Identification of lateral pelvic nodes without metastasis in patients with rectal cancer treated with preoperative chemoradiotherapy or chemotherapy based on magnetic resonance imaging.

Background: Intensive localized therapy is promising for the treatment of rectal cancer. In Japan, chemoradiotherapy (CRT) and neoadjuvant chemotherapy (NAC) are used as preoperative treatments for this disease. Magnetic resonance imaging (MRI) is used to diagnose lateral pelvic node (LPN) metastases, but the changes in LPN findings on MRI following preoperative treatment are unclear. Furthermore, there may be patients in whom LPN dissection can be omitted after CRT/NAC. Methods: Patients who underwent total mesorectal excision with LPN dissection after CRT/NAC at 13 Japanese Society for Cancer of the Colon and Rectum member institutions between 2017 and 2019 were included. Changes in the short diameter of the LPNs after CRT/NAC and the reduction rate were examined. Results: A total of 101 LPNs were examined in 28 patients who received CRT and 228 in 47 patients who received NAC. Comparison of LPNs before and after CRT/NAC showed that most LPNs shrank after CRT but that the size reduction was variable after NAC. Although some LPNs with a short diameter of <5 mm showed residual metastasis, no metastases were observed in LPNs that were <5 mm in short diameter before and after CRT/NAC and did not shrink after treatment. Conclusion: Although the short diameter of LPNs was significantly reduced by both CRT and NAC, even LPNs with a short diameter of <5 mm could have residual metastases. However, dissection may be omitted for LPNs <5 mm in short diameter that do not shrink after preoperative CRT or NAC.

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.

Low-grade appendiceal mucinous neoplasm penetrating sigmoid colon: A case report.

Low-grade appendiceal mucinous neoplasm (LAMN) is principally characterized by low-grade cytology without evidence of invasion to other organs. We report a LAMN surgical case whose appendiceal tumor penetrated the sigmoid colon wall. An 87-year-old man was referred for endoscopic resection (ER) of a colon polyp. Despite four ERs over 5 years, the polyp recurred at the same site. Laparoscopic surgery revealed a dilated appendix firmly attached to the sigmoid colon. We performed en bloc resection of both the sigmoid colon and appendix without tumor exposure. The histopathological evaluation showed that the LAMN had penetrated the sigmoid colon wall, forming two polyps on the colonic mucosa. In cases where the appendiceal-colonic fistula is suspected, en bloc resection of the appendix and colon wall should be considered.

The potential of an artificial intelligence for diagnosing MRI images in rectal cancer: multicenter collaborative trial.

BACKGROUND: An artificial intelligence-based algorithm we developed, mrAI, satisfactorily segmented the rectal tumor, rectum, and mesorectum from MRI data of rectal cancer patients in an initial study. Herein, we aimed to validate mrAI using an independent dataset. METHODS: We utilized MRI images collected in another nationwide research project, "Open versus Laparoscopic Surgery for Advanced Low Rectal Cancer Patients". MRIs from 467 cases with upfront surgery were utilized; six radiologists centralized the MRI evaluations. The diagnostic accuracies of mrAI and the radiologists for tumor depth were compared using pathologic diagnosis as a reference. RESULTS: For all cases, centralized diagnosis demonstrated 84.2% sensitivity, 37.7% specificity, and 73.7% accuracy; mrAI exhibited 70.6% sensitivity, 61.3% specificity, and 68.5% accuracy. After limiting MRIs to those acquired by a Philips scanner, with an inter-slice spacing of ≤ 6 mm-both conditions similar to those used in the development of mrAI-the performance of mrAI improved to 76.8% sensitivity, 76.7% specificity, and 76.7% accuracy, while the centralized diagnosis showed 81.8% sensitivity, 36.7% specificity, and 71.3% accuracy. Regarding relapse-free survival, the prognosis for tumors staged ≥ T3 was significantly worse than for tumors staged ≤ T2 (P = 0.0484) in the pathologic diagnosis. While no significant difference was observed between ≥ T3 and ≤ T2 tumors in the centralized diagnosis (P = 0.1510), the prognosis for ≥ T3 was significantly worse in the mrAI diagnosis (P = 0.0318). CONCLUSION: Proper imaging conditions for MRI can enhance the accuracy of mrAI, which has the potential to provide feedback to radiologists without overestimating tumor stage.

Long-term Outcome After Surgical Resection of Paraaortic Lymph Node Metastasis of Colorectal Cancer: A Multicenter Retrospective Study.

BACKGROUND: The significance of resection of paraaortic lymph node metastasis in colorectal cancer is controversial. OBJECTIVE: To clarify the prognosis of colorectal cancer after paraaortic lymph node metastasis resection. DESIGN: Multicenter retrospective study. SETTINGS: Thirty-six institutions in Japan participated in this study. PATIENTS: Patients with resected and pathologically proven paraaortic lymph node metastasis of CRC between 2010 and 2015. DATA SOURCES: Database and medical records at each institution. MAIN OUTCOME MEASURES: Overall survival after paraaortic lymph node metastasis resection, recurrence-free survival, and recurrence patterns after R0 resection of paraaortic lymph node metastasis. RESULTS: A total of 133 patients were included in the primary analysis population in this study. The 5-year overall survival rate (95% confidence interval [CI]) was 41.0% (32.0, 49.8), and the median survival (95% CI) was 4.1 (3.4, 4.7) years. Independent prognostic factors for overall survival were the pathological T stage (pT4 vs. pT1- 3, adjusted hazard ratio [aHR]: 1.91, p = 0.006), other organ metastasis (present vs. absent, aHR: 1.98, p = 0.005), time to metastases (synchronous vs. metachronous, aHR: 2.02, p = 0.02), and number of paraaortic lymph node metastasis (≥3 vs. <3, aHR: 2.13, p = 0.001). The 5-year recurrence-free survival rate (95% CI) was 21.1% (13.5, 29.7), with a median (95% CI) of 1.2 (0.9, 1.4) years. The primary tumor location (left- vs. right-sided colon, aHR: 4.77, p = 0.01; rectum vs. right-sided colon, aHR: 5.27, p = 0.006), other organ metastasis (present vs. absent, aHR: 1.90, p = 0.03), number of paraaortic lymph node metastasis (≥3 vs. <3, aHR: 2.20, p = 0.001), and hospital volume (<10 vs. ≥10, aHR: 2.18, p = 0.02) were identified as independent prognostic factors for recurrence-free survival. Paraaortic lymph node recurrence was the most common at 33.3%. LIMITATIONS: Selection bias cannot be ruled out because of the retrospective nature of the study. CONCLUSIONS: Less than three paraaortic lymph node metastasis was a favorable prognostic factor for both overall survival and recurrence-free survival. However, paraaortic lymph node metastases were considered to be a systemic disease and the significance of resection was limited. See Video Abstract.

Appendiceal neoplasms derived from appendiceal tip remnants following appendectomy: a report of two cases.

BACKGROUND: Neoplasms derived from remnant appendix are rarely described, with most cases arising from the appendiceal "stump". Here, we present two surgical cases of appendiceal neoplasms derived from appendiceal "tip" remnants. CASE PRESENTATION: The first patient was a 71-year-old man who had undergone laparoscopic appendectomy for acute appendicitis 12 years prior. During appendectomy, the appendiceal root was ligated, but the appendix was not completely removed due to severe inflammation. At the most recent presentation, computed tomography (CT) was performed to examine choledocholithiasis, which incidentally revealed a cystic lesion of approximately 90 mm adjacent to the cecum. A retrospective review revealed that the cystic lesion had increased in size over time, and laparoscopic ileocecal resection was performed. Pathology revealed no continuity from the appendiceal orifice to the cyst, and a diagnosis of low-grade appendiceal mucinous neoplasm (LAMN) was made from the appendiceal tip remnant. The patient was discharged without complications. The second patient was a 65-year-old man who had undergone surgery for peritonitis due to severe appendicitis 21 years prior. During this operation, the appendix could not be clearly identified due to severe inflammation; consequently, cecal resection was performed. He was referred to our department with a chief complaint of general fatigue and loss of appetite and a cystic lesion of approximately 85 mm close to the cecum that had increased over time. CT showed irregular wall thickening, and malignancy could not be ruled out; therefore, laparoscopic ileocecal resection with D3 lymph node dissection was performed. The pathological diagnosis revealed mucinous adenocarcinoma (TXN0M0) arising from the remnant appendiceal tip. The patient is undergoing follow-up without postoperative adjuvant chemotherapy, with no evidence of pseudomyxoma peritonei or cancer recurrence for 32 months postoperatively. CONCLUSIONS: If appendicitis-associated inflammation is sufficiently severe that accurate identification of the appendix is difficult, it may remain on the apical side of the appendix, even if the root of the appendix is ligated and removed. If the appendectomy is terminated incompletely, it is necessary to check for the presence of a residual appendix postoperatively and provide appropriate follow-up.

Local Recurrence of Rectal Cancer After Transanal Total Mesorectal Excision and Risk Factors: A Nationwide Multicenter Cohort Study in Japan.

Objective: To investigate the oncological outcomes after transanal total mesorectal excision (TaTME) for rectal cancer and risk factors for local recurrence (LR). Background: A high LR rate with a multifocal pattern early after TaTME has been reported in Norway and the Netherlands, causing controversy over the oncological safety of this technique. Methods: Twenty-six member institutions of the Japan Society of Laparoscopic Colorectal Surgery participated in this retrospective cohort study. A total of 706 patients with primary rectal cancer who underwent TaTME between January 2012 and December 2019 were included for analysis. The primary endpoint was the cumulative 3-year LR rate. Results: A total of 253 patients had clinical stage III disease (35.8%) and 91 (12.9%) had stage IV. Intersphincteric resection was performed in 318 patients (45.0%) and abdominoperineal resection in 193 (27.3%). There was 1 urethral injury (0.1%). A positive resection margin (R1) was seen in 42 patients (5.9%). Median follow-up was 3.42 years, and the 2- and 3-year cumulative LR rates were 4.95% (95% confidence interval: 3.50-6.75) and 6.82% (95% confidence interval: 5.08-8.89), respectively. A multifocal pattern was observed in 14 (25%) of 56 patients with LR. Tumor height from the anal verge, pathological T4 disease, pathological stage III/IV, positive perineural invasion, and R1 resection were significant risk factors for LR in multivariable analysis. Conclusions: In this selected cohort in which intersphincteric resection or abdominoperineal resection was performed in more than half of cases, oncological outcomes were acceptable during a median follow-up of more than 3 years.

Right-sided versus left-sided colorectal cancer in elderly patients: a sub-analysis of a large multicenter case-control study in Japan.

PURPOSE: This study investigated the impact of sidedness of colorectal cancer (CRC) in elderly patients on the prognosis. METHODS: In a sub-analysis of a multicenter case-control study of CRC patients who underwent surgery at ≥ 80 years old conducted in Japan between 2003 and 2007, both short- and long-term outcomes were compared between right-sided colon cancers (RCCs) and left-sided colorectal cancers (LCCs). RCCs were defined as those located from the cecum to the transverse colon. RESULTS: Among the 1680 patients who underwent curative surgery, 812 and 868 had RCCs and LCCs, respectively. RCCs were more frequent than LCCs in those who were female, had renal comorbidities, and had a history of abdominal surgery. Regarding tumor characteristics, RCCs were larger, invaded more deeply, and were diagnosed as either mucinous or signet ring-cell carcinoma more frequently than LCCs. Regarding the prognosis, patients with RCCs had a significantly longer cancer-specific survival (CS-S) and cancer-specific relapse-free survival (CS-RFS) than those with LCCs. Furthermore, sidedness was determined to be an independent prognostic factor for CS-S and CS-RFS. CONCLUSION: RCCs, which accounted for half of the cases in patients ≥ 80 years old, showed better long-term outcomes than LCCs.

Real-time detection of active bleeding in laparoscopic colectomy using artificial intelligence.

BACKGROUND: Most intraoperative adverse events (iAEs) result from surgeons' errors, and bleeding is the majority of iAEs. Recognizing active bleeding timely is important to ensure safe surgery, and artificial intelligence (AI) has great potential for detecting active bleeding and providing real-time surgical support. This study aimed to develop a real-time AI model to detect active intraoperative bleeding. METHODS: We extracted 27 surgical videos from a nationwide multi-institutional surgical video database in Japan and divided them at the patient level into three sets: training (n = 21), validation (n = 3), and testing (n = 3). We subsequently extracted the bleeding scenes and labeled distinctively active bleeding and blood pooling frame by frame. We used pre-trained YOLOv7_6w and developed a model to learn both active bleeding and blood pooling. The Average Precision at an Intersection over Union threshold of 0.5 (AP.50) for active bleeding and frames per second (FPS) were quantified. In addition, we conducted two 5-point Likert scales (5 = Excellent, 4 = Good, 3 = Fair, 2 = Poor, and 1 = Fail) questionnaires about sensitivity (the sensitivity score) and number of overdetection areas (the overdetection score) to investigate the surgeons' assessment. RESULTS: We annotated 34,117 images of 254 bleeding events. The AP.50 for active bleeding in the developed model was 0.574 and the FPS was 48.5. Twenty surgeons answered two questionnaires, indicating a sensitivity score of 4.92 and an overdetection score of 4.62 for the model. CONCLUSIONS: We developed an AI model to detect active bleeding, achieving real-time processing speed. Our AI model can be used to provide real-time surgical support.

Midesophageal diverticulum with elevated intrabolus pressure: a case report.

BACKGROUND: Esophageal diverticulum is commonly associated with esophageal motility disorders, which can be diagnosed using high-resolution manometry (HRM) according to the Chicago classification. Although midesophageal diverticulum (M-ED) is associated with inflammatory processes, esophageal motility disorders have been recently identified as an etiology of M-ED. CASE PRESENTATION: We present the case of a patient with M-ED and elevated intrabolus pressure (IBP), which did not meet the criteria for esophageal motility disorders according to the Chicago classification. A 71-year-old man presented with gradually worsening dysphagia for two years and was diagnosed as having an 8-cm-long M-ED and multiple small diverticula in lower esophagus. HRM revealed a median integrated relaxation pressure of 14.6 mmHg, a distal latency of 6.4 s, and an average maximum IBP of 35.7 mmHg. He underwent thoracoscopic resection of the M-ED and myotomy, which successfully alleviated the symptoms and reduced the intrabolus pressure to normal levels. CONCLUSIONS: It is important to recognize the esophageal diverticulum pathology with HRM findings even in cases where the results may not meet the Chicago classification and to include myotomy based on the results.

Evaluation of the advantage of surgeons certified by the endoscopic surgical skill qualification system participating in laparoscopic low anterior rectal resection.

Background: A technical qualification system was developed in 2004 by the Japan Society for Endoscopic Surgery. An analysis of the EnSSURE study on 3188 stage II-III rectal cancer patients, which was performed by including the participation of qualified surgeons as assistants and advisers without restricting their participation as operators, revealed that the participation of technically qualified surgeons in surgery improved the technical and oncological safety of laparoscopic rectal resection. Aim: This secondary retrospective analysis of the EnSSURE study examined the advantage of qualified surgeons participating in laparoscopic low anterior resection (LAR). Methods: The outcomes of low anterior resection were compared between groups with and without the participation of surgeons qualified by the Endoscopic Surgical Skill Qualification System (Q and non-Q groups, respectively). We used propensity score matching to generate paired cohorts at a one-to-one ratio. The postoperative complication rate, short-term results (hemorrhage volume, operative time, number of dissected lymph nodes, open conversion rate, intraoperative complication rate, and R0 resection rate), and long-term results (disease-free survival rate, local recurrence rate, and overall survival rate) were evaluated. Results: The frequencies of postoperative complications, anastomotic bleeding, and intraperitoneal abscess were significantly lower, the operative time was significantly shorter, the postoperative hospital stay was significantly shorter, and the number of dissected lymph nodes was higher in the Q group. No significant differences were observed in disease-free survival, local recurrence, or overall survival rate rates between the groups. Conclusion: The participation of qualified surgeons in LAR is technically advantageous.

Utility of articulating instruments as an alternative to robotic devices in laparoscopic right hemicolectomy.

Laparoscopic complete mesocolic excision with central vessel ligation has been widely accepted for its oncological benefits in colon cancer surgery. However, laparoscopic right hemicolectomy involves a risk for vascular injury during dissection around the surgical trunk. This technical difficulty has been attributed to the limited movement of conventional laparoscopic forceps. Although robotic devices can overcome the restricted motion of laparoscopic devices, they are not yet widely used. The ArtiSential is an articulating laparoscopic instrument that has a two-joint end-effector that enables a wide range of motion precisely reflecting the surgeon's finger movements, and is designed to compensate for the drawbacks of conventional laparoscopic tools. The present study demonstrated the utility of articulating instruments in laparoscopic right hemicolectomy by comparing the authors' laparoscopic procedures, using articulating instruments, with robotic procedures. Articulating laparoscopic instruments can be successfully maneuvered in virtually the same manner as robotic devices and, as such, represent a viable alternative to robotic surgery. Supplementary Information: The online version contains supplementary material available at 10.1007/s13691-024-00654-w.

Histological differentiation between sporadic and colitis-associated intestinal cancer in a nationwide study: A propensity-score-matched analysis.

BACKGROUND AND AIM: Colitis-associated intestinal cancer (CAC) can develop in patients with inflammatory bowel disease; however, the malignant grade of CAC may differ from that of sporadic colorectal cancer (CRC). Therefore, we compared histological findings distinct from cancer stage between CAC and sporadic CRC to evaluate the features of CAC. METHODS: We reviewed the clinical and histological data collected from a nationwide database in Japan between 1983 and 2020. Patient characteristics were compared to distinguish ulcerative colitis (UC), Crohn's disease (CD), and sporadic CRC. Comparisons were performed by using all collected data and propensity score-matched data. RESULTS: A total of 1077 patients with UC-CAC, 297 with CD-CAC, and 136 927 with sporadic CRC were included. Although the prevalence of well or moderately differentiated adenocarcinoma (Tub1 and Tub2) decreased according to tumor progression for all diseases (P < 0.01), the prevalence of other histological findings, including signet ring cell carcinoma, mucinous carcinoma, poorly differentiated adenocarcinoma, or squamous cell carcinoma, was significantly higher in CAC than in sporadic CRC. Based on propensity score-matched data for 982 patients with UC and 268 with CD, the prevalence of histological findings other than Tub1 and Tub2 was also significantly higher in those with CAC. At pT4, mucinous carcinoma occurred at a significantly higher rate in patients with CD (45/86 [52.3%]) than in those with sporadic CRC (13/88 [14.8%]) (P < 0.01). CONCLUSION: CAC, including early-stage CAC, has a higher malignant grade than sporadic CRC, and this difference increases in significance with tumor progression.

Impact of the coronavirus disease 2019 pandemic on gastric and colorectal cancer surgeries: a multicenter epidemiologic study from the Kinki region of Japan.

The coronavirus disease 2019 pandemic affected cancer surgeries and advanced cancer diagnoses; however, the trends in patient characteristics in medical institutions during this time, and the surgical approaches used are unclear. We investigated the impact of the pandemic on gastric and colorectal cancer surgeries in the Kinki region of Japan. We grouped 1688 gastric and 3493 colorectal cancer surgeries into three periods: "pre-pandemic" (April 2019-March 2020), "pandemic 1" (April 2020-March 2021), and "pandemic 2" (April 2021-September 2021), to investigate changes in the number of surgeries, patient characteristics, surgical approaches, and cancer progression after surgery. Gastric and colorectal cancer surgeries decreased from the pre-pandemic levels, by 20% and 4%, respectively, in pandemic 1, and by 31% and 19%, respectively, in pandemic 2. This decrease had not recovered to pre-pandemic levels by September, 2021. Patient characteristics, surgical approaches, and cancer progression of gastric and colorectal surgeries did not change remarkably as a result of the coronavirus disease 2019 pandemic.

Identification of complications requiring interventions after gastrointestinal cancer surgery from real-world data: An external validation study.

Background: Recently, real-world data have been recognized to have a significant role for research and quality improvement worldwide. The decision on the existence or nonexistence of postoperative complications is complex in clinical practice. This multicenter validation study aimed to evaluate the accuracy of identification of patients who underwent gastrointestinal (GI) cancer surgery and extraction of postoperative complications from Japanese administrative claims data. Methods: We compared data extracted from both the Diagnosis Procedure Combination (DPC) and chart review of patients who underwent GI cancer surgery from April 2016 to March 2019. Using data of 658 patients at Kyoto University Hospital, we developed algorithms for the extraction of patients and postoperative complications requiring interventions, which included an invasive procedure, reoperation, mechanical ventilation, hemodialysis, intensive care unit management, and in-hospital mortality. The accuracy of the algorithms was externally validated using the data of 1708 patients at two other hospitals. Results: In the overall validation set, 1694 of 1708 eligible patients were correctly extracted by DPC (sensitivity 0.992 and positive predictive value 0.992). All postoperative complications requiring interventions had a sensitivity of >0.798 and a specificity of almost 1.000. The overall sensitivity and specificity of Clavien-Dindo ≥grade IIIb complications was 1.000 and 0.995, respectively. Conclusion: Patients undergoing GI cancer surgery and postoperative complications requiring interventions can be accurately identified using the real-world data. This multicenter external validation study may contribute to future research on hospital quality improvement or to a large-scale comparison study among nationwide hospitals using real-world data.

Analysis of the characteristics and outcomes of patients with pseudomyxoma peritonei of appendiceal origin treated with curative-intent surgery.

BACKGROUND: There are no previous studies on pseudomyxoma peritonei regarding the details of surgical procedures included in cytoreductive surgery and quantitative evaluation for peritoneal metastases by region in the abdominal cavity. This study aimed to describe the characteristics and procedural details involved in cytoreductive surgery, and survival outcomes of patients with pseudomyxoma peritonei originating from appendiceal mucinous neoplasm, and identify differences in the difficulty of cytoreductive surgery based on tumor location. METHODS: Patient characteristics and survival outcomes were studied through a retrospective review. The complete cytoreduction rate (i), the 5-year survival rate for patients with complete cytoreduction (ii), and an index as a complement (i × ii × 100) were described for patients who had tumors larger than 50 mm in one of the 13 regions of the abdominal cavity. RESULTS: A total of 989 patients were treated with curative-intent cytoreductive surgery. The median peritoneal cancer index was 18 (interquartile range, 6-29), with complete cytoreduction achieved in 702 patients (71%); the major complication rate was 17%. The median overall survival was 92.9 months, compared to 53.8 months for patients who underwent total gastrectomy and 30.4 months for those who underwent total colectomy. In the 13 abdominal regions, the index scores indicating cytoreduction difficulty were categorized into three risk groups: upper and mid-abdominal (>20), lateral abdominal (10-20), and small bowel (<10). CONCLUSIONS: Cytoreductive surgery offered favorable survival outcomes, even in cases involving total gastrectomy. The difficulty of achieving complete cytoreduction varied across abdominal regions and was classified into three levels.

Management of Patients Receiving Antiplatelet Therapy During Gastroenterological Surgery: A Multicenter Prospective Cohort Study (GSATT).

OBJECTIVE: This study aimed to evaluate the effect of continuing preoperative aspirin monotherapy on surgical outcomes in patients receiving antiplatelet therapy (APT). SUMMARY BACKGROUND DATA: The effectiveness of continuing preoperative aspirin monotherapy in patients undergoing APT in preventing thromboembolic consequences is mostly unknown. METHODS: This prospective multicenter cohort study on the Safety and Feasibility of Gastroenterological Surgery in Patients Undergoing Antithrombotic Therapy (GSATT study) conducted at 14 clinical centers enrolled and screened patients between October 2019 and December 2021. The participants (n=1,170) were assigned to the continued APT group, discontinued APT group, or non-APT group, and the surgical outcomes of each group were compared. Propensity score matching was performed between the continued and discontinued APT groups to investigate the effect of continuing preoperative aspirin therapy on thromboembolic complications. RESULTS: The rate of thromboembolic complications in the continued APT group was substantially lower than that in the non-APT or discontinued APT groups (0.5% vs. 2.6% vs. 2.9%; P=0.027). Multivariate investigation of the entire cohort revealed that discontinuation of APT (P<0.001) and chronic anticoagulant use (P<0.001) were independent risk factors for postoperative thromboembolism. The post-matching evaluation demonstrated that the rates of thromboembolic complications were significantly different between the continued and discontinued APT groups (0.6% vs. 3.3%; P=0.012). CONCLUSIONS: APT discontinuation following elective gastroenterological surgery increases the risk of thromboembolic consequences, whereas continuing preoperative aspirin greatly reduces this risk. The continuation of preoperative aspirin therapy in APT-received patients is considered one of the best alternatives for preventing thromboembolism during elective gastroenterological surgery.

Impact of laparoscopic surgery on short-term and long-term outcomes in elderly obese patients with colon cancer.

Background: Laparoscopic surgery is reported to be useful in obese or elderly patients with colon cancer, who are at increased risk of postoperative complications because of comorbidities and physical decline. However, its usefulness is less clear in patients who are both elderly and obese and may be at high risk of complications. Methods: Data for obese patients (body mass index ≥25) who underwent laparoscopic or open surgery for stage II or III colon cancer between January 2009 and December 2013 were collected by the Japan Society of Laparoscopic Colorectal Surgery. Surgical outcomes, postoperative complications, and relapse-free survival (RFS) were compared between patients who underwent open surgery and those who underwent laparoscopic surgery according to whether they were elderly (≥70 y) or nonelderly (<70 y). Results: Data of 1549 patients (elderly, n = 598; nonelderly, n = 951) satisfied the selection criteria for analysis. Length of stay was shorter and surgical wound infection was less common in elderly obese patients who underwent laparoscopic surgery than in those underwent open surgery. There were no significant between-group differences in overall complications, anastomotic leakage, ileus/small bowel obstruction, or RFS. There were also no significant differences in RFS after laparoscopic surgery according to patient age. Conclusion: Laparoscopic surgery is safe in elderly obese patients with colon cancer and does not worsen their prognosis. There was no significant difference in the effectiveness of laparoscopic surgery between obese patients who were elderly and those who were nonelderly.