Comparison of hemostatic ability between spray coagulation and forced coagulation modes in endoscopic submucosal dissection in patients with early gastric neoplasms: a study protocol for multicenter randomized controlled trial (Spray-G trial).

BACKGROUND: Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric neoplasms (EGN). Controlling intraoperative bleeding is crucial for ensuring safe and reliable procedures. ESD using the spray coagulation mode (SCM-ESD) has been developed to control bleeding more effectively than ESD using the conventional forced coagulation mode (FCM-ESD). This study aims to compare the hemostatic efficacies of SCM-ESD and FCM-ESD. METHODS: This multicenter, prospective, parallel, randomized, open-label superiority trial will be conducted in five Japanese institutions. Patients with a preoperative diagnosis of intramucosal EGC will be randomized to undergo either SCM-ESD or FCM-ESD. The primary outcome measure is the completion of ESD with an electrosurgical knife alone, without the use of hemostatic forceps. Secondary outcomes include the number and duration of hemostasis using hemostatic forceps, procedure time, curability, and safety. A total of 130 patients will be enrolled in this study. DISCUSSION: This trial will provide evidence on the hemostatic efficacy of SCM-ESD compared with FCM-ESD in patients with intramucosal EGN, potentially improving the safety and reliability of ESD procedures. TRIAL REGISTRATION: The trial has been registered at the University Hospital Medical Information Network Clinical Trials Registration (UMIN-CTR) as UMIN000040518. The reception number is R000054009.

Desmin immunostaining is effective for improving interobserver variability in the depth assessment of the submucosal invasion of colorectal cancers.

Tumor depth evaluation is essential for pathological tumor staging because it affects clinical management as an independent risk factor for lymph node metastasis in colorectal cancers. However, poor interobserver variability of invasion depth has been reported. This study aimed to clarify the effectiveness of desmin immunostaining in the histological diagnosis of colorectal cancer. Overall, 63 sets of slides of colorectal cancer stained with hematoxylin and eosin (H&E) and desmin were prepared and independently reviewed by four examiners. After reviewing the desmin-stained slides, the interobserver variability of H&E slides alone was significantly improved for all examiners. For the assessment of Tis vs. T1, the sensitivity and accuracy were significantly improved for all examiners by combining H&E and desmin immunostaining. For the diagnosis of T1b vs. Tis or T1a, specificity and accuracy were significantly improved by adding desmin immunostaining. Ancillary desmin staining to assess submucosal invasion in colorectal cancers significantly improved interobserver agreement, led to efficient screening of T1 cancers, and reduced excessive T1b diagnoses. The combination of desmin immunostaining and H&E staining is highly recommended for diagnosing invasive colorectal cancer.

A novel, simple, and dedicated device for endoscopic mucosal defect closure.

Objectives: Endoscopic submucosal dissection (ESD) has become popular, but complications such as postoperative bleeding remain an issue. Although some methods of closing a mucosal defect with a snare and clips have been reported to be effective and safe, the snare is not a dedicated device, and the procedure is difficult and time-consuming. We aimed to find an alternative method for defect closure after ESD by developing a dedicated device. Methods: We have improved five prototypes. The load on the stopper when starting to tighten and loosen a loop and the maximum load on the stopper and the movement distance of the thread when sliding the stopper were measured five times for each prototype. With the 5th prototype, we finalized the design and named it FLEXLOOP. Additionally, the material and shape of the outer tube were improved. Then, the usability of FLEXLOOP was evaluated in pigs. The operation time for closing mucosal defects with the snare or FLEXLOOP was measured five times. Results: We made FLEXLOOP, which had a lower load when sliding and a higher load when loosening than the snare. The improvement of the outer tube significantly reduced the load on the sheath when sliding it. We confirmed the feasibility of mucosal defect closure with FLEXLOOP in pigs. The median operation time was 563 s (range 340-679 s) with the snare and 355 s (range 303-455 s) with FLEXLOOP (p = 0.047). Conclusions: FLEXLOOP can be a promising option for defect closure after ESD.

Indications of Endoscopic Submucosal Dissection for Undifferentiated Early Gastric Cancer: Current Status and Future Perspectives for Further Expansion.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a widely accepted and minimally invasive treatment for early gastric cancer (EGC) without the risk of lymph node metastasis (LNM). However, undifferentiated-type EGC (UD-EGC) is considered to have a relatively high risk of LNM. Recently, the Japan Clinical Oncology Group conducted a nonrandomized confirmatory trial (JCOG1009/1010) to evaluate the efficacy and safety of ESD for UD-EGC. Herein, we review the results of JCOG1009/1010 and the possibility of further expanding the indications for ESD. SUMMARY: JCOG1009/1010 showed excellent technical results and 5-year overall survival in patients with UD-EGC. Based on the results, ESD for UD-EGC (cT1a) of ≤2 cm without ulceration was technically feasible and acceptable for standard treatment instead of gastrectomy with lymph node dissection. A review of the EGC of mixed histological type (mixed EGC) suggested that the mixed EGC might have worse biological behavior than the pure histological type. In cases of intramucosal EGC with pure signet-ring cell carcinoma or presenting a double-layer structure, the risk of LNM might be relatively low. Thus, there is a possibility of further expanding the indications or curative evaluations. In the case of UD-EGC after noncurative resection, the data suggest that the eCura system may be applicable to UD-EGC; however, due to the small number of cases, further study is warranted. Key Message: This review summarizes the present knowledge regarding indications for UD-EGC and the possibility of further expanding them.

Endoloop closure following gastric endoscopic submucosal dissection to prevent delayed bleeding in patients receiving antithrombotic therapy.

OBJECTIVES: Given the high risk of bleeding in post-endoscopic submucosal dissection (ESD) patients receiving antithrombotic therapy, a new effective method is needed to prevent delayed bleeding among such patients. The aim of this study was to assess the efficacy of endoloop closure, using an endoloop and clips, after gastric ESD to prevent bleeding among patients receiving antithrombotic therapy. METHODS: This retrospective study enrolled patients taking antithrombotic agents who underwent ESD for early gastric cancer between March 2016 and January 2019. Patients were classified into two groups: the endoloop closure group and the control group (no prophylactic treatment). We compared the rates of post-endoscopic submucosal dissection bleeding between the two groups. RESULTS: Overall, 178 patients were included, with 37 patients in the endoloop closure group and 141 patients in the control group. The rate of post-endoscopic submucosal dissection bleeding was in general lower in the endoloop closure group than in the control group; however, the difference was not statistically significant (8% vs. 23%, p = 0.06). Among patients with a resected specimen size <40 mm and those using multiple antithrombotic agents, the endoloop closure group showed a lower rate of post-endoscopic submucosal dissection bleeding (0% vs. 16%, p = 0.03 and 10% vs. 70%, p = 0.02, respectively). CONCLUSIONS: Closure using an endoloop and endoclips after gastric ESD might prevent post-procedure bleeding in patients receiving antithrombotic therapy, particularly in those patients with a resected specimen <40 mm and those receiving multiple antithrombotic agents.

[Indications of Endoscopic Submucosal Dissection for Early Gastric Cancer].

Endoscopic submucosal dissection(ESD)has been established as a standard treatment for early gastric cancer with low possibility of lymph node metastasis. Based on the results of the multicenter prospective study(JCOG0607), expanded indication for differentiated-type gastric cancer in Gastric Cancer Treatment Guidelines 2014 changed to absolute indication in Gastric Cancer Treatment Guidelines 2018. The other multicenter prospective study(JCOG1009/1010)will reveal the longterm outcomes of ESD for undifferentiated-type gastric cancer. With the advance of an aging society in Japan, the indication and curability of early gastric cancer for elderly patients should be discussed in the future.