Laparoscopic versus open colectomy for locally advanced colon cancer in obese patients: a nationwide, multicenter, propensity score-based analysis of short- and long-term outcomes.

OBJECTIVE: This study evaluated the short-and long-term outcomes of laparoscopic colectomy versus open surgery in obese patients (body mass index ≥25 kg/m2) with locally advanced colon cancer to ascertain the non-inferiority of laparoscopic surgery to open surgery. METHODS: In this large cohort study (UMIN-ID: UMIN000033529), we retrospectively reviewed prospectively collected data from consecutive patients who underwent laparoscopic or open surgery for pathological stage II-III colon cancer between 2009 and 2013. A comparative analysis was performed after propensity score matching between the laparoscopic and open surgery groups. The primary endpoint was the 3-year relapse-free survival (RFS). RESULTS: We identified 1575 eligible patients from 46 institutions. Each group comprised 526 propensity score-matched patients. Comparing the laparoscopic versus open surgery group, laparoscopic surgery was significantly associated with increased median operating time (225 vs. 192.5 min; P < .0001) and decreased median estimated blood loss (20 vs. 140 ml; P < .0001). Lymph node retrieval (20 vs. 19; P = 0.4392) and postoperative complications (4.6% vs. 5.7%; P = 0.4851) were similar, postoperative hospital stay was shorter (10 vs. 12 days; P < .0001), and the 3-year RFS rates were similar (82.8 vs. 81.2%). The hazard ratio (HR) for relapse-free survival for laparoscopic versus open surgery was 0.927 (90% confidence interval [CI], 0.747-1.150, one-sided P for non-inferiority = .001), indicating that for obese patients with colon cancer, laparoscopic surgery was non-inferior to open surgery. CONCLUSION: Laparoscopic surgery in obese patients with colon cancer offers advantages in terms of short-term outcomes and no disadvantages in terms of long-term outcomes.

Update on endoscopic surgery in Japan: Results of the 16th National Survey of endoscopic surgery by the Japan Society for Endoscopic Surgery.

This article reports the results of the 16th National Survey conducted by the Japan Society for Endoscopic Surgery (JSES) for 2020 and 2021. Laparoscopic cholecystectomy was first introduced to Japan in 1990 and has rapidly become popular because of its minimally invasive nature. Since then, the number of objective organs and indications for laparoscopic surgery have gradually expanded. In 2021, 290 787 patients underwent endoscopic surgery in all surgical domains. Of these, 124 614, 110 757, 23 156, 21 771, 6543, 2614, 535, 465, 247, and 58 underwent abdominal, obstetric and gynecologic, thoracic, urological, pediatric, orthopedic, bariatric, mammary and thyroid gland, cardiovascular, and plastic surgery, respectively. Owing to the impact of the coronavirus disease 2019 (COVID-19) infection spread, the incidence of many surgeries decreased in 2020, and levels are only now gradually recovering. However, despite the impact of COVID-19, robot-assisted surgeries were increasingly applied. The rate of complications did not change significantly, indicating that the procedure was performed safely, even with the spread of COVID-19.

Artificial intelligence for surgical safety during laparoscopic gastrectomy for gastric cancer: Indication of anatomical landmarks related to postoperative pancreatic fistula using deep learning.

BACKGROUND: Postoperative pancreatic fistula (POPF) is a critical complication of laparoscopic gastrectomy (LG). However, there are no widely recognized anatomical landmarks to prevent POPF during LG. This study aimed to identify anatomical landmarks related to POPF occurrence during LG for gastric cancer and to develop an artificial intelligence (AI) navigation system for indicating these landmarks. METHODS: Dimpling lines (DLs)-depressions formed between the pancreas and surrounding organs-were defined as anatomical landmarks related to POPF. The DLs for the mesogastrium, intestine, and transverse mesocolon were named DMP, DIP, and DTP, respectively. We included 50 LG cases to develop the AI system (45/50 were used for training and 5/50 for adjusting the hyperparameters of the employed system). Regarding the validation of the AI system, DLs were assessed by an external evaluation committee using a Likert scale, and the pancreas was assessed using the Dice coefficient, with 10 prospectively registered cases. RESULTS: Six expert surgeons confirmed the efficacy of DLs as anatomical landmarks related to POPF in LG. An AI system was developed using a semantic segmentation model that indicated DLs in real-time when this system was synchronized during surgery. Additionally, the distribution of scores for DMP was significantly higher than that of the other DLs (p < 0.001), indicating the relatively high accuracy of this landmark. In addition, the Dice coefficient of the pancreas was 0.70. CONCLUSIONS: The DLs may be used as anatomical landmarks related to POPF occurrence. The developed AI navigation system can help visualize the DLs in real-time during LG.

Laparoscopic vs. open surgery for rectal cancer in patients with obesity: short-term outcomes and relapse-free survival across age groups.

PURPOSE: To investigate the efficacy of laparoscopic surgery for rectal cancer in obese and older patients, who are often characterized by a higher prevalence of comorbidities and physical decline. METHODS: This large-scale multicenter retrospective cohort study included 524 patients with a body mass index of 25 or higher who underwent either open or laparoscopic surgery for stage II or III rectal cancer between 2009 and 2013. We assessed the short-term outcomes and relapse-free survival by comparing these surgical modalities. The patients were stratified into 404 non-elderly (< 70 years) and 120 elderly (≥ 70 years) patients. RESULTS: In both patient groups, laparoscopic surgery was associated with a significantly reduced blood loss (non-elderly: 41 vs. 545 ml; elderly: 50 vs. 445 ml) and shorter hospital stays (non-elderly: 10 vs. 19 days; elderly: 15 vs. 20 days) than open surgery. The overall complications and relapse-free survival showed no significant differences between the two surgical techniques in either age group. Additionally, the impact of the laparoscopic procedure on the relapse-free survival remained consistent between the age groups. CONCLUSION: Laparoscopic surgery offers short-term benefits for patients with obesity and rectal cancer compared to open surgery, regardless of age, without influencing the long-term prognosis.

Novel reconstruction method using long and narrow gastric tube in laparoscopic proximal gastrectomy for cancer: a retrospective case series study.

Background and objectives: To clarify the safety and feasibility of laparoscopic proximal gastrectomy (LPG) with our novel reconstruction methods. Methods: Novel method is a reconstruction with a long and narrow gastric tube with widening of the proximal side created by linear stapler, and esophagogastrostomy is performed by linear stapler. In conventional method, esophagogastrostomy is performed by a circular stapler. Short- and long-term outcomes of a novel method were compared with those of conventional method. Results: A total of 44 patients whom LPG was performed were enrolled in this retrospective study. No cases of anastomotic leakage and stenosis were observed in both groups. The cases of postoperative reflux esophagitis (Grade B or higher) at 1 year after operation in the Novel group were less than those in the Conventional group (17% vs. 44%). Conclusion: LPG with novel reconstruction method can be easily performed, and may be feasible for the treatment of proximal gastric cancer.

Prediction of intraoperative surgical difficulty during laparoscopic cholecystectomy using drip infusion cholangiography with computed tomography.

BACKGROUND: Although findings from drip infusion cholangiography with computed tomography (DIC-CT) are useful in preoperative anatomic evaluation for laparoscopic cholecystectomy (LC), their relationship with intraoperative surgical difficulty based on the difficulty score (DS) proposed by Tokyo Guidelines 2018 is unclear. We examined this relationship. METHODS: Data were collected from 202 patients who underwent LC for benign gallbladder (GB) disease with preoperative DIC-CT in our department. DIC-CT findings were classified into GB-positive and GB-negative groups based on GB opacification, and clinical characteristics were compared. DS assessed only on findings from around Calot's triangle was considered "cDS", and patients were divided into cDS ≤2 and ≥3 groups. Preoperative data including DIC-CT findings were evaluated using multivariate analysis. RESULTS: DIC-CT findings showed 151 (74.8%) GB-positive and 51 (25.2%) GB-negative patients. Surgical outcomes were significantly better in the GB-positive versus GB-negative group for operation time (107 vs. 154 min, p < .001), blood loss (8 vs. 25 mL, p < .001), cDS (0.8 vs. 2.2, p < .001), and critical view of safety score (4.0 vs. 3.1, p < .001). cDS was ≤2 in 174 (86.1%) and ≥3 in 28 (13.9%) patients. By multivariate analysis, DIC-CT findings and alkaline phosphatase values were independent factors predicting intraoperative difficulty. CONCLUSION: DIC-CT findings are useful for predicting cDS in LC.

Prognostic significance of lymph node metastasis in pancreatic tail cancer: A multicenter retrospective study.

Background: Distal pancreatectomy (DP) with lymph node (LN) dissection is the standard procedure for pancreatic ductal adenocarcinoma of the tail (Pt-PDAC). However, the optimal surgery including extent of LN dissection is still being debated. The present study investigated the incidence and prognostic impact of LN metastasis on patients suffering from Pt-PDAC. Patients and method: This multicenter, retrospective study involved 163 patients who underwent DP for resectable Pt-PDAC at 12 institutions between 2013 and 2017. The frequency of LN metastasis and the effect of LN dissection on Pt-PDAC prognosis were investigated. Results: There were high incidences of metastases to the LNs along the splenic artery in the patients with Pt-PDAC (39%). The rate of metastases in the LNs along the common hepatic, left gastric, and celiac arteries were low, and the therapeutic index for these LNs was zero. In pancreatic tail cancer located more distally, there were no metastases to the LNs along the common hepatic artery. Multivariate analysis revealed that tumor size was the only independent factor related to recurrence-free survival (HR = 2.01, 95% CI = 1.33-3.05, p = 0.001). The level of pancreas division and LN dissection along the common hepatic artery did not affect the site of tumor recurrence or recurrence-free survival. Conclusions: LN dissection along the hepatic artery for Pt-PDAC has little significance. Distal pancreatic transection may be acceptable in terms of oncological safety, but further examination of short-term outcomes and preservation of pancreatic function is required.

Investigation of the impact of COVID-19 on postoperative outcomes using a nationwide Japanese database of patients undergoing laparoscopic distal gastrectomy and low anterior resection for gastric cancer and rectal cancer.

Background: The COVID-19 outbreak made conventional medical care impossible, forcing changes in both healthcare providers and patients. In Japan, COVID-19 infection began spreading in earnest in 2020 and exploded in 2021. There was concern that the medical impact of COVID-19 in 2021 would differ from that in 2020. We aimed to clarify the impact of COVID-19 on mortality and anastomotic leakage in laparoscopic surgery for gastric cancer and rectal cancer in Japan using the National Clinical Database (NCD). Methods: We collected data from patients who underwent laparoscopic distal gastrectomy (LDG) and laparoscopic low anterior resection (LLAR) from January 2018 to December 2021 from the NCD, a web-based surgical registration system in Japan. The number of surgical cases, monthly incidence of mortality and morbidity (anastomotic leakage), standardized mortality ratio (SMR), and standardized morbidity-leakage ratio (SMLR [ratio of observed patients to expected patients calculated using the risk calculator established in the NCD]) were evaluated. Results: The numbers of LDG and LLAR cases continued to decline in the first year of the pandemic in 2020 and were as low in 2021 as in 2020. Although the numbers of robot-assisted LDG and LLAR cases increased, the growth rate was lower than the rate of increase prior to the pandemic. Mortality and anastomotic leakage, two of the most important complications, as assessed by SMR and SMLR, did not worsen during the pandemic in comparison to the pre-pandemic period. Conclusions: Laparoscopic surgeries were performed safely in Japan and were not affected by the COVID-19 pandemic.

Risk factors of bleeding during rectal cancer surgery in obese patients in Japan.

BACKGROUND: According to several clinical trials for patients with rectal cancer, laparoscopic surgery significantly reduces intraoperative complications and bleeding compared with laparotomy and demonstrated comparable long-term results. However, obesity is considered one of the risk factors for increased surgical difficulty, including complication rate, prolonged operation time, and bleeding. METHODS: Patients with clinical pathological stage II/III rectal cancer and a body mass index of ≥25 kg/m2 who underwent laparotomy or laparoscopic surgery between January 2009 and December 2013 at 51 institutions participating in the Japan Society of Laparoscopic Colorectal Surgery were included. These patients were divided into major bleeding (>500 mL) group and minor bleeding (≤500 mL) group. The risk factors of major bleeding were evaluated by univariate and multivariate analyses. RESULTS: This study included 517 patients, of which 74 (19.9%) experienced major bleeding. Patient characteristics did not significantly differ between the two groups. The major bleeding group had a longer operative time (p < 0.001) and a larger tumor size than the minor bleeding group (p = 0.011). In the univariate analysis, age >65 years, laparotomy, operative time >300 min, and multivisceral resection were significantly associated with intraoperative massive bleeding. In the multivariate analysis, age >65 years (odds ratio [OR], 2.29; 95% confidence interval [CI], 1.13-4.82), laparotomy (OR, 20.82; 95% CI, 11.56-39.75), operative time >300 min (OR, 5.39; 95% CI, 1.67-132), and multivisceral resection (OR, 10.72; 95% CI, 2.47-64.0) showed to be risk factors for massive bleeding. CONCLUSION: Age >65 years, laparotomy, operative time >300 min, and multivisceral resection were risk factors for massive bleeding during rectal cancer surgery in patients with obesity.

Current status and issues regarding surgical education in the region: a questionnaire survey in Oita prefecture in Japan.

BACKGROUND: The shortage and aging of surgeons in regional surgical care has been remarkable, and the importance of surgical education for young surgeons in the region is only increasing. However, there are very few reports about regional surgical education. This study aimed to clarify the current status and issues regarding surgical education in regional surgical care and to examine the ideal way to provide surgical education in the region. METHODS: Two questionnaire surveys were carried out. (1) "Survey on the awareness regarding the education of young surgeons" was conducted by mail in institutions where surgeons worked. (2) "Survey on the current status of surgical education for young surgeons" was conducted via the Internet with surgeons under 40 years old and mentors at the same facility. RESULTS: There were 175 respondents to survey (1), among whom 131 (75%) surgeons were interested in educating young surgeons, and 112 (64%) were actively participating in this educating. Regarding the best evaluation methods for mentors who are educating young surgeons, the most frequent answer was "I don't know (51%)". The number of respondents in survey (2) was 87, including 27 (31%) young surgeons and 60 (69%) mentors. Although there was no difference between young surgeons and mentors in the level of satisfaction with the current status of young surgeons, 37% of young surgeons in urban areas were dissatisfied with their current status, compared to 0% in the regional area (p < 0.05). CONCLUSIONS: Although surgeons did not have confidence in their own education, the level of satisfaction among young surgeons was high even in those providing regional surgical care. Development of an evaluation system for surgical education is necessary for young surgeons to receive more effective surgical education in the region.

Efficacy of pancreaticojejunostomy of the pancreatic stump during distal or central pancreatectomy.

BACKGROUND: A stapler is usually used for transection and closure of the pancreas in distal pancreatectomy (DP) or central pancreatectomy (CP). When the pancreas is transected to the right of the portal vein, it is difficult to use a stapler and clinically relevant postoperative pancreatic fistula (CR-POPF) frequently occurs. We report on the efficacy of pancreaticojejunostomy (PJ) of the pancreatic stump for patients in whom stapler use is difficult. METHODS: Patients who underwent DP or CP were enrolled in this study. The pancreas was usually transected by a stapler, and ultrasonic coagulating shears (UCS) were used depending on the tumor situation. When using UCS, hand-sewn closure or PJ was performed for the pancreatic stump. The relationship between clinicopathological factors and the methods of pancreatic transection and closure were investigated. RESULTS: In total, 164 patients underwent DP or CP, and the pancreas was transected with a stapler in 150 patients and UCS in 14 patients. The rate of CR-POPF was higher and the postoperative hospital stay was longer in the UCS group than in the stapler group. PJ of the pancreatic stump, which was performed for 7 patients, did not worsen intraoperative factors. CR-POPF was not seen in these 7 patients, which was significantly less than that with hand-sewn closure. CONCLUSIONS: PJ of the pancreatic stump during DP or CP reduces CR-POPF compared with hand-sewn closure and may be useful especially when the pancreas is transected to the right of the portal vein.

Localized colorectal cancer database integrating 4 randomized controlled trials; (JCOG2310A).

Although phase III randomized controlled trials (RCTs) represent the most robust statistical approach for answering clinical questions, they require massive expenditures in terms of time, labor, and funding. Ancillary and supplementary analyses using RCTs are sometimes conducted as alternative approaches to answering clinical questions, but the available integrated databases of RCTs are limited. In this background, the Colorectal Cancer Study Group (CCSG) of the Japan Clinical Oncology Group (JCOG) established a database of ancillary studies integrating four phase III RCTs (JCOG0212, JCOG0404, JCOG0910 and JCOG1006) conducted by the CCSG to investigate specific clinicopathological factors in pStage II/III colorectal cancer (JCOG2310A). This database will be updated by adding another clinical trial data and accelerating several analyses that are clinically relevant in the management of localized colorectal cancer. This study describes the details of this database and planned and ongoing analyses as an initiative of JCOG cOlorectal Young investigators (JOY).

Impact of the endoscopic surgical skill qualification system on conversion to laparotomy after low anterior resection for rectal cancer in Japan (a secondary analysis of the EnSSURE study).

BACKGROUND AND AIMS: Conversion to laparotomy is among the serious intraoperative complications and carries an increased risk of postoperative complications. In this cohort study, we investigated whether or not the Endoscopic Surgical Skill Qualification System (ESSQS) affects the conversion rate among patients undergoing laparoscopic surgery for rectal cancer. METHODS: We performed a retrospective secondary analysis of data collected from patients undergoing laparoscopic surgery for cStage II and III rectal cancer from 2014 to 2016 across 56 institutions affiliated with the Japan Society of Laparoscopic Colorectal Surgery. Data from the original EnSSURE study were analyzed to investigate risk factors for conversion to laparotomy by performing univariate and multivariate analyses based on the reason for conversion. RESULTS: Data were collected for 3,168 cases, including 65 (2.1%) involving conversion to laparotomy. Indicated conversion accounted for 27 cases (0.9%), while technical conversion accounted for 35 cases (1.1%). The multivariate analysis identified the following independent risk factors for indicated conversion to laparotomy: tumor diameter [mm] (odds ratio [OR] 1.01, 95% confidence interval [CI] 1.01-1.05, p = 0.0002), combined resection of adjacent organs [+/-] (OR 7.92, 95% CI 3.14-19.97, p < 0.0001), and surgical participation of an ESSQS-certified physician [-/+] (OR 4.46, 95% CI 2.01-9.90, p = 0.0002). The multivariate analysis identified the following risk factors for technical conversion to laparotomy: registered case number of institution (OR 0.99, 95% CI 0.99-1.00, p = 0.0029), institution type [non-university/university hospital] (OR 3.52, 95% CI 1.54-8.04, p = 0.0028), combined resection of adjacent organs [+/-] (OR 5.96, 95% CI 2.15-16.53, p = 0.0006), and surgical participation of an ESSQS-certified physician [-/+] (OR 6.26, 95% CI 3.01-13.05, p < 0.0001). CONCLUSIONS: Participation of ESSQS-certified physicians may reduce the risk of both indicated and technical conversion. Referral to specialized institutions, such as high-volume centers and university hospitals, especially for patients exhibiting relevant background risk factors, may reduce the risk of conversion to laparotomy and lead to better outcomes for patients. TRIAL REGISTRATION: This study was registered with the Japanese Clinical Trials Registry as UMIN000040645.

Risk factors for anastomotic leakage after low anterior resection for obese patients with rectal cancer.

PURPOSE: We aimed to analyze the risk factors for anastomotic leakage (AL) after low anterior resection (LAR) in obese patients (body mass index [BMI] ≥ 25 kg/m2) with rectal cancer. METHODS: Data were collected from four hundred two obese patients who underwent LAR for rectal cancer in 51 institutions. RESULTS: Forty-six (11.4%) patients had clinical AL. The median BMI (27 kg/m2) did not differ between the AL and non-AL groups. In the AL group, comorbid respiratory disease was more common (p = 0.025), and the median tumor size was larger (p = 0.002). The incidence of AL was 11.5% in the open surgery subgroup and 11.4% in the laparoscopic surgery subgroup. Among the patients who underwent open surgery, the AL group showed a male predominance (p = 0.04) in the univariate analysis, but it was not statistically significant in the multivariate analysis. Among the patients who underwent laparoscopic surgery, the AL group included a higher proportion of patients with comorbid respiratory disease (p = 0.003) and larger tumors (p = 0.007). CONCLUSION: Comorbid respiratory disease and tumor size were risk factors for AL in obese patients with rectal cancer. Careful perioperative respiratory management and appropriate selection of surgical procedures are required for obese rectal cancer patients with respiratory diseases.

Cytocidal Effect of Irradiation on Gastric Cancer Cells Infected with a Recombinant Mammalian Orthoreovirus Expressing a Membrane-Targeted KillerRed.

The outcomes of unresectable gastric cancer (GC) are unfavorable even with chemotherapy; therefore, a new treatment modality is required. The combination of an oncolytic virus and photodynamic therapy can be one of the promising modalities to overcome this. Mammalian orthoreovirus (MRV) is an oncolytic virus that has been used in clinical trials for several cancers. In this study, we developed and evaluated a recombinant MRV strain type 3 Dearing (T3D) that expresses membrane-targeting KillerRed (KRmem), a phototoxic fluorescent protein that produces cytotoxic reactive oxygen species upon light irradiation. KRmem was fused in-frame to the 3' end of the σ2 viral gene in the S2 segment using a 2A peptide linker, enabling the expression of multiple proteins from a single transcript. RNA electrophoresis, Western blotting, and immunofluorescence analyses confirmed functional insertion of KRmem into the recombinant virus. The growth activity of the recombinant virus was comparable to that of the wild-type MRV in a cultured cell line. The recombinant virus infected two GC cell lines (MKN45P and MKN7), and a significant cytocidal effect was observed in MKN45P cells infected with the recombinant virus after light irradiation. Thus, recombinant MRV-expressing KRmem has the potential to serve as a novel treatment tool for GC.

Characterization of residual cancer by comparison of a pair of organoids established from a patient with esophageal squamous cell carcinoma before and after neoadjuvant chemotherapy.

Neoadjuvant chemotherapy (NAC) followed by surgery is a standard approach for management of locally advanced esophageal squamous cell carcinoma (ESCC). Patients who do not respond well to NAC have a poor prognosis. Despite extensive research, the mechanisms of chemoresistance in ESCC remain largely unknown. Here, we established paired tumor organoids-designated as PreNAC-O and PostNAC-O-from one ESCC patient before and after NAC, respectively. Although the two organoids did not exhibit significant differences in proliferation, morphology or drug sensitivity in vitro, the tumorigenicity of PostNAC-O in vivo was significantly higher than that of PreNAC-O. Xenografts from PreNAC-O tended to exhibit keratinization, while those from PostNAC-O displayed conspicuous necrotic areas. The tumorigenicity of PostNAC-O xenografts during the chemotherapy was comparable to that of PreNAC-O without treatment. Furthermore, the gene expression profiles of the xenografts suggested that expression of genes involved in the EMT and/or hypoxia response might be related to the tumorigenicity of PostNAC-O. Our data suggested that the tumorigenicity of residual cancer had been enhanced, outweighing the effects of chemotherapy, rather than being attributable to intrinsic chemoresistance. Further studies are required to clarify the extent to which residual cancers share a common mechanism similar to that revealed here.

Overexpression of VSNL1 Enhances Cell Proliferation in Colorectal Carcinogenesis.

INTRODUCTION: We have previously reported that overexpression of visinin-like protein 1 (VSNL1) is frequently observed in advanced colorectal adenocarcinomas and correlates with poorer prognosis. In this study, we determined the levels of VSNL1 expression in the earlier stages of colorectal tumors including adenomas and adenocarcinomas, and attempted to clarify the functional significance of VSNL1 overexpression in colorectal carcinogenesis. METHODS: Levels of VSNL expression in colorectal tumor tissues were analyzed using immunohistochemistry. The effects of VSNL1 downregulation and overexpression on cell proliferation, resistance to apoptosis, and invasiveness were determined using two VSNL1-overexpressing colorectal cancer cell lines, CW-2 and HCT-116 and VSNL1 inducibly expressing SNU-C5, respectively. Gene expression signatures in VSNL1-downregulated CW-2 and HCT-116 were identified using transcriptome and gene set enrichment analyses. RESULTS: VSNL1 expression was restricted to only a few crypt cells in the non-tumorous epithelium, whereas it became enhanced in adenomas and adenocarcinomas with the progression of tumorigenesis. Downregulation of VSNL1 in CW-2 and HCT-116 cells suppressed their proliferation through induction of apoptosis. Conversely, overexpression of VSNL1 in SNU-C5 cells enhanced resistance to anoikis. Transcriptome and gene set enrichment analyses revealed that downregulation of VSNL1 altered the expression level of the apoptosis-related gene set in CW-2 and HCT-116 cells. CONCLUSION: VSNL1 plays a role in both the development and progression of colorectal tumors by enhancing cell viability.

Clinical significance of colonoscopy before laparoscopic bariatric/metabolic surgery in Japanese patients.

PURPOSE: Obesity is known to be associated with colorectal adenoma (CRA) and colorectal cancer (CRC); yet colonoscopy is not considered an essential preoperative evaluation before bariatric/metabolic surgery. The aim of this study was to clarify the clinical significance of preoperative colonoscopy for obese Japanese patients. METHODS: The subjects of this retrospective study were 114 patients who underwent screening colonoscopy before bariatric/metabolic surgery. Multivariate analyses were performed to evaluate the independent predictors of CRA/CRC among the characteristics identified as significant or nearly significant by univariate analyses. RESULTS: Colonoscopy revealed abnormal findings indicating the need for biopsy or polypectomy in 20 of the 114 patients (17.5%), and CRA was diagnosed in 13 patients (11.4%). Three patients (2.6%), who were all ≥ 56 years old, had a CRA ≥ 10 mm in diameter. The multivariate analysis showed that older age and male sex were significant predictors of CRA/CRC, which was identified in 46.2% of the male patients aged ≥ 46 years. CONCLUSION: Our findings suggest that older age and male sex may be risk factors for CRA/CRC in obese Japanese candidates for bariatric/metabolic surgery; thus, preoperative colonoscopy should be considered for these high-risk patients.