Evaluation of bacterial contamination and medium-term oncological outcomes of intracorporeal anastomosis for colon cancer:A propensity score matching analysis

BACKGROUND Although intracorporeal anastomosis(IA)for colon cancer requires longer operative time than extracorporeal anastomosis(EA),its short-term postoperative results,such as early recovery of bowel movement,have been reported to be equal or better.As IA requires opening the intestinal tract in the abdominal cavity under pneumoperitoneum,there are concerns about intraperitoneal bacterial infection and recurrence of peritoneal dissemination due to the spread of bacteria and tumor cells.However,intraperitoneal bacterial contamination and medium-term oncological outcomes have not been clarified.abdominal cavity in IA.METHODS Of 127 patients who underwent laparoscopic colon resection for colon cancer from April 2015 to December 2020,75 underwent EA(EA group),and 52 underwent IA(IA group).After propensity score matching,the primary endpoint was 3-year disease-free survival rates,and secondary endpoints were 3-year overall survival rates,type of recurrence,surgical site infection(SSI)incidence,number of days on antibiotics,and postoperative biological responses.RESULTS Three-year disease-free survival rates did not significantly differ between the IA and EA groups(87.2%and 82.7%,respectively,P=0.4473).The 3-year overall survival rates also did not significantly differ between the IA and EA groups(94.7%and 94.7%,respectively;P=0.9891).There was no difference in the type of recurrence between the two groups.In addition,there were no significant differences in SSI incidence or the number of days on antibiotics;however,postoperative biological responses,such as the white blood cell count(10200 vs 8650/mm^(3),P=0.0068),C-reactive protein(6.8 vs 4.5 mg/dL,P=0.0011),and body temperature(37.7 vs 37.5℃,P=0.0079),were significantly higher in the IA group.CONCLUSION IA is an anastomotic technique that should be widely performed because its risk of intraperitoneal bacterial contamination and medium-term oncological outcomes are comparable to those of EA.

Establishment of a surveillance program for anal cancer in Crohn's disease

This letter discusses the incidence of anal cancer among Crohn's disease(CD)-related malignancies.Patients with CD have been demonstrated to be at a higher risk of developing small bowel and colorectal cancers than healthy individuals.Although CD-associated anal cancer is relatively rare,patients with CD accom-panied by anal or perianal lesions are at increased risk of anal cancer.Addi-tionally,compared to ulcerative colitis,which is also an inflammatory disease,CD-related anal cancer is often detected at an advanced stage owing to the complexity of CD and is associated with a poor prognosis with frequent local recurrences.Therefore,the detection of early-stage cancer is crucial for improving the prognosis.However,the surveillance methods recommended for CD-related malignancies in the United States and Europe are similar to those for ulcerative colitis.They are not appropriate for detecting CD-related malignancies in the recto-anal region.Therefore,there is an urgent need for surveillance programs aimed at the early detection of malignant anorectal lesions in patients with CD.

Machine learning algorithms able to predict the prognosis of gastric cancer patients treated with immune checkpoint inhibitors

BACKGROUND Although immune checkpoint inhibitors(ICIs)have demonstrated significant survival benefits in some patients diagnosed with gastric cancer(GC),existing prognostic markers are not universally applicable to all patients with advanced GC.AIM To investigate biomarkers that predict prognosis in GC patients treated with ICIs and develop accurate predictive models.METHODS Data from 273 patients diagnosed with GC and distant metastasis,who un-derwent≥1 cycle(s)of ICIs therapy were included in this study.Patients were randomly divided into training and test sets at a ratio of 7:3.Training set data were used to develop the machine learning models,and the test set was used to validate their predictive ability.Shapley additive explanations were used to provide insights into the best model.RESULTS Among the 273 patients with GC treated with ICIs in this study,112 died within 1 year,and 129 progressed within the same timeframe.Five features related to overall survival and 4 related to progression-free survival were identified and used to construct eXtreme Gradient Boosting(XGBoost),logistic regression,and decision tree.After comprehensive evaluation,XGBoost demonstrated good accuracy in predicting overall survival and progression-free survival.CONCLUSION The XGBoost model aided in identifying patients with GC who were more likely to benefit from ICIs therapy.Patient nutritional status may,to some extent,reflect prognosis.

Goblet cell carcinoid of the appendix:Six case reports

BACKGROUND Goblet cell carcinoid(GCC)of the appendix is a rare tumor characterized by neuroendocrine and adenocarcinoma features.Accurate preoperative diagnosis is very difficult,with most patients complaining mainly of abdominal pain.Computed tomography shows swelling of the appendix,so diagnosis is usually made incidentally after appendectomy based on a preoperative diagnosis of appendicitis.Even if a patient undergoes preoperative colonoscopy,accurate endoscopic diagnosis is very difficult because GCC shows a submucosal growth pattern with invasion of the appendiceal wall.CASE SUMMARY Between 2017 and 2022,6 patients with GCC were treated in our hospital.The presenting complaint for 5 of these 6 patients was abdominal pain.All 5 patients underwent appendectomy,including 4 for a preoperative diagnosis of appendicitis and the other for diagnosis and treatment of an appendiceal tumor.The sixth patient presented with vomiting and underwent ileocecal resection for GCC diagnosed from preoperative biopsy.Although 2 patients with GCC underwent colonoscopy,no neoplastic changes were identified.Two of the six patients showed lymph node metastasis on pathological examination.As of the last followup(median:15 mo),all cases remained alive without recurrence.CONCLUSION As preoperative diagnosis of GCC is difficult,this possibility must be considered during surgical treatments for presumptive appendicitis.

Distal margin distance in radical resection of locally advanced rectal cancer after neoadjuvant therapy

Colorectal cancer has a high incidence and mortality rate in China, with the majority of cases being middle and low rectal cancer. Surgical intervention is currently the main treatment modality for locally advanced rectal cancer, with the common goal of improving oncological outcomes while preserving function. The controversy regarding the circumferential resection margin distance in rectal cancer surgery has been resolved. With the promotion of neoadjuvant therapy concepts and advancements in technology, treatment strategies have become more diverse.Following tumor downstaging, there is an increasing trend towards extending the safe distance of distal rectal margin. This provides more opportunities for patients with low rectal cancer to preserve their anal function.However, there is currently no consensus on the specific distance of distal resection margin.

Role of 18F-fluorodeoxyglucose positron emission tomography imaging in surgery for pancreatic cancer

AIM： To evaluate the role of positron emission tomography using 18F-fluorodeoxyglucose （FDG-PET） in the surgical management of patients with pancreatic cancer, including the diagnosis, staging, and selection of patients for the subsequent surgical treatment. METHODS： This study involved 53 patients with proven primary pancreatic cancer. The sensitivity of diagnosing the primary cancer was examined for FDG-PET CT, cytological examination of the bile or pancreatic juice, and the serum levels of carcinoembrionic antigens （CEA） and carbohydrate antigen 19-9 （CA29-9）. Next, the accuracy of staging was compared between FDG-PET and CT. Finally, FDG-PET was analyzed semiquantitatively using the standard uptake value （SUV）. The impact of the SUV on patient management was evaluated by examining the correlations between the SUV and the histological findings of cancer. RESULTS： The sensitivity of FDG-PET, CT, cytological examination of the bile or pancreatic juice, and the serum levels of CEA and CA19-9 were 92.5%, 88.7%, 46.4%, 37.7% and 69.8%, respectively. In staging, FDG-PET was superior to CT only in diagnosing distant disease （bone metastasis）. For local staging, the sensitivity of CT was better than that of FDG-PEr. The SUV did not correlate with the pTNM stage, grades, invasions to the vessels and nerve, or with the size of the tumor. However, there was a statistically significant difference （4.6 ± 2.9 vs 7.8 ± 4.5, P = 0.024） in the SUV between patients with respectable and unresectable disease. CONCLUSION： FDG-PET is thus considered to be useful in the diagnosis of pancreatic cancer. However, regarding the staging of the disease, FDG-PET is not considered to be a sufficiently accurate diagnostic modality. Although the SUV does not correlate with the patho-histological prognostic factors, it may be useful in selecting patients who should undergo subsequent surgical treatment.

Current status of function-preserving surgery for gastric cancer

Recent advances in diagnostic techniques have allowed the diagnosis of gastric cancer(GC)at an early stage.Due to the low incidence of lymph node metastasis and favorable prognosis in early GC,function-preserving surgery which improves postoperative quality of life may be possible.Pylorus-preserving gastrectomy(PPG)is one such function-preserving procedure,which is expected to offer advantages with regards to dumping syndrome,bile reflux gastritis,and the frequency of flatus,although PPG may induce delayed gastric emptying.Proximal gastrectomy(PG)is another functionpreserving procedure,which is thought to be advantageous in terms of decreased duodenogastric reflux and good food reservoir function in the remnant stomach,although the incidence of heartburn or gastric fullness associated with this procedure is high.However,these disadvantages may be overcome by the reconstruction method used.The other important problem after PG is remnant GC,which was reported to occur in approximately 5%of patients.Therefore,the reconstruction technique used with PG should facilitate postoperativeendoscopic examinations for early detection and treatment of remnant gastric carcinoma.Oncologic safety seems to be assured in both procedures,if the preoperative diagnosis is accurate.Patient selection should be carefully considered.Although many retrospective studies have demonstrated the utility of function-preserving surgery,no consensus on whether to adopt functionpreserving surgery as the standard of care has been reached.Further prospective randomized controlled trials are necessary to evaluate survival and postoperative quality of life associated with function-preserving surgery.

Technical feasibility of laparoscopic extended surgerybeyond total mesorectal excision for primary or recurrentrectal cancer

Relatively little is known about the oncologic safety of laparoscopic surgery for advanced rectal cancer.Recently, large randomized clinical trials showed that laparoscopic surgery was not inferior to open surgery, as evidenced by survival and local control rates. However, patients with T4 tumors were excluded from these trials. Technological advances in the instrumentation and techniques used by laparoscopic surgery have increased the use of laparoscopic surgery for advanced rectal cancer. High-definition, illuminated, and magnified images obtained by laparoscopy may enable more precise laparoscopic surgery than open techniques, even during extended surgery for T4 or locally recurrent rectal cancer. To date, the quality of evidence regarding the usefulness of laparoscopy for extended surgery beyond total mesorectal excision has been low because most studies have been uncontrolled series, with small sample sizes, and long-term data are lacking. Nevertheless, laparoscopic extended surgery for rectal cancer, when performed by specialized laparoscopic colorectal surgeons, has been reported safe in selected patients, with significant advantages, including a clear visual field and less blood loss. This review summarizes current knowledge on laparoscopic extended surgery beyond total mesorectal excision for primary or locally recurrent rectal cancer.

Reduction effect of bacterial counts by preoperative saline lavage of the stomach in performing laparoscopic and endoscopic cooperative surgery

AIM: To investigate the effects of gastric lavage with 2000 mL of saline in laparoscopic and endoscopic cooperative surgery.

Superiority of laparoscopic rectal surgery:Towards a new era

While laparoscopic colon surgery has been established to some degree over this decade,laparoscopic rectal surgery is not standard yet because of the difficulty of making a clear surgical field,the lack of precise anatomy of the pelvis,immature procedures of rectal transaction and so on.On the other hand,maintaining a clear surgical field via the magnified laparoscopy may allow easier mobilization of the rectum as far as the levetor muscle level and may result less blood loss and less invasiveness.However,some unique techniques to keep a clear surgical field and knowledge about anatomy of the pelvis are required to achieve the above superior operative outcomes.This review article discusses how to keep a clear operative field,removing normally existing abdominal structures,and how to transact the rectum and restore the discontinuity based on anatomical investigations.According to this review,laparoscopic rectal surgery will become a powerful modality to accomplish a more precise procedure which has been technically impossible so far,actually entering a new era.

Significance of regenerating islet-derived type Ⅳ gene expression in gastroenterological cancers

The regenerating islet-derived members （Reg）, a group of small secretory proteins, which are involved in cell proliferation or differentiation in digestive organs, are upregulated in several gastrointestinal cancers, functioning as trophic or antiapoptotic factors. Regenerat- ing islet-derived type Ⅳ （RegⅣ）, a member of the Reg gene family, has been reported to be overexpressed in gastroenterological cancers. RegIV overexpression in tumor cells has been associated with carcinogen- esis, cell growth, survival and resistance to apoptosis. Cancer tissue expressing RegIV is generally associated with more malignant characteristics than that with- out such expression, and RegⅣ is considered a novel prognostic factor as well as diagnostic marker in some gastroenterological cancers. We previously investigated the expression levels of RegⅣ mRNA of 202 surgical colorectal cancer specimens with quantitative real-time reverse-transcriptase polymerase chain reaction and reported that a higher level of RegⅣ gene expression was a significant independent predictor of colorec- tal cancer. The biologic functions of RegⅣ protein in cancer tissue, associated with carcinogenesis, anti- apoptosis and invasiveness, are being elucidated by molecular investigations using transfection techniques or neutralizing antibodies of RegIV, and the feasibility of antibody therapy targeting RegIV is being assessed. These studies may lead to novel therapeutic strate- gies for gastroenterological cancers expressing RegⅣ. This review article summarizes the current information related to biological functions as well as clinical impor- tance of RegⅣ gene to clarify the significance of Reg~ expression in gastroenterological cancers.

Prognostic factors of minimally invasive surgery for gastric cancer: Does robotic gastrectomy bring oncological benefit?

BACKGROUND Gastric cancer is the third leading cause of cancer-related death worldwide and surgical resection remains the sole curative treatment for gastric cancer.Minimally invasive gastrectomy including laparoscopic and robotic approaches has been increasingly used in a few decades.Thus far,only a few reports have investigated the oncological outcomes following minimally invasive gastrectomy.AIM To determine the 5-year survival following minimally invasive gastrectomy for gastric cancer and identify prognostic predictors.METHODS This retrospective cohort study identified 939 patients who underwent gastrectomy for gastric cancer during the study period.After excluding 125 patients with non-curative surgery(n=77),other synchronous cancer(n=2),remnant gastric cancer(n=25),insufficient physical function(n=13),and open gastrectomy(n=8),a total of 814 consecutive patients with primary gastric cancer who underwent minimally invasive R0 gastrectomy at our institution between 2009 and 2014 were retrospectively examined.Accordingly,5-year overall and recurrence-free survival were analyzed using the Kaplan–Meier method with the log-rank test and Cox regression analyses,while factors associated with survival were determined using multivariate analysis.RESULTS Our analysis showed that age>65 years,American Society of Anesthesiologists(ASA)physical status 3,total or proximal gastrectomy,and pathological T4 and N positive status were independent predictors of both 5-year overall and recurrencefree survival.Accordingly,the included patients had a 5-year overall and recurrence-free survival of 80.3%and 78.2%,respectively.Among the 814 patients,157(19.3%)underwent robotic gastrectomy,while 308(37.2%)were diagnosed with pathological stage II or III disease.Notably,our findings showed that robotic gastrectomy was an independent positive predictor for recurrence-free survival in patients with pathological stage II/III[hazard ratio:0.56(0.33-0.96),P=0.035].Comparison of recurrence-free survival between the robotic and laparoscopic approach using propensity score matching analysis verified that the robotic group had less morbidity(P=0.005).CONCLUSION Age,ASA status,gastrectomy type,and pathological T and N status were prognostic factors of minimally invasive gastrectomy,with the robot approach possibly improving long-term outcomes of advanced gastric cancer.

Plasma MMP-2 and MMP-7 levels are elevated first month after surgery and may promote growth of residual metastases

BACKGROUND MMP-2 also known as gelatinase A and MMP-7(matrilysin)are members of the zinc-dependent family of MMPs(Matrix metalloproteinase).MMP-2 and MMP-7 are remodeling enzymes that digest extracellular matrix;MMP-2 is extensively expressed during development and is upregulated at sites of tissue damage,inflammation,and in stromal cells of metastatic tumors.MMP-7 is expressed in the epithelial cells and in a variety of cancers including colon tumors.Plasma MMP-2 and MMP-7 levels were assessed before and after minimally invasive colorectal resection for cancer pathology.AIM To determine plasma MMP-2 and MMP-7 levels before and after minimally invasive colorectal resection for cancer pathology.METHODS Patients enrolled in a plasma bank for whom plasma was available were eligible.Plasma obtained from preoperative(Preop)and postoperative blood samples was used.Only colorectal cancer(CRC)patients who underwent elective minimally invasive cancer resection with preop,post-operative day(POD)1,3 and at least 1 late postop sample(POD 7-34)were included.Late samples were bundled into 7 d blocks(POD 7-13,14-20,etc.)and treated as single time points.Plasma MMP-2 and MMP-7 levels were determined via enzyme-linked immunosorbent assay in duplicate.RESULTS Total 88 minimally invasive CRC resection CRC patients were studied(right colectomy,37%;sigmoid,24%;and LAR/AR 18%).Cancer stages were:1,31%;2,30%;3,34%;and 4,5%.Mean Preop MMP-2 plasma level(ng/mL)was 179.3±40.9(n=88).Elevated mean levels were noted on POD1(214.3±51.2,n=87,P<0.001),POD3(258.0±63.9,n=80,P<0.001),POD7-13(229.9±62.3,n=65,P<0.001),POD 14-20(234.9±47.5,n=25,P<0.001),POD 21-27(237.0±63.5,n=17,P<0.001,)and POD 28-34(255.4±59.7,n=15,P<0.001).Mean Preop MMP-7 level was 3.9±1.9(n=88).No significant differences were noted on POD 1 or 3,however,significantly elevated levels were noted on POD 7-13(5.7±2.5,n=65,P<0.001),POD 14-20(5.9±2.5,n=25,P<0.001),POD 21-27(6.1±3.6,n=17,P=0.002)and on POD 28-34(6.8±3.3,n=15 P<0.001,)vs preop levels.CONCLUSION MMP-2 levels are elevated for 5 wk and MMP-7 levels elevated for weeks 2-6.The etiology of these changes in unclear,trauma and wound healing likely play a role.These changes may promote residual tumor growth and metastasis.

Changing trends of clinicopathologic features and survival duration after surgery for gastric cancer in Northeast China

BACKGROUND Through analyzing the data from a single institution in Northeast China,this study revealed the possible clinicopathologic characteristics that influence the prognosis of patients with gastric cancer(GC).AIM To evaluate the changing trends of clinicopathologic features and survival duration after surgery in patients with GC in Northeast China,which is a highprevalence area of GC.METHODS The study analyzed the difference in clinicopathologic features and survival duration after surgery of 5887 patients who were histologically diagnosed with GC at the Harbin Medical University Cancer Hospital.The study mainly analyzed the data in three periods,2000 to 2004(Phase 1),2005 to 2009(Phase 2),and 2010 to 2014(Phase 3).RESULTS Over time,the postoperative survival rate significantly increased from 2000 to 2014.In the past 15 years,compared with Phases 1 and 2,the tumor size was smaller in Phase 3(P<0.001),but the proportion of high-medium differentiated tumors increased(P<0.001).The proportion of early GC gradually increased from 3.9%to 14.4%(P<0.001).A surprising improvement was observed in the mean number of retrieved lymph nodes,ranging from 11.4 to 27.5(P<0.001).The overall 5-year survival rate increased from 24%in Phase 1 to 43.8%in Phase 3.Through multivariate analysis,it was found that age,tumor size,histologic type,tumor-node-metastasis stage,depth of invasion,lymph node metastasis,surgical approach,local infiltration,radical extent,number of retrieved lymph nodes,and age group were independent risk factors that influenced the prognosis of patients with GC.CONCLUSION The clinical features of GC in Northeast China changed during the observation period.The increasing detection of early GC and more standardized surgical treatment effectively prolonged lifetimes.

Current status and future perspectives for the treatment of resectable locally advanced esophagogastric junction cancer:A narrative review

Incidence rates for esophagogastric junction cancer are rising rapidly worldwide possibly due to the economic development and demographic changes.Therefore,increased attention has been paid to the prevention,diagnosis,and the treatment of esophagogastric junction cancer.Although there are discrepancies in the treatment strategy between Asian and Western countries,surgery remains the mainstay of treatment for esophagogastric junction cancer.Recent developments of perioperative multidisciplinary treatment may lead to better therapeutic effect,higher complete resection rate,and better control of the residual diseases,thus result in prolonged prognosis.In this review,we will focus on the treatment of locally advanced resectable esophagogastric junction cancer,and discuss the current status and future perspectives of the perioperative treatment including chemotherapy,radiation therapy,and immunotherapy,as well as the surgical strategy.Better understanding of the latest treatment strategy and future overlook may enable to standardize and individualize the treatment for esophagogastric junction cancer,thus leading to better prognosis for those patients.

Oncologic impact of colonic stents for obstructive left-sided colon cancer

Colonic stenting has had a significant positive impact on the management of obstructive left-sided colon cancer(OLCC) in terms of both palliative treatment and bridge-to-surgery(BTS). Notably, many studies have convincingly demonstrated the effectiveness of stenting as a BTS, resulting in improvements in shortterm outcomes and quality of life, safety, and efficacy in subsequent curative surgery, and increased cost-effectiveness, whereas the safety of chemotherapy after stenting and the long-term outcomes of stenting as a BTS are controversial. Several studies have suggested an increased risk of perforation in patients receiving bevacizumab chemotherapy after colonic stenting. In addition, several pathological analyses have suggested a negative oncological impact of colonic stenting. In contrast, many recent studies have demonstrated that colonic stenting for OLCC does not negatively impact the safety of chemotherapy or long-term oncological outcomes. The updated version of the European Society of Gastrointestinal Endoscopy guidelines released in 2020 included colonic stenting as a BTS for OLCC as a recommended treatment. It should be noted that the experience of endoscopists is involved in determining technical and clinical success rates and possibly oncological outcomes. This review discusses the positive and negative impacts of colonic stenting on OLCC treatment, particularly in terms of oncology.

Surgery for pancreatic tumors in the midst of COVID-19 pandemic

The spread of the new coronavirus(COVID-19)infection in 2020 has had a significant impact on the treatment of cancer worldwide.During the COVID-19 pandemic,the biggest challenge for pancreatic surgeons is the difficulty in providing oncological care.In this review article,from the standpoint of surgeons,we explain the concept of triaging of patients with pancreatic tumors under the COVID-19 pandemic,and the actual impact of COVID-19 on the treatment of patients with pancreatic tumors.The most vital points in selecting the best therapeutic approach for patients with pancreatic tumors during this pandemic are(1)Oncologists need to tailor the treatment plan based on the COVID-19 phase,tumor malignant potential,and patients’comorbidities;and(2)Optimal treatment for pancreatic cancer should be planned according to the condition of each patient and tumor resectability based on national comprehensive cancer network resectability criteria.To choose the best therapeutic approach for patients with pancreatic tumors during this pandemic,we need to tailor the treatment plan based on elective surgery acuity scale(ESAS).Newly established ESAS for pancreatic tumor and flowchart indicating the treatment strategy of pancreatic cancer,are feasible to overcome this situation.

Optimal resection of gastric bronchogenic cysts based on anatomical continuity with adherent gastric muscular layer: A case report

BACKGROUND Bronchogenic cysts are congenital lesions requiring radical resection because of malignant potential.However,a method for the optimal resection of these cysts has not been completely elucidated.CASE SUMMARY Herein,we presented three patients with bronchogenic cysts that were located adjacent to the gastric wall and resected laparoscopically.The cysts were detected incidentally with no symptoms and the preoperative diagnosis was challenging to obtain via radiological examinations.Based on laparoscopic findings,the cyst was attached firmly to the gastric wall and the boundary between the gastric and cyst walls was difficult to identify.Consequently,resection of cysts alone caused cystic wall injury in Patient 1.Meanwhile,the cyst was resected completely along with a part of the gastric wall in Patient 2.Histopathological examination revealed the final diagnosis of bronchogenic cyst and revealed that the cyst wall shared the muscular layer with the gastric wall in Patients 1 and 2.In Patient 3,the cyst was located adjacent to the gastric wall but histopathologically originated from diaphragm rather than stomach.All the patients were free from recurrence.CONCLUSION The findings of this study state that a safe and complete resection of bronchogenic cysts required the adherent gastric muscular layer or full-thickness dissection,if bronchogenic cysts are suspected via pre-and/or intraoperative findings.

Tissue pad degradation of ultrasonic device may enhance thermal injury and impair its sealing performance in liver surgery

BACKGROUND Ultrasonic devices are widely used in many surgical fields,including hepatectomy;however,the negative effects of tissue pad degradation of ultrasonic devices,including those in liver surgery,remain unknown.The Harmonic®1100(H-1100)scalpel has advanced heat control technology than previous models,such as the Harmonic®HD1000i(H-HD1000i).We hypothesized that,because of its advanced temperature-control technology,the H-1100 scalpel would show less tissue pad degradation,resulting in superior sealing performance,compared to that with the H-HD1000i scalpel.AIM To elucidate ultrasonic device tissue pad degradation effects on instrument temperature and sealing performance using ex vivo porcine liver/vessel models.METHODS Two different harmonic scalpels were used and compared:A newer model,the H-1100 scalpel,and an older model,the H-HD1000i scalpel.Using ex vivo porcine livers,each instrument was activated until the liver parenchyma was dissected.The device temperature(passive jaw temperature)was measured after every 10 consecutive activations,until 300 transections of the porcine liver were performed.Tissue pad degradation was evaluated after 300 activations.Sealing performance was evaluated using excised porcine carotid vessels;vessel sealing speed and frequency of vessel burst pressure below 700 mmHg were determined after 300 transections of porcine liver parenchyma.RESULTS The temperature of the H-HD1000i scalpel was approximately 10℃higher than that of the H-1100 scalpel,and gradually increased as the number of activations increased.The median passive jaw temperature of the H-HD1000i scalpel was significantly higher than that of the H-1100 scalpel(73.4℃vs 65.1℃;P<0.001).After 300 transections of porcine liver parenchyma,less tissue pad degradation was observed with the H-1100 scalpel than with the H-HD1000i scalpel(0.08 mm vs 0.51 mm).The H-1100 scalpel demonstrated faster vessel-sealing speed(4.9 sec.vs 5.1 sec.)and less frequent vessel burst pressure<700 mmHg(0%vs 40%)after 300 activations than the H-HD1000i scalpel;however,the difference did not reach statistical significance(P=0.21 and P=0.09,respectively).CONCLUSION In an ex vivo porcine hepatectomy model,the H-1100 scalpel shows lower passive jaw temperature and maintains its sealing performance by avoiding tissue pad degradation compared to that with the H-HD1000i.

Perforation of the duodenum during the retrograde cholangiopancreatography treated without surgery

Perforation after endoscopic retrograde cholan- giopancreatography (ERCP) is a rare but severe complication. Management of ERCP-associated duodenal perforation remains controversial. Some recommend surgery, while others recommend conservative treatment. We describe the case who developed perforation of the duodenum and gas in the retroperitoneal cavity after ERCP. There was no sign of peritonitis, pancreatitis or sepsis. The patient was treated by conservative therapy without operation, and finally, fully re- covered from perforation.