of these cancers by including the latest data.

METHODS

First, we investigated the time trends in EAC and GAC using population-based cancer registry data in Osaka Prefecture (1985-2014). We then investigated the time trend in superficial EGJ adenocarcinoma with clinicopathological features at Osaka International Cancer Institute (2006-2017).

RESULTS

From 1985 to 2014 in Osaka Prefecture, the incidence of EAC gradually increased in both sexes, while that of GAC in men did not significantly change and that in women decreased. The ratio of the EAC/GAC incidence increased 3.5 times in men and 1.8 times in women. In the secondary time trend survey for EGJ adenocarcinoma, the numbers of patients with endoscopic Barrett's esophagus and those without gastric mucosal atrophy increased, and the number of patients with lesions located above the EGJ line and histologically diagnosed as Barrett's adenocarcinoma increased.

CONCLUSIONS

The incidence of EAC and superficial EGJ adenocarcinoma with characteristics similar to those of EAC, including Barrett's adenocarcinoma, might be increasing.

Effect of horizontal margin status and risk of local recurrence after endoscopic submucosal dissection for superficial esophageal cancer

Background and Aim

Endoscopic submucosal dissection (ESD) sometimes results in en bloc resection with a positive or inconclusive horizontal margin (HM1 or HMX, respectively) on histological evaluation. The specific risk for such situations is unclear. We therefore investigated the outcome of ESD with HM1 or HMX.

Methods

This single‐center retrospective study was performed at Osaka International Cancer Institute. A total of 886 esophageal squamous cell carcinoma lesions in 749 patients treated from April 2005 to June 2015 were evaluated according to the following inclusion criteria: en bloc resection with no residual lesion, HM1 or HMX status, no prior treatment, and no additional treatment. We classified HM1 and HMX into type A, in which cancer was exposed on the HM, and type B, in which the HM status was unclear because of mechanical or thermal damage. We further classified type B according to the distance between the cancer and the edge of the specimen: type B1, <1 mm and type B2, ≥1 mm.

Results

The resection margin was judged as HM1 or HMX in 5.0% (39/767; 95% confidence interval, 3.5–6.6%) of the en bloc resected specimens. Of 39 lesions, 30 fulfilled the inclusion criteria. Local recurrence developed in 8 of 30 lesions (26.7%). The local recurrence rates for types A, B1, and B2 were 40% (6/15 lesions), 28.5% (2/7 lesions), and 0.0% (0/8 lesions), respectively.

Conclusions

Although a statistical analysis was not conducted because of the limited events, the pathological HM status may be a useful predictor of local recurrence.

Pharyngeal observation via transoral endoscopy using a lip cover-type mouthpiece

BACKGROUND AND AIM

Simultaneous and metachronous head and neck cancers are likely to develop in patients with current or previous esophageal cancer. The Valsalva maneuver facilitates the visualization of the hypopharyngeal area during endoscopic observation, but it requires transnasal endoscopy. We developed a novel Valsalva maneuver using transoral endoscopy with a lip cover-type mouthpiece.

METHODS

Between March 2018 and July 2018, 107 patients with current or previous esophageal cancer who were scheduled to undergo upper gastrointestinal endoscopy were included in our pilot study. We performed the Valsalva maneuver using our newly developed mouthpiece and transoral endoscopy in the patients and evaluated the hypopharyngeal region, including the postcricoid area and the posterior wall of the hypopharynx. The outcome measure was procedural success rate, which was graded as "complete," "incomplete," and "none."

RESULTS

Observation of the hypopharyngeal area was "complete" in 81 patients (76%) using the Valsalva maneuver. However, in 25 patients and in 1 patient, observation was "incomplete" and "none," respectively. Seven lesions were newly detected in seven patients during the study period.

CONCLUSIONS

The Valsalva maneuver using transoral endoscopy with a lip cover-type mouthpiece is feasible for the visualization of the postcricoid area and the posterior wall of the hypopharynx. Particularly, this technique would contribute to early detection of head and neck cancers.

Pulley Traction-Assisted Colonic Endoscopic Submucosal Dissection: A Retrospective Case Series

BACKGROUND AND STUDY AIMS

We have reported the usefulness of traction-assisted colorectal endoscopic submucosal dissection (TAC-ESD) to overcome the technical difficulty of colorectal ESD. However, the direction of traction is toward the anal side only. We retrospectively evaluate the safety and efficacy of "pulley" TAC-ESD.

PATIENTS AND METHODS

We retrospectively analyzed patients diagnosed with colorectal polyps and treated by "pulley" TAC-ESD at Osaka International Cancer Institute from December 2017 to June 2018.

RESULTS

During the study period, 79 patients with 81 lesions were treated by ESD, and 54 of these patients were treated by traction-assisted ESD. Among them, 7 underwent "pulley" traction-assisted ESD (6 men, 1 woman; age, 48-69 years), resulting in en bloc resection with no complications. This afforded good visibility of the submucosal layer in 6 patients, but it was not effective in the remaining patient with the muscle-retracting sign.

CONCLUSION

The "pulley" method affords good visibility of the submucosal layer by changing the traction direction in cases that are difficult to manage by conventional traction-assisted ESD.

Endoscopic findings corresponding to multiple Lugol-voiding lesions in the esophageal background mucosa

BACKGROUND AND AIM

Multiple Lugol-voiding lesions (LVLs) on Lugol chromoendoscopy can predict the development of metachronous multiple cancers in the esophagus and the head and neck regions. However, Lugol chromoendoscopy sometimes causes adverse events such as chest pain and discomfort. We therefore investigated the endoscopic findings on narrow band imaging (NBI) or blue laser imaging (BLI) that correspond to the presence of multiple LVLs in patients with esophageal squamous cell carcinoma.

METHODS

First, we investigated the NBI/BLI findings corresponding to individual small LVLs (one-to-one correspondence). Second, we investigated the association between the grade of multiple LVLs and the five endoscopic findings, including multiple foci of dilated vessels (MDV), multiple small brownish areas without microvascular irregularity, and a nonuniform color tone.

RESULTS

One-to-one correspondence of endoscopic findings was analyzed in 106 small LVLs. The main findings matched with small LVLs were a focus of dilated vessels (44 lesions), a small brownish area (17 lesions), and a small brownish area with a focus of dilated vessels (19 lesions). The relationship between multiple LVLs and each finding assessed by NBI/BLI was assessed in 155 patients. Multivariate logistic regression indicated that the presence of MDV was the only finding independently associated with multiple LVLs (P < 0.01).

CONCLUSIONS

The presence of MDV in the noncancerous background esophageal mucosa was significantly associated with multiple LVLs. This pilot study demonstrates that MDV has the potential to be a new risk factor for the development of metachronous multiple esophageal squamous cell carcinoma.

Efficacy of vonoprazan in prevention of bleeding from endoscopic submucosal dissection-induced gastric ulcers: a prospective randomized phase II study

BACKGROUND

Vonoprazan, potassium-competitive acid blocker, is expected to reduce incidence of delayed bleeding after gastric endoscopic submucosal dissection (ESD); however, preliminary data to design a large-scale comparative study are lacking. This study aimed to assess the efficacy of vonoprazan in preventing delayed bleeding after gastric ESD.

METHODS

In this single-center randomized phase II trial, a modified screened selection design was used with a threshold non-bleeding rate of 89% and an expected rate of 97%. In this design, Simon's optimal two-stage design was first applied for each parallel group, and efficacy was evaluated in comparison with the threshold rate using binomial testing. Patients were randomly assigned in a 1:1 ratio to receive either vonoprazan 20 mg (VPZ group) or lansoprazole 30 mg (PPI group) for 8 weeks from the day before gastric ESD. The primary endpoint was the incidence of delayed bleeding, defined as endoscopically confirmed bleeding accompanied by hematemesis, melena, or a decrease in hemoglobin of ≥ 2 g/dl.

RESULTS

Delayed bleeding occurred in three of 69 patients (4.3%, 95% CI 0.9-12.2%, p = 0.047) in the VPZ group, and four of 70 (5.7%, 95% CI 1.6-14.0%, p = 0.104) in the PPI group. As only vonoprazan showed significant reduction in delayed bleeding compared with the threshold rate, it was determined to be efficacious treatment.

CONCLUSIONS

Vonoprazan efficaciously reduced the delayed bleeding rate in patients with an ESD-induced gastric ulcer. A large-scale, randomized, phase III study is warranted to definitively test the effectiveness of vonoprazan compared with proton pump inhibitors.