Safety and Efficacy of Self-Expandable Metallic Stent Placement Using Low Radial Force Stent for Malignant Dysphagia after Radiotherapy.

INTRODUCTION: We aimed to investigate the safety and efficacy of self-expandable metallic stent (SEMS) placement in patients with prior radiotherapy (RT) using the Niti-S stent, which is characterized by low radial force, in comparison to patients without prior RT. METHODS: A consecutive series of 83 patients who were treated by SEMS placement using Niti-S stent for severe malignant esophageal obstruction or fistula were enrolled. The adverse event rates and efficacy were retrospectively compared between patients with/without prior RT before SEMS placement (RT group [n = 32] versus non-RT group [n = 51]). RESULTS: The incidence rate of major adverse events in the RT group was 6.3% and was not significantly different from that in the non-RT group (5.9%, p = 0.95). Among the RT group, 84.4% were able to resume oral intake within a median of 2 days. Among the patients with fistula, 78.6% could resume oral intake and survive for 73 days after SEMS placement. Cox proportional hazard regression analysis identified significant factors affecting overall survival to be prior RT (hazard ratio [HR]: 1.96), low performance status (HR: 3.87), and subsequent anticancer treatment after SEMS placement (HR: 0.41). However, compared to the non-RT group, the RT group had received longer duration of anticancer treatment before SEMS placement and a lower rate of subsequent anticancer treatment after SEMS placement. CONCLUSIONS: With the Niti-S stent, the incidence of major adverse events was sufficiently low even for patients after RT. SEMS with low radial force would be an effective palliative treatment option for patients, regardless of prior RT.

Ability of artificial intelligence to detect T1 esophageal squamous cell carcinoma from endoscopic videos and the effects of real-time assistance.

Diagnosis using artificial intelligence (AI) with deep learning could be useful in endoscopic examinations. We investigated the ability of AI to detect superficial esophageal squamous cell carcinoma (ESCC) from esophagogastroduodenoscopy (EGD) videos. We retrospectively collected 8428 EGD images of esophageal cancer to develop a convolutional neural network through deep learning. We evaluated the detection accuracy of the AI diagnosing system compared with that of 18 endoscopists. We used 144 EGD videos for the two validation sets. First, we used 64 EGD observation videos of ESCCs using both white light imaging (WLI) and narrow-band imaging (NBI). We then evaluated the system using 80 EGD videos from 40 patients (20 with superficial ESCC and 20 with non-ESCC). In the first set, the AI system correctly diagnosed 100% ESCCs. In the second set, it correctly detected 85% (17/20) ESCCs. Of these, 75% (15/20) and 55% (11/22) were detected by WLI and NBI, respectively, and the positive predictive value was 36.7%. The endoscopists correctly detected 45% (25-70%) ESCCs. With AI real-time assistance, the sensitivities of the endoscopists were significantly improved without AI assistance (p < 0.05). AI can detect superficial ESCCs from EGD videos with high sensitivity and the sensitivity of the endoscopist was improved with AI real-time support.

Therapeutic outcomes of endoscopic resection for superficial non-ampullary duodenal tumor.

BACKGROUND AND AIM: Endoscopic resection (ER) is widely used as a minimally invasive therapy to remove superficial non-ampullary duodenal tumor (SNADT). However, the indication criteria have not yet been clearly determined. At our institute, ER is done only for SNADT measuring ≤ 20 mm. We report our findings on the therapeutic outcomes of ER of SNADT. METHODS: We carried out ER in 47 patients with SNADT. Indication criteria for ER included a lesion suspected as high-grade dysplasia or mucosal cancer and measuring ≤ 20 mm. The ER methods used to carry out en bloc resection were endoscopic mucosal resection (EMR: 17 lesions) or endoscopic submucosal dissection (ESD: 30 lesions). We then analyzed the therapeutic outcomes between them. RESULTS: There were no significant differences between the EMR and ESD groups with regard to age, sex, location of the lesion, and histology. The most frequent gross types resected by EMR and ESD were 0-IIa and 0-IIc, respectively (P=0.004). Median procedure time was significantly longer in ESD than in EMR, 79.5 and 9 min, respectively (P<0.001). R0 resection was achieved in 10 cases by EMR (59%) and in 27 cases by ESD (90%) (P=0.017). No complications occurred in cases that underwent EMR, but immediate and delayed perforations occurred in three patients who underwent ESD, although this difference was not statistically significant (P=0.467). CONCLUSION: Using our indication criteria, which limited lesion size to ≤ 20 mm, satisfactory therapeutic outcomes of ER of SNADT were obtained.

Long-term release of a malignant ileal obstruction by placement of a colorectal self-expandable metal stent.

An 84-year-old man underwent the Hartmann procedure with an R1 resection for advanced rectal cancer. One year after surgery, the patient presented with abdominal pain and vomiting. Abdominal radiography and computed tomography revealed an expanding small bowel and ileal obstruction caused by invasion of local, recurrent rectal cancer. In order to release the ileal obstruction, a colorectal self-expandable metal stent was placed via a through-the-scope technique using a colonoscope inserted through a stoma in the transverse colon. After stent placement, the patient's clinical symptoms and signs improved and the symptoms of obstruction did not recur. No major complications associated with the placement of the stent were observed during the 7-month follow-up period. Thus, self-expandable metal stents are a safe and effective palliative treatment for malignant gastroduodenal or colorectal obstructions, and as a bridge to surgery. However, endoscopic placement of these stents in cases of malignant small bowel obstruction is not yet feasible because of the limitations of endoscopic access and the stent delivery system. To our knowledge, this is the first report of malignant ileal obstruction treated with a colorectal self-expandable metal stent using a colonoscope. This case indicates that colorectal self-expandable metal stents can be effectively and safely used to treat malignant ileal obstructions.

Extensive 0-IIc (undifferentiated carcinoma) lesion around a gastric adenoma: a case report.

A 73-year-old woman underwent esophagogastroduodenoscopy (EGD) at a local hospital, which revealed a flat elevated lesion, approximately 15 mm in diameter, in the posterior wall of the lower gastric body. At our hospital, a repeat EGD and biopsy led to a diagnosis of moderately dysplastic adenoma. The patient requested endoscopic submucosal dissection (ESD). Histopathology revealed a gastric adenoma with negativity for tumor at the vertical margin; however, the horizontal margin was positive for cancer with an undifferentiated carcinoma surrounding the adenoma. EGD was repeated, and a discolored area was found around the ESD scar. Biopsy revealed an undifferentiated carcinoma. Laparoscopic distal gastrectomy was performed, and postoperative histopathology also revealed an undifferentiated carcinoma (50 mm in diameter) surrounding the ESD scar; this lesion was an undifferentiated adenocarcinoma that was colocalized with and spread out to surround the original adenoma. This case is important for consideration of the pattern of development and progression of superficial spreading gastric cancer.

Safety, efficacy, and long-term outcomes for endoscopic submucosal dissection of early esophagogastric junction cancer.

BACKGROUND: Early esophagogastric junction (EGJ) cancer is currently being treated in the same way as early gastric cancer, by endoscopic submucosal dissection (ESD), but long-term outcomes are still unknown. Our aim was to retrospectively evaluate the safety and efficacy of ESD in treating early EGJ cancer and compare risk factors in curative and non-curative resection cases. METHODS: Forty-four cases of early EGJ cancer, defined as a Siewert's type II tumor, in 44 patients with a mean age of 70.0 years and a male/female ratio of 90.9:9.1 % were treated by ESD between January 2004 and June 2010. There were 30 standard indication cases; the remaining 14 cases were expanded indication cases. RESULTS: Mean resected specimen and tumor sizes were 35 and 17 mm, respectively, and median procedure time was 121 min, with no bleeding or perforation complications. All cases were resected en bloc with an 84.1 % curative resection rate (37/44). The curative resection rates in the standard and expanded indication cases were 90.0 % (27/30) and 71.4 % (10/14), respectively. There were no significant differences in tumor location, tumor morphology, tumor size, histology of biopsy specimens, or standard versus expanded indication cases with regard to risk factors for curative and non-curative resections. However, submucosal invasion, positive tumor margins, lymphovascular invasion, and some components of poorly differentiated adenocarcinomas in just the submucosal layer were significantly more common in the non-curative resection cases. CONCLUSIONS: ESD was a safe, effective, and minimally invasive treatment for early EGJ cancer. For tumors without any submucosal invasion findings, therefore, ESD is an acceptable treatment option, in addition to also being suitable for diagnostic purposes in evaluating the need for surgery.

Usefulness of sodium hyaluronate solution in colorectal endoscopic mucosal resection.

BACKGROUND: In endoscopic mucosal resection (EMR), it is essential to inject submucosal fluid to prevent complications and ensure safe and complete en bloc resection of tumors. Sodium hyaluronate (SH) solution, which is effective in forming and maintaining a mucosal lift and is innocuous to mucosal tissue, is considered a useful injection solution for endoscopic submucosal dissection, a procedure associated with a high risk of perforation. This study was undertaken to assess the usefulness of this solution in EMR. METHODS: Ninety-four patients with colorectal tumors of ≤20 mm in diameter were enrolled for this study and randomized to a SH solution group (0.2% two-fold diluted MucoUp) or to a normal saline group (control). Ease of EMR was primarily assessed based on ease of submucosal injection, ease of snaring and injection time. RESULTS: SH solution was superior to normal saline for ease of submucosal injection (57 ± 0.7 vs 50 ± 0.7; P < 0.05), and it showed better results for ease of snaring with less variability (63 ± 0.8 vs 51 ± 1.0; P < 0.05). The mean injection time was similar between the two groups (3.0 ± 9.0 s and 3.0 ± 2.7 s, respectively). Post-procedural hemorrhage occurred in 7% patients (3/46) injected with SH solution and in 6% of patients (3/48) in the control group; there was no significant difference between the groups. CONCLUSIONS: Use of two-fold diluted MucoUp facilitated colorectal EMR.