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.

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.

Usefulness of the ultrathin endoscope with a newly developed knife for complex esophageal endoscopic submucosal dissection.

Video 1Usefulness of an ultrathin endoscope with a newly developed knife for complex esophageal endoscopic submucosal dissection.

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.

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.

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).

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.

Utility of an artificial intelligence system for classification of esophageal lesions when simulating its clinical use.

Previous reports have shown favorable performance of artificial intelligence (AI) systems for diagnosing esophageal squamous cell carcinoma (ESCC) compared with endoscopists. However, these findings don't reflect performance in clinical situations, as endoscopists classify lesions based on both magnified and non-magnified videos, while AI systems often use only a few magnified narrow band imaging (NBI) still images. We evaluated the performance of the AI system in simulated clinical situations.

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.

Safety and efficacy of cold versus hot snare polypectomy including colorectal polyps ≥1 cm in size.

Cold snare polypectomy (CSP; polypectomy without electrocautery) has spread rapidly worldwide during the past decade in what has been called "Cold Revolution". We performed a PubMed literature search for studies investigating CSP outcomes for colorectal polyps. Five randomized controlled trials (RCTs) assessed the complete resection rates (CRRs).

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.

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.

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.

Validity of endoscopic resection for clinically diagnosed T1a-MM/T1b-SM1 N0 M0 esophageal squamous cell carcinoma.

Background: Previous guidelines have not described clear recommendations for performing endoscopic resection (ER) of T1a-muscularis mucosa (MM)/T1b-submucosal (SM1) cancers that have invaded ≤ 200 μm because these are considered to have a non-negligible risk of metastasis based on previous analyses of pathologically diagnosed (p)MM/SM1 cancers. Considering that the indication for ER is determined based on a clinical diagnosis, the applicability of ER should be investigated in clinical (c)MM/SM1 but not pMM/SM1 cancers. This study aimed to evaluate validity of ER for cMM/SM1 cancers.

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.

Real-time assessment of video images for esophageal squamous cell carcinoma invasion depth using artificial intelligence.

Background: Although optimal treatment of superficial esophageal squamous cell carcinoma (SCC) requires accurate evaluation of cancer invasion depth, the current process is rather subjective and may vary by observer. We, therefore, aimed to develop an AI system to calculate cancer invasion depth.

Methods: We gathered and selected 23,977 images (6857 WLI and 17,120 NBI/BLI images) of pathologically proven superficial esophageal SCC from endoscopic videos and still images of superficial esophageal SCC taken in our facility, to use as a learning dataset.

Diagnosis of pharyngeal cancer on endoscopic video images by Mask region-based convolutional neural network.

Objectives: We aimed to develop an artificial intelligence (AI) system for the real-time diagnosis of pharyngeal cancers.

Methods: Endoscopic video images and still images of pharyngeal cancer treated in our facility were collected. A total of 4559 images of pathologically proven pharyngeal cancer (1243 using white light imaging and 3316 using narrow-band imaging/blue laser imaging) from 276 patients were used as a training dataset.