A Novel One-Step Knife Approach Can Reduce the Submucosal Injection Time of Endoscopic Submucosal Dissection: A Single-Blinded Randomized Multicenter Clinical Trials

Background/AimsEndoscopic submucosal dissection (ESD) is a curative treatment modality for early gastric neoplasms; however, ESD can be a time-consuming process. To overcome this pitfall, we developed the one-step knife (OSK) approach, which combines an endoscopic knife and injection needle on a single sheath. We aimed to evaluate whether this approach could reduce the ESD procedure time.MethodsThis single-blinded randomized multicenter trial at four tertiary hospitals from June 2019 to June 2020 included patients aged 19 to 85 years undergoing ESD. Patients were randomly assigned to two groups (OSK or conventional knife [CK]). The injection time, total procedure time, resected specimen size, submucosal fluid amount, degree of device satisfaction, and adverse events were evaluated and compared between groups.ResultsFifty-one patients were analyzed (OSK 25 patients and CK 26 patients). No baseline differences were observed between groups, with the exception of a higher portion of males in the OSK group. The mean injection time was significantly reduced in the OSK group (39.0 seconds) compared to that in the CK group (87.5 seconds, p<0.001). A decrease of more than 10 minutes in the total procedure time (18.0 minutes vs 28.1 minutes, p=0.055) in the OSK group compared to the CK group was observed. Second-look esophagogastroduodenoscopy revealed two delayed bleeding cases in the OSK group that were easily controlled by endoscopic hemostasis.ConclusionsOSK reduced the injection time and showed a decrease in total procedure time compared with the CK approach. OSK can be a feasible tool for ESD, especially in difficult cases.     

Multicenter Analysis of Clinicopathologic Features of Intraductal Papillary Mucinous Tumor of the Pancreas: Is It Possible to Predict the Malignancy Before Surgery?

Background Despite recently increasing numbers of reports on intraductal papillary mucinous tumors (IPMTs), difficulties still remain in terms of diagnosis, treatment, and prognosis. The purpose of this multicenter study was to evaluate the clinicopathologic features of IPMT in Korea and to suggest predictive criteria for malignancy in IPMT.Methods We retrospectively reviewed the clinicopathologic data of 208 patients who underwent operations for IPMT between 1993 and 2002 at 28 institutes in Korea.Results Of the 208 patients (mean age, 61 years), 147 were men and 61 were women. A total of 124 patients underwent pancreatoduodenectomy, 42 underwent distal pancreatectomy, 17 underwent total pancreatectomy, and 25 underwent limited pancreatic resection. There were 128 benign cases (adenoma, n = 62; borderline, n = 66) and 80 malignant cases (noninvasive, n = 29; invasive, n = 51). A significant difference in 5-year survival was observed between the benign and malignant groups (92.6% vs. 65.3%; P = .006). Of the six factors (age, location, duct dilatation, mural nodule, main duct type, and tumor size) that showed statistical differences by univariate analysis between the benign and malignant groups, three were significant by multivariate analysis—namely, mural nodule (P = .009), tumor size (P = .023), and a dilated duct size (P = .010).Conclusions A significant proportion of IPMTs are malignant, although the overall prognosis of IPMT is superior to that of ordinary pancreatic cancer. Radical surgery is recommended for IPMT with the predictors of malignancy: mural nodule, tumor size (30 mm), and dilated duct size (12 mm).     

Robotic tumor-specific mesorectal excison of rectal cancer: short-term outcome of a pilot randomized trial

Background  Laparoscopic colorectal resection has become popular. The recently developed da Vinci Surgical System promises to facilitate endoscopic surgery and overcome its disadvantages. This study therefore aimed to compare the short-term results between robotic tumor-specific mesorectal excision (R-TSME) using the da Vinci Surgical System and conventional laparoscopic tumor-specific mesorectal excision (L-TSME) in rectal cancer patients. Methods  Between April 2006 and February 2007, 36 patients were randomly assigned to receive R-TSME or L-TSME. During the study, 18 patients underwent robotic low anterior resection using the da Vinci Surgical System, and 18 patients had conventional laparoscopic low anterior resection. Patient characteristics, perioperative clinical results, complications, and pathologic details were compared between the two groups. Results  The patient characteristics were not significantly different between the two groups. The mean operating time, hemoglobin change, and conversion rate were not significantly different between the groups. Complications were treated conservatively and did not require surgical intervention in the R-TSME group. The average length of stay was 6.9 ± 1.3 days in the R-TSME group and 8.7 ± 1.3 days in the L-TSME group (p < 0.001). The specimen quality of the R-TSME group was acceptable. Conclusion  Tumor-specific mesorectal excision was performed safely and effectively using the da Vinci Surgical System and the perioperative outcomes were acceptable.     

Treatment Guidelines for Branch Duct Type Intraductal Papillary Mucinous Neoplasms of the Pancreas: When Can We Operate or Observe?

Background The objectives of this study were to investigate the clinicopathological features of branch intraductal papillary mucinous neoplasm (IPMN) and to determine safe criteria for its observation. Most clinicians agree that surgical resection is required to treat main duct-type IPMN because of its high malignancy rate. However, no definite treatment guideline (with respect to surgery or observation) has been issued on the management of branch duct type IPMN. Methods We retrospectively reviewed the clinicopathological data of 138 patients who underwent operations for IPMN between 1993 and 2006 at five institutes in Korea. Results Of 138 patients (mean age, 60.6 years; 87 men, 51 women), 76 underwent pancreatoduodenectomy, 39 distal pancreatectomy, 4 total pancreatectomy, and 20 limited pancreatic resection. There were 112 benign cases: 47 adenoma, 63 borderline cases, and 26 malignant cases, with 9 of these being noninvasive and 17 invasive. By univariate analysis, tumor size and the presence of a mural nodule were identified as meaningful predictors of malignancy. By receiver operating characteristic curve analysis, a tumor size of >2 cm was found to be the most valuable predictor of malignancy. When cases were classified according to tumor size and the presence of a mural nodule, the malignancy rate for a tumor ≤2 cm without a mural nodule was 9.2%, for a tumor of ≤2 cm plus a mural nodule was 25%, and for other conditions such as tumor >2 cm, >25%. Conclusions Many branch duct IPMNs are malignant. Surgical treatment is recommended, except in cases that are strongly suspected to be benign or cases that present a high operative risk. Observation is only recommended in patients with a tumor size of ≤2 cm without a mural nodule.     

Robotic total mesorectal excision for the treatment of rectal cancer

Robotic techniques have been developed to facilitate endoscopic surgery and to overcome its disadvantages. Thus, we performed robotic total mesorectal excison (TME) in a patient with rectal cancer, using the da Vinci^® Surgical System. To our knowledge, this is the first robotic low anterior resection, based on standard TME principles, with pelvic autonomic nerve preservation. In conclusion, this robotic system is an excellent instrument for performing the standard TME procedure in rectal cancer patients.     

Robotic versus laparoscopic coloanal anastomosis with or without intersphincteric resection for rectal cancer

Robotic surgery is increasingly used in the field of rectal cancer surgery. This study aimed to compare the short- and long-term outcomes between robotic and laparoscopic ultralow anterior resection (uLAR) and coloanal anastomosis (CAA). Between January 2007 and December 2010, a retrospective chart review was performed for all patients with low rectal cancer who underwent curative uLAR and CAA with or without intersphincteric resection using either a robotic or a laparoscopic approach. The study excluded patients with tumors invading the levator ani or external sphincter, patients with T4 cancers invading the prostate or vagina, and patients for whom an open approach was used. Patients’ short- and long-term outcomes were evaluated. This study enrolled 84 consecutive patients (47 in the robotic group and 37 in the laparoscopic group). The patient characteristics and operative data did not differ significantly between the groups except for the rate of conversion to open surgery (robot, 2.1 % vs laparoscopy, 16.2 %; p = 0.02). The postoperative outcomes also were similar in the two groups, but the hospital stay was shorter in the robotic group than in the laparoscopic group (robot, 9 days vs laparoscopy, 11 days; p = 0.011). No postoperative mortality occurred. The median follow-up period was 31.5 months. No difference was shown in local recurrence, 3-year overall survival, or disease-free survival between the two groups. Robotic uLAR and CAA with or without ISR is a safe and feasible surgical approach with a lower conversion rate, a shorter hospital stay, and similar oncologic outcomes compared with a laparoscopic approach. Further prospective and case–control cohort studies with longer follow-up periods are required.     

Multidimensional Biomarker Analysis Including Mitochondrial Stress Indicators for Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is accompanied by a complex and multifactorial pathogenesis with sequential progressions from inflammation to fibrosis and then to cancer. This heterogeneity interferes with the development of precise diagnostic and prognostic strategies for NAFLD. The current approach for the diagnosis of simple steatosis, steatohepatitis, and cirrhosis mainly consists of ultrasonography, magnetic resonance imaging, elastography, and various serological analyses. However, individual dry and wet biomarkers have limitations demanding an integrative approach for the assessment of disease progression. Here, we review diagnostic strategies for simple steatosis, steatohepatitis and hepatic fibrosis, followed by potential biomarkers associated with fat accumulation and mitochondrial stress. For mitochondrial stress indicators, we focused on fibroblast growth factor 21 (FGF21), growth differentiation factor 15 (GDF15), angiopoietin-related growth factor and mitochondrial-derived peptides. Each biomarker may not strongly indicate the severity of steatosis or steatohepatitis. Instead, multidimensional analysis of different groups of biomarkers based on pathogenic mechanisms may provide decisive diagnostic/prognostic information to develop a therapeutic plan for patients with NAFLD. For this purpose, mitochondrial stress indicators, such as FGF21 or GDF15, could be an important component in the multiplexed and contextual interpretation of NAFLD. Further validation of the integrative evaluation of mitochondrial stress indicators combined with other biomarkers is needed in the diagnosis/prognosis of NAFLD.     

Colon Ischemia Associated with Buerger's Disease: Case Report and Review of the Literature

Buerger''s disease, or thromboangiitis obliterans, is a nonatherosclerotic inflammatory disease affecting the small- and medium-sized arteries and veins of the extremities (arms, hands, legs, and feet). It is most common in the Orient, Southeast Asia, India, and the Middle East, and usually affects men aged between 20 and 40 years, although it is becoming more common in women. It is well established that most such patients smoke heavily and experience an improvement in symptoms following smoking cessation. Mesenteric involvement in Buerger''s disease is extremely rare; however, we describe herein two cases of colon ischemia in patients who were previously diagnosed with lower-extremity Buerger''s disease. In one case, the patient developed colonic obstruction, and surgical resection was performed. Histopathologic findings were compatible with the chronic stage of Buerger''s disease. In the other case, angiography revealed abrupt occlusion of the inferior mesenteric artery with numerous collateral vessels, just like the corkscrew appearance found in the extremities. If patients with established Buerger''s disease of the extremities complain of gastrointestinal symptoms, early interventional diagnosis should be performed to prevent intestinal obstruction and gangrene.