The feasibility and safety of endoscopic submucosal dissection of gastric lesions larger than 5 cm.

BACKGROUND: As the indications for endoscopic submucosal dissection (ESD) for early gastric cancer have been revised, diagnostic ESD has increased. However, despite the technical difficulty of ESD for large lesions, the degree to which curative resection can be achieved has not been clarified. This study investigated the feasibility and safety of ESD for gastric lesions larger than 5 cm. METHODS: This retrospective multicenter study included 3474 gastric lesions treated by ESD from April 2012 to December 2021. We compared clinicopathological characteristics and treatment outcomes between lesions ≥ 5 cm and lesions < 5 cm. RESULTS: There were 128 lesions in the ≥ 5 cm group and 3282 lesions in the < 5 cm group. In the ≥ 5 cm group, upper location and fibrosis during ESD were more common, with a lower rate of 0-IIc type. Both en bloc resection rate and R0 resection rate were comparable, but there was a difference in curative resection rate (65.6% in the ≥ 5 cm group and 91.5% in the < 5 cm group). The frequency of adverse events (post-ESD bleeding, perforation, or stenosis) was almost similar, but delayed perforation was significantly more common (1.6% in the ≥ 5 cm group vs. 0.1% in the < 5 cm group). CONCLUSIONS: About two-thirds of curative resections were obtained with ESD for early gastric lesions larger than 5 cm, but delayed complications should be noted (Number: UMIN000047725).

Efficacy of hepatitis C virus eradication after curative treatment for hepatocellular carcinoma in patients with advanced hepatocellular carcinoma and decreased hepatic functional reserve: A nationwide, multicentre study by the Japanese Red Cross Liver Study Group.

Improvements in the hepatocellular carcinoma (HCC) recurrence rate and survival have been frequently reported following virus eradication after hepatitis C virus (HCV)-related HCC cure. However, the efficacy of direct-acting antiviral (DAA) therapy in patients who included those with advanced HCC and decreased hepatic functional reserve is unknown. A comparative examination was retrospectively conducted of 141 patients with hepatitis C who started DAA therapy within 1 year after undergoing curative HCC treatment and showed a sustained viral response (SVR) and 327 patients who underwent curative treatment for HCV-related HCC and did not subsequently receive antiviral therapy. Whether DAA therapy was given was identified as an independent factor related to both HCC recurrence and survival. Both the recurrence and survival rates improved significantly with DAA therapy in Child-Pugh (CP)-A, whereas no difference in the recurrence rate was seen with DAA therapy in CP-B. However, the survival rate was significantly higher in the DAA group in this class. Similarly, dividing the patients by the Milan criteria showed significant improvements in the recurrence rate and survival with DAA therapy in patients within the Milan criteria. Patients with HCC beyond the Milan criteria showed no difference in recurrence rates, but the DAA group tended to have higher survival rates. Thus, DAA after curative therapy for HCC can be expected to improve survival in patients with advanced HCC or decreased hepatic functional reserve. HCV should be aggressively eradicated in all patients eligible for curative treatment of HCC.

Evaluation of cold snare polypectomy for small pedunculated (Ip) polyps with thin stalks: a prospective clinical feasibility study.

BACKGROUND: Although the use of cold snare polypectomy (CSP) has spread rapidly, no prospective studies evaluating the safety of CSP for pedunculated (Ip) polyps have been carried out. AIM: We performed this study to provide an accurate evaluation of the safety of CSP for Ip polyps. METHODS: This is a prospective study (UMIN000035687). From January 2019 to February 2021, the safety of CSP for use on Ip polyps <10 mm with thin stalks was evaluated at our hospital. The primary outcome measure was the incidence of bleeding (delayed post-polypectomy bleeding (DPPB) and immediate bleeding). RESULTS: During the study period, 89 consecutive patients (including 92 colonoscopies and 114 polyps) were prospectively enrolled. The en-bloc resection rate was 100%. The rate of DPPB after CSP was 0%, however, DPPB after conversion to HSP occurred in 1 case (33.3% (1/3)). The rate of immediate bleeding during CSP was 28.9% (33/114). Polyps with diameters ≥6 mm (OR (95% CI): 2.77 (1.041-7.376); p = .041) were extracted as independent risk factors for immediate bleeding during CSP for Ip polyps. In all, 104 (91.2%) polyps were low-grade adenomas, and the percentage of cases with negative pathological margins was 96.5% (110/114). CONCLUSIONS: CSP for Ip polyps was safe and had good outcomes. We believe that Ip polyps could be included as an indication for CSP, and that CSP may become the next step in the 'cold revolution.' To confirm our results and verify CSP's inclusion in future guidelines, prospective, randomized studies are necessary.

Recurrence of gastric cancer caused by implantation of tumor cells after curative endoscopic submucosal dissection.

A 93-year-old female underwent curative endoscopic submucosal dissection (ESD) for intramucosal gastric cancer (70 mm in diameter) in the antrum. The lesion showed an irregularly villous structure covered with mucus. En bloc resection was performed. The large resected specimen induced a longitudinal laceration on the right wall of the esophagogastric junction (EGJ) during retrieval. Unavoidably, we segmented the specimen in the stomach to facilitate retrieval. Histopathological evaluation of the specimen revealed well-to-moderately differentiated tubular and papillary adenocarcinoma. A new elevated lesion (15 mm in diameter) was found at the gastric side of the EGJ laceration scar 6 months after the first ESD, necessitating a second resection with ESD. Endoscopic, histopathological, and immunohistochemical features of the new lesion resembled those of the antral lesion. We assessed the new lesion as a recurrence of cancer caused by implantation of tumor cells in the mucosal laceration after ESD.We experienced recurrence caused by implantation of tumor cells in a mucosal laceration after curative gastric ESD. Endoscopist should be aware of the risk of implantation after gastric ESD.

Evaluation of colorectal endoscopic submucosal dissection using a multifunctional snare: a prospective clinical feasibility study (with videos).

BACKGROUND AND AIMS: The number of colorectal endoscopic submucosal dissections (ESDs) for early colorectal cancer is expected to increase in the future; therefore, cost reduction is a clinically important issue. The SOUTEN snare (Kaneka Medics, Tokyo, Japan) is a novel multifunctional snare developed for hybrid ESD at a low price. If ESD can be performed safely using the SOUTEN snare, the same therapeutic effect can be obtained as with conventional ESD at a lower cost. The aim of this prospective, pilot, clinical feasibility study was to evaluate the safety and efficacy of ESD using the SOUTEN snare (SOUTEN-ESD). METHODS: From October 2018 to January 2019, 119 consecutive patients (121 ESD procedures, 137 colorectal neoplasms) were prospectively enrolled and treated by SOUTEN-ESD at NTT Medical Center Tokyo and Omori Red Cross Hospital. The outcomes of SOUTEN-ESD were evaluated. RESULTS: Among 137 neoplasms, SOUTEN-ESD was completed in all cases. No cases required conversion to hybrid ESD or to a dedicated ESD device. The mean procedure time was 26.1 ± 14.3 minutes. Both the en-bloc resection rate and R0 resection rate were 100%. The rate of perforation was 0%, the rate of delayed bleeding was 2.2%, and the rate of post-ESD coagulation syndrome was 2.9%. CONCLUSIONS: SOUTEN-ESD was safe and had good outcomes. Although further studies are required to examine indications for SOUTEN-ESD and confirm the results of this study, effective ESD with this novel knife is feasible. The SOUTEN snare is a realistic option for colorectal ESD. (Clinical trial registration number: UMIN 000034299.).

Management of Less Than 10-mm-Sized Pedunculated (Ip) Polyps with Thin Stalk: Hot Snare Polypectomy Versus Cold Snare Polypectomy.

BACKGROUND: Although the use of cold snare polypectomy (CSP) has spread rapidly, its safety for pedunculated (Ip) polyps remains controversial. In particular, the outcomes of hot snare polypectomy (HSP) and CSP for Ip polyps have not been previously compared. AIMS: This study evaluated whether the rate of delayed postpolypectomy bleeding (DPPB) after CSP for Ip polyps was higher than that after HSP for Ip polyps and compared other outcomes (the rates of immediate bleeding and pathological margins) between the HSP and CSP procedures. METHODS: A total of 5905 colorectal polyps in 4920 patients were resected at Omori Red Cross Hospital between October 2012 and June 2019. The polyps were divided into two groups: the HSP group (86 polyps, 64 patients) and the CSP group (102 polyps, 87 patients). The primary outcome measure was the incidence of DPPB. The secondary outcome measures were the incidences of immediate bleeding during the procedure and pathological margins of the resected specimen. RESULTS: The rate of immediate bleeding during CSP was significantly higher than that for the HSP group [38.2% (39/102) versus 3.5% (3/86); p < 0.001]. However, the rate of DPPB was significantly higher in the HSP group than in the CSP group [4.7% (4/86) versus 0% (0/102); p < 0.001]. The rate of DPPB after CSP was 0%. CONCLUSIONS: This is the first study to compare the outcomes of HSP and CSP for Ip polyps. CSP is safer than HSP for Ip polyps measuring < 10 mm in diameter.

Safety and efficacy of cold snare polypectomy for pedunculated (Ip) polyps measuring less than 10 mm in diameter.

BACKGROUND: Although cold snare polypectomy (CSP) has spread rapidly, it still remains controversial whether CSP is safe for pedunculated (Ip) polyps. PURPOSE: The aim of this study was to evaluate whether CSP for Ip polyps measuring less than 10 mm in diameter might be associated with an increased rate of delayed post-polypectomy bleeding (DPPB). METHODS: A total of 1641 colorectal polyps in 634 patients were resected at Omori Red Cross Hospital between April 2018 and December 2018. The polyps were divided into two groups depending on the morphology: the Ip group (90 polyps), and the non-Ip group (1551 polyps). RESULTS: Among the 1641 polyps, there was no case of DPPB, including in the Ip group. Immediate bleeding occurred in a total of 101 (6.2%) cases. Polyp location in the rectum (OR (95% CI), 3.61 (1.843-7.092); p < 0.001), polyp diameter ≥ 6 mm (OR (95% CI), 2.65 (1.702-4.132); p < 0.001), Ip morphology (OR (95% CI), 15.66 (9.262-26.49); p < 0.001), and treatment with antithrombotic agents (OR (95% CI), 2.18 (1.358-3.501); p = 0.0012) were identified as significant risk factors for immediate bleeding. CONCLUSIONS: This is the first study conducted to examine the safety of CSP for Ip polyps measuring less than 10 mm in diameter. CSP can be performed with a high level of safety even for Ip polyps. Based on our findings, we believe that Ip polyps could be included as an indication for CSP. However, prospective, randomized studies are necessary to confirm our results.

Risk factors for incomplete polyp resection after cold snare polypectomy.

BACKGROUND: Incomplete polyp resection (IPR) is recognized as a risk factor for interval colorectal cancer (ICC), and is, therefore, an important issue in polypectomy. Cold snare polypectomy (CSP) is a procedure that does not involve electrocautery and has no burn effect. Therefore, there is the possibility that the risk of ICC associated with IPR is higher in cases undergoing CSP than in those undergoing hot polypectomy. However, little is known about the risk factors for IPR after CSP. PURPOSE: Precise identification of the risk factors can lead to prevention of IPR after CSP. Therefore, we performed this observational study for accurate identification of the risk factors for IPR after CSP. METHODS: Medical records of a total of 501 patients with 1177 colorectal polyps that were resected at Omori Red Cross Hospital between October 2017 and March 2018 were retrospectively reviewed. The lateral and deep margins of the resected polyps were evaluated to check for the resection completeness. RESULTS: Among the 1177 polyp resections, 1163 were included in the final analysis. IPR was detected in 206 (17.7%) cases. Performance of the resection by a trainee (OR (95% CI) 1.87 (1.328-2.632); P < 0.001) was identified as an independent risk factor for IPR in patients undergoing CSP. CONCLUSIONS: Performance of the polypectomy by a trainee was identified as a significant risk factor for IPR in patients undergoing CSP. Prospective, randomized studies are necessary in the future to develop effective methods for the prevention/control of IPR after CSP.

Investigation of the Local Recurrence Rate after Colorectal Endoscopic Mucosal Resection: Is Incomplete Polyp Resection Really a Clinically Important Problem? Analysis of the Rationale for the "Resect and Discard" Strategy.

Background/Aims: The "Resect and Discard" strategy is a potentially useful strategy. At present, only the lesion size and accuracy of diagnosis are cited as considerations for clinical adoption of this strategy. On the other hand, histopathology of the resected specimens after Endoscopic Mucosal Resection (EMR) reveals often an unclear or positive-margin status, implying Incomplete Polyp Resection (IPR). If IPR indeed increased the risk of local recurrence, histopathological evaluation of the margin would be indispensable and clinical adoption of this strategy is difficult. The aim of this study is to verify the association between IPR and the risk of local recurrence. Methods: The 1872 polyps and 603 EMR cases in 597 patients who had EMR between May 2013 and May 2014 were enrolled. The local recurrence rate until 3 years after the EMR in cases with the target lesions of the "Resect and Discard" strategy was determined in the negative-margin and IPR groups. Results: The final analysis was performed using the data of 1092 polyps, and 222 were categorized into the IPR group. There were no cases of recurrence in either of the groups. Conclusion: This is the world's first report conducted to examine the correlation of IPR and the local recurrence rate for clinical practice of "Resect and Discard" strategy. There is the possibility that pathological evaluation of the margins after EMR in patients with small polyps can be skipped.

Safety of Cold Snare Polypectomy in Patients Receiving Treatment with Antithrombotic Agents.

BACKGROUND: With the aging of the population and rising incidence of thromboembolic events, the clinical use of antithrombotic agents is also increasing. There are few reports yet on the management of antithrombotic agent use in patients undergoing cold snare polypectomy (CSP). AIMS: The aim of this study was to evaluate whether continued administration of antithrombotic agents in patients undergoing CSP would be associated with an increased rate of delayed post-polypectomy bleeding (DPPB). METHODS: A total of 1177 colorectal polyps in 501 patients were resected at Omori Red Cross Hospital between October 2017 and March 2018. The polyps were divided into two groups depending on whether the patients received antithrombotic agent treatment or not: the antithrombotic group (911 polyps) and the no-antithrombotic group (266 polyps). RESULTS: Among the 1177 polyp resections, there was no case of DPPB, including in the antithrombotic group. Immediate bleeding occurred in a total of 63 (5.4%) cases. Polyp location in the rectum (OR (95% CI) 2.64 (1.223-5.679); p = 0.013), polyp size ≥ 6 mm (OR (95% CI) 4.64 (2.719-7.933); p < 0.001), polypoid growth pattern (OR (95% CI) 2.78 (1.607-4.793); p < 0.001), and antithrombotic agent use (OR (95% CI) 2.98 (1.715-5.183); p < 0.001) were identified as significant risk factors of immediate bleeding. CONCLUSIONS: Continued use of antithrombotic agents does not increase the risk of DPPB, even in those receiving multiple antithrombotic agents. Thus, it is safe to perform CSP even in multiple agent users. Prospective, randomized studies are necessary to confirm our results.

Does interferon-free direct-acting antiviral therapy for hepatitis C after curative treatment for hepatocellular carcinoma lead to unexpected recurrences of HCC? A multicenter study by the Japanese Red Cross Hospital Liver Study Group.

BACKGROUND AND AIM: This study aimed to elucidate whether interferon (IFN)-free direct-acting antiviral (DAA) therapy for hepatitis C after curative treatment of hepatocellular carcinoma (HCC) promotes HCC recurrence in a real-world large-scale cohort. METHODS: This multicenter study was conducted by the Japanese Red Cross Hospital Liver Study Group. This retrospective study analyzed 516 patients who underwent antiviral treatment for hepatitis C with either IFN (n = 148) or IFN-free DAA (n = 368) after curative HCC treatment; 78 IFN-treated patients and 347 IFN-free DAA-treated patients achieved sustained virological response (SVR). The recurrence rate of HCC was compared between the antiviral therapies. Logistic analysis and Cox proportional hazards analysis identified factors associated with early recurrence of HCC within 24 weeks of antiviral therapy and recurrence throughout the observation period, respectively. RESULTS: AFP at the completion of antiviral therapy, clinical stage of HCC, and non-SVR were independent factors associated with early recurrence of HCC. Among patients who had achieved SVR, the clinical stage of HCC and the level of AFP at completion of antiviral therapy were independent factors associated with early recurrence of HCC. For recurrence throughout the observation period in SVR patients, AFP at completion of antiviral therapy, duration between last HCC treatment to antiviral therapy, and the number of treatments were independent factors. There was no significant difference in the rate of early recurrence of HCC or recurrence throughout the observation period between IFN and IFN-free DAA treated patients. CONCLUSIONS: There were no differences in the early recurrence rate of HCC between patients who underwent IFN and those who underwent IFN-free DAA as antiviral therapies.

Evaluation of local tumor residue after percutaneous radiofrequency ablation therapy for hepatocellular carcinoma.

BACKGROUND/AIMS: This study's purpose was to compare the efficacy of CO2-enhanced ultrasonography (US) with that of Sonazoid-enhanced US and conventional US in detecting local tumor residue after percutaneous radiofrequency (RF) ablation therapy for hepatocellular carcinoma. MATERIALS AND METHODS: Between February 2009 and March 2010, 141 lesions of 121 hepatocellular carcinoma patients were treated by percutaneous RF ablation, and 22 tumor residues were detected in 22 patients by contrast-enhanced computed tomography. These 22 patients were examined by conventional US, Sonazoid-enhanced US (0.5 mL/body of Sonazoid, intravenous administration), and CO2-enhanced US (10 mL of CO2, hepatic arterial administration). RESULTS: Tumor residue was confirmed by CO2-enhanced US in all the 22 patients (sensitivity: 100%) in 19 of the 22 patients by Sonazoid-enhanced US (sensitivity: 86%; 3 lesions that were not detected by this modality were located deeper than the sonographic depth (p=0.0109)), and in 17 of the 22 patients by conventional US (sensitivity: 77%; 5 lesions that were not detected by this modality were smaller in terms of the sonographic tumor size (p=0.0278)). CONCLUSION: Although CO2-enhanced US requires angiography, it was superior to both Sonazoid-enhanced US and conventional US for detecting tumor residues, particularly deep-seated ones, after percutaneous RF ablation.

Effects of antiviral therapy for hepatitis C following treatment of hepatocellular carcinoma: survey findings of the Japanese Red Cross Liver Study Group.

AIM: To investigate, in a large number of cases at multiple institutions, the effects and limitations of antiviral therapy for hepatitis C following treatment of hepatocellular carcinoma (HCC) in clinical practice. METHODS: Retrospective analysis was performed of 112 patients who had received interferon (IFN) for treating hepatitis C following treatment of HCC and were registered with the Japanese Red Cross Liver Study Group. Factors that may influence recurrence and survival rates were investigated. RESULTS: Factors involved in prevention of recurrence were: surgical resection as HCC treatment, platelet and α-fetoprotein (AFP) levels prior to IFN administration, IFN adherence and post-IFN AFP level. Multivariate analysis showed post-IFN AFP level to be an independent factor. Factors involved in prolonging survival were: IFN adherence, IFN response (sustained viral response), pre-IFN alanine aminotransferase and AFP levels, post-IFN AFP level and absence of recurrence. Multivariate analysis showed absence of recurrence to be an independent factor. Although IFN adherence was involved in recurrence and survival, ribavirin adherence was not. IFN was suggested to be involved in preventing recurrence and improving survival due not only to its anti-viral effect, but also its antitumor effect. CONCLUSION: Although complete prevention of HCC recurrence is difficult, the most important factor affecting first recurrence is the AFP level at 6 months after the conclusion of antiviral treatment. The survival rate improves dramatically if the hepatitis C virus is eliminated, but the most important factor for improving survival is absence of recurrence.