Automated operative phase identification in peroral endoscopic myotomy.

BACKGROUND: Artificial intelligence (AI) and computer vision (CV) have revolutionized image analysis. In surgery, CV applications have focused on surgical phase identification in laparoscopic videos. We proposed to apply CV techniques to identify phases in an endoscopic procedure, peroral endoscopic myotomy (POEM). METHODS: POEM videos were collected from Massachusetts General and Showa University Koto Toyosu Hospitals. Videos were labeled by surgeons with the following ground truth phases: (1) Submucosal injection, (2) Mucosotomy, (3) Submucosal tunnel, (4) Myotomy, and (5) Mucosotomy closure. The deep-learning CV model-Convolutional Neural Network (CNN) plus Long Short-Term Memory (LSTM)-was trained on 30 videos to create POEMNet. We then used POEMNet to identify operative phases in the remaining 20 videos. The model's performance was compared to surgeon annotated ground truth. RESULTS: POEMNet's overall phase identification accuracy was 87.6% (95% CI 87.4-87.9%). When evaluated on a per-phase basis, the model performed well, with mean unweighted and prevalence-weighted F1 scores of 0.766 and 0.875, respectively. The model performed best with longer phases, with 70.6% accuracy for phases that had a duration under 5 min and 88.3% accuracy for longer phases. DISCUSSION: A deep-learning-based approach to CV, previously successful in laparoscopic video phase identification, translates well to endoscopic procedures. With continued refinements, AI could contribute to intra-operative decision-support systems and post-operative risk prediction.

Colorectal Surgical Site Infection Prevention Kits Prior to Elective Colectomy Improve Outcomes.

INTRODUCTION: Patient compliance with preoperative mechanical and antibiotic bowel preparation, skin washes, carbohydrate loading, and avoidance of fasting are key components of successful colorectal ERAS and surgical site infection (SSI)-reduction programs. In July 2016, we began a quality improvement project distributing a free SSI Prevention Kit (SSIPK) containing patient instructions, mechanical and oral bowel preparation, chlorhexidine washes, and carbohydrate drink to all patients scheduled for elective colectomy, with the goal of improving patient compliance and rates of SSI. METHODS: This was a prospective data audit of our first 221 SSIPK+ patients, who were compared to historical controls (SSIPK-) of 1760 patients undergoing elective colectomy from January 2013 to March 2017. A 1:1 propensity score system accounted for nonrandom treatment assignment. Matched patients' complications, particularly postoperative infection and ileus, were compared. RESULTS: SSIPK+ (n = 219) and SSIPK- (n = 219) matched patients were statistically identical on demographics, comorbidities, BMI, surgical indication, and procedure. SSIPK+ patients had higher compliance with mechanical (95% vs 71%, P < 0.001) and oral antibiotic (94% vs 27%, P < 0.001) bowel preparation. This translated into lower overall SSI rates (5.9% vs 11.4%, P = 0.04). SSIPK+ patients also had lower rates of anastomotic leak (2.7% vs 6.8%, P = 0.04), prolonged postoperative ileus (5.9% vs 14.2%, P < 0.01), and unplanned intubation (0% vs 2.3%, P = 0.02). Furthermore, SSIPK+ patients had shorter mean hospital length of stay (3.1 vs 5.4 d, P < 0.01) and had fewer unplanned readmissions (5.9% vs 14.6%, P < 0.001). There were no differences in rates of postoperative pneumonia, urinary tract infection, Clostridium difficile colitis, sepsis, or death. CONCLUSION: Provision of a free-of-charge SSIPK is associated with higher patient compliance with preoperative instructions and significantly lower rates of surgical site infections, lower rates of prolonged postoperative ileus, and shorter hospital stays with fewer readmissions. Widespread utilization of such a bundle could therefore lead to significantly improved outcomes.

Third-time ("redo-redo") anti-reflux surgery: patient-reported outcomes after a thoracoabdominal approach.

BACKGROUND: Approximately 3-6% of patients undergoing anti-reflux surgery require "redo" surgery for persistent gastroesophageal reflux disease (GERD). Further surgery for patients with two failed prior anti-reflux operations is controversial due to the morbidity of reoperation and poor outcomes. We examined our experience with surgical revision of patients with at least two failed anti-reflux operations. METHODS: Adults undergoing at least a second-time revision anti-reflux surgery between 1999 and 2017 were eligible. The primary outcomes were general and disease-specific quality-of-life (QoL) scores determined by Short-Form-36 (SF36) and GERD-Health-Related QoL (GERD-HRQL) instruments, respectively. Secondary outcomes included perioperative morbidity and mortality. RESULTS: Eighteen patients undergoing redo-redo surgery (13 with 2 prior operations, 5 with 3 prior operations) were followed for a median of 6 years [IQR 3, 12]. Sixteen patients (89%) underwent open revisions (14 thoracoabdominal, 2 laparotomy) and two patients had laparoscopic revisions. Indications for surgery included reflux (10 patients), regurgitation (5 patients), and dysphagia (3 patients). Intraoperative findings were mediastinal wrap herniation (9 patients), misplaced wrap (2 patients), mesh erosion (1 patient), or scarring/stricture (6 patients). Procedures performed included Collis gastroplasty + fundoplication (6 patients), redo fundoplication (5 patients), esophagogastrectomy (4 patients), and primary hiatal closure (3 patients). There were no deaths and 13/18 patients (72%) had no postoperative complications. Ten patients completed QoL surveys; 8 reported resolution of reflux, 6 reported resolution of regurgitation, while 4 remained on proton-pump inhibitors (PPI). Mean SF36 scores (± standard deviation) in the study cohort in the eight QoL domains were as follows: physical functioning (79.5 [± 19.9]), physical role limitations (52.5 [± 46.3]), emotional role limitations (83.3 [± 36.1]), vitality (60.0 [± 22.7]), emotional well-being (88.4 [± 8.7]), social functioning (75.2 [± 31.0]), pain (66.2 [± 30.9]), and general health (55.0 [± 39.0]). CONCLUSION: An open thoracoabdominal approach in appropriately selected patients needing third-time anti-reflux surgery carries low morbidity and provides excellent results as reflected in QoL scores.

Computer Vision Analysis of Intraoperative Video: Automated Recognition of Operative Steps in Laparoscopic Sleeve Gastrectomy.

OBJECTIVE(S): To develop and assess AI algorithms to identify operative steps in laparoscopic sleeve gastrectomy (LSG). BACKGROUND: Computer vision, a form of artificial intelligence (AI), allows for quantitative analysis of video by computers for identification of objects and patterns, such as in autonomous driving. METHODS: Intraoperative video from LSG from an academic institution was annotated by 2 fellowship-trained, board-certified bariatric surgeons. Videos were segmented into the following steps: 1) port placement, 2) liver retraction, 3) liver biopsy, 4) gastrocolic ligament dissection, 5) stapling of the stomach, 6) bagging specimen, and 7) final inspection of staple line. Deep neural networks were used to analyze videos. Accuracy of operative step identification by the AI was determined by comparing to surgeon annotations. RESULTS: Eighty-eight cases of LSG were analyzed. A random 70% sample of these clips was used to train the AI and 30% to test the AI's performance. Mean concordance correlation coefficient for human annotators was 0.862, suggesting excellent agreement. Mean (±SD) accuracy of the AI in identifying operative steps in the test set was 82% ±â€Š4% with a maximum of 85.6%. CONCLUSIONS: AI can extract quantitative surgical data from video with 85.6% accuracy. This suggests operative video could be used as a quantitative data source for research in intraoperative clinical decision support, risk prediction, or outcomes studies.

Timing of Carotid Endarterectomy After Stroke: Retrospective Review of Prospectively Collected National Database.

OBJECTIVE: Our objective was to identify the postoperative risk associated with different timing intervals of repair. BACKGROUND: Timing of carotid intervention in poststroke patients is widely debated with the scales balanced between increased periprocedural risk and recurrent neurologic event. National database reviews show increased risk to patients treated within the first 2 days of a neurologic event compared to those treated after 6 days. METHODS: Utilizing Vascular Quality Initiative data, all carotid interventions performed on stroke patients between the years 2012 and 2017 were queried. Patients were then stratified based on the timing of surgery from their stroke (<48 hours, 3-7 days, 8-14 days, >15 days). Major outcomes included postoperative stroke, death, and myocardial infarction. RESULTS: A total of 8404 patients were included being predominantly men (5281, 62.8%), with an average age of 69 (±10). Patients treated at greater than 8 days showed significantly less risk of postoperative combined stroke/death and postoperative stroke. There were no significant differences in postoperative stroke or death between the 8 to 14 and greater than 15 days groups.Multivariate regression analysis showed that delayed timing of surgery between 3 and 7 days was protective for postoperative stroke/death (P = 0.003) and any postoperative complication (P = 0.028). Delaying surgery to more than 8 days after stroke was protective for postoperative stroke/death (P < 0.001), postoperative stroke (P < 0.001), and any postoperative complication (P < 0.001). CONCLUSIONS: Carotid revascularization should occur no sooner than 48 hours after index stroke event. Surgeons should strive to operate between 8 and 14 days to protect against postoperative stroke/death.

The impact of neoadjuvant therapy for gastroesophageal adenocarcinoma on postoperative morbidity and mortality.

BACKGROUND AND OBJECTIVES: We sought to study the impact of neoadjuvant therapy (NAT) on postoperative complications following surgical resection of adenocarcinomas of the stomach and gastroesophageal junction (GEJ). METHODS: We compared the postoperative outcomes of 308 patients undergoing a surgery-first approach and 145 patients undergoing NAT followed by curative-intent surgery for adenocarcinomas of the stomach and GEJ from 1995-2014. RESULTS: Patients receiving NAT were more likely to be younger, have tumors of the GEJ, to undergo esophagogastrectomy and D2 lymphadenectomy, and to have more advanced stage disease than patients undergoing surgery first. There were no differences in overall 30-day morbidity or mortality rates between the groups, yet patients undergoing surgery first were more likely to have higher-grade complications than those undergoing NAT. Age >65 years, higher ASA score, concomitant splenectomy, more advanced tumor stage, and year of surgery were independent risk factors for postoperative morbidity, but receipt of NAT was not an independent predictor of postoperative morbidity. CONCLUSIONS: Despite having more advanced disease and undergoing higher-risk surgical procedures, patients with adenocarcinomas of the stomach or GEJ who receive NAT prior to surgery are no more likely to suffer postoperative complications than patients treated with a surgery-first approach. J. Surg. Oncol. 2016;113:560-564. © 2016 Wiley Periodicals, Inc.

Evaluation of the LINX antireflux procedure.

PURPOSE OF REVIEW: To evaluate the current data on the safety, efficacy, and indications for magnetic sphincter augmentation (MSA) using the LINX device to treat gastroesophageal reflux disease (GERD). RECENT FINDINGS: The LINX device has demonstrated excellent safety and GERD efficacy in several recent nonblinded, single arm studies with strict inclusion criteria and up to 3 years follow-up. Dysphagia has been the most common adverse effect occurring after LINX. Other gastrointestinal side-effects seen after laparoscopic fundoplication (bloating, gas, and inability to belch) may be less common after LINX. SUMMARY: The LINX device is a safe, well tolerated, and effective therapy for GERD in the short term. MSA should be considered for selected GERD patients without significant anatomic or motility defects. However, the long-term safety and efficacy of LINX - both alone and in comparison to current GERD therapies - remains to be determined.

A comparative trial of laparoscopic magnetic sphincter augmentation and Nissen fundoplication.

BACKGROUND: Laparoscopic magnetic sphincter augmentation (MSA) with the LINX device is a promising new therapy for the treatment of gastroesophageal reflux disease (GERD). Initial studies have demonstrated MSA to be safe and effective. However, no direct comparison between MSA and laparoscopic Nissen fundoplication (LNF), the gold standard surgical therapy for GERD, has been performed. METHODS: A single institution, case-control study was conducted of MSA performed from 2012 to 2013 and a cohort of LNF matched for age, gender, and hiatal hernia size. RESULTS: MSA and LNF were both effective treatments for reflux with 75 and 83 % of patients, respectively, reporting resolution of GERD at short-term follow-up. Dysphagia was common following both MSA and LNF, but severe dysphagia requiring endoscopic dilation was more frequent after MSA (50 vs. 0 %, p = 0.01). Need for dilation did not correlate with size of the LINX device or any other examined patient factors. A trend toward decreased adverse GI symptoms of bloating, flatulence, and diarrhea was seen after MSA compared to LNF (0 vs. 33 %). MSA had a shorter operative time (64 vs. 90 min, p < 0.01) but other peri-operative outcomes, including pain, morbidity, and re-admissions were equivalent to LNF. MSA patients were more likely to be self-referred (58 vs. 0 %, p < 0.001). CONCLUSIONS: MSA and LNF are both effective and safe treatments for GERD; however, severe dysphagia requiring endoscopic intervention is more common with MSA. Other adverse GI side effects may be less frequent after MSA. Consideration should be paid to these distinct post-operative symptom profiles when selecting a surgical therapy for reflux disease.

Endoscopic simulator curriculum improves colonoscopy performance in novice surgical interns as demonstrated in a swine model.

INTRODUCTION: The purpose of this study was to determine whether independent virtual endoscopic training accelerates the acquisition of endoscopic skill by novice surgical interns. METHODS: Nine novice surgical interns participated in a prospective study comparing colonoscopy performance in a swine model before and after an independent simulator curriculum. An independent observer evaluated each intern for the ability to reach the cecum within 20 min and technical ability as determined by Global Assessment of Gastrointestinal Endoscopic Skills--Colonoscopy (GAGES-C) score and performance compared. In addition, at the conclusion of training, a post test of two basic simulated colonoscopy modules was completed and metrics evaluated. As a control, three attending physicians who routinely perform colonoscopy also completed colonoscopy in the swine model. RESULTS: Prior to endoscopic training, one (11 %) intern successfully intubated the cecum in 19.56 min. Following training, six (67 %) interns reached the cecum with mean time of 9.2 min (p < 0.05). Statistically significant improvement was demonstrated in four out of five GAGES-C criteria. All three experts reached the cecum, with a mean time of 4.40 min. Comparison of expert and post-curriculum intern times demonstrated the experts to be significantly faster (p < 0.05). Comparison of interns who were and were not able to reach the cecum following the simulator curriculum demonstrated significantly improved GI Mentor™ performance in the efficiency (79 vs. 67.1 %, p = 0.05) and time to cecum (3.37 vs. 5.59 min, p = 0.01) metrics. No other significant difference was demonstrated in GAGES-C categories or other simulator parameter. CONCLUSION: Simulator training on the GI Mentor™ alone significantly improved endoscopic skills in novice surgical interns as demonstrated in a swine model. This study also identified parameters on the GI Mentor™ that could indicate 'clinical readiness'. This study supports the role for endoscopic simulator training in surgical resident education as an adjunct to clinical experience.

Incidence and predictors of adenocarcinoma following endoscopic ablation of Barrett's esophagus.

BACKGROUND: The rate and risk factors of recurrent or metachronous adenocarcinoma following endoscopic ablation therapy in patients with Barrett's esophagus (BE) have not been specifically reported. AIM: The aim of this study was to determine the incidence and predictors of adenocarcinoma after ablation therapy for BE high-grade dysplasia (HGD) or intramucosal carcinoma (IMC). METHODS: This is a single center, retrospective review of prospectively collected data on consecutive cases of endoscopic ablation for BE. A total of 223 patients with BE (HGD or IMC) were treated by ablation between 1996 and 2011. Primary outcome measures were recurrence and new development of adenocarcinoma after ablation. Recurrence was defined as the presence of adenocarcinoma following the absence of adenocarcinoma in biopsy samples from two consecutive surveillance endoscopies. Logistic regression analysis was performed to assess predictors of adenocarcinoma after ablation. RESULTS: One hundred and eighty-three patients were included in the final analysis, and 40 patients were excluded: 22 for palliative ablation, eight lost to follow-up, five for residual carcinoma and five for postoperative state. Median follow-up was 39 months. Recurrence or new development of adenocarcinoma was found in 20 patients (11 %) and the median time to recurrence/development of adenocarcinoma was 11.5 months. Independent predictors of recurrent or metachronous adenocarcinoma were hiatal hernia size ≥ 4 cm (odds ratio 3.649, P = 0.0233) and histology (HGD/adenocarcinoma) after first ablation (odds ratio 4.141, P = 0.0065). CONCLUSIONS: Adenocarcinoma after endoscopic therapy for HGD or IMC in BE is associated with large hiatal hernia and histology status after initial ablation therapy.

Preoperative cetuximab, irinotecan, cisplatin, and radiation therapy for patients with locally advanced esophageal cancer.

PURPOSE: To determine the efficacy and toxicity of weekly neoadjuvant cetuximab combined with irinotecan, cisplatin, and radiation therapy in patients with locally advanced esophageal or gastroesophageal junction cancer. METHODS AND MATERIALS: Patients with stage IIA-IVA esophageal or gastroesophageal junction cancer were enrolled in a Simon's two-stage phase II study. Patients received weekly cetuximab on weeks 0-8 and irinotecan and cisplatin on weeks 1, 2, 4, and 5, with concurrent radiotherapy (50.4 Gy on weeks 1-6), followed by surgical resection. RESULTS: In the first stage, 17 patients were enrolled, 16 of whom had adenocarcinoma. Because of a low pathologic complete response (pCR) rate in this cohort, the trial was discontinued for patients with adenocarcinoma but squamous cell carcinoma patients continued to be enrolled; two additional patients were enrolled before the study was closed as a result of poor accrual. Of the 19 patients enrolled, 18 patients proceeded to surgery, and 16 patients underwent an R0 resection. Three patients (16%) had a pCR. The median progression-free survival interval was 10 months, and the median overall survival duration was 31 months. Severe neutropenia occurred in 47% of patients, and severe diarrhea occurred in 47% of patients. One patient died preoperatively from sepsis, and one patient died prior to hospital discharge following surgical resection. CONCLUSIONS: This schedule of cetuximab in combination with irinotecan, cisplatin, and radiation therapy was toxic and did not achieve a sufficient pCR rate in patients with localized esophageal adenocarcinoma to undergo further evaluation.

D2 lymphadenectomy with surgical ex vivo dissection into node stations for gastric adenocarcinoma can be performed safely in Western patients and ensures optimal staging.

BACKGROUND: The AJCC recommends examination of >16 nodes to stage gastric adenocarcinoma. D2 lymphadenectomy (LAD) followed by surgical ex vivo dissection (SEVD) into nodal stations is standard at many high-volume Asian centers, but potential increases in morbidity and mortality have slowed adoption of D2 LAD in some Western centers. METHODS: A total of 331 patients with gastric adenocarcinoma who underwent surgical resection at one Western institution from 1995 to 2010 were examined. RESULTS: Median age of patients was 69 years old, 65% were male, and 84% were white. D1 LAD was performed in 285 patients (86%) and D2 LAD in 46 patients (14%), with SEVD being performed in 17 patients (37%) in the D2 group. D2 LAD with or without SEVD was performed much more commonly between 2006 and 2010. For the D1, D2 without SEVD, and D2 with SEVD groups, the median number of examined nodes and percentage with >16 examined nodes were 16 and 51%, 27 and 93%, and 40 and 100%, respectively. Major complications occurred in 16% of the D1 group and 17% of the D2 group (p>0.05), and 30-day mortality was 3% for the D1 group and 0% for the D2 group. D2 LAD was a positive prognostic factor for overall survival on univariate (p=0.027) and multivariate analyses (p=0.005), but there were several possible confounding variables. CONCLUSIONS: D2 LAD at our Western institution was performed with low morbidity and no mortality. Optimal staging occurred after D2 LAD combined with SEVD, where a median of 40 nodes were examined and all patients had >16 examined nodes.

Noncurative gastrectomy for gastric adenocarcinoma should only be performed in highly selected patients.

BACKGROUND: The benefit of surgical resection in patients with incurable gastric adenocarcinoma is controversial. METHODS: A total of 289 patients who presented with advanced or metastatic gastric cancer from 1995 to 2010 were retrospectively reviewed. RESULTS: Ten patients (3.5 %) required emergent surgery at presentation and were excluded from further analyses. Patients who underwent nonemergent surgery at presentation (n = 110, 38.1 %) received either gastric resection (group A, n = 46, 42 %) or surgery without resection (group B, n = 64, 58 %). Procedures in group A included distal gastrectomy (n = 25, 54 %), total gastrectomy (n = 17, 37 %), and proximal/esophagogastrectomy (n = 4, 9 %). Procedures in group B included laparoscopy (n = 17, 27 %), open exploration (n = 25, 39 %), gastrostomy and/or jejunostomy tube (n = 12, 19 %), and gastrojejunostomy (n = 10, 16 %). Group A required a stay in the intensive care unit or additional invasive procedure significantly more often than group B (15 vs. 2 %, p = 0.009). Four patients in group A (8.7 %) and three patients in group B (4.7 %) died within 30 days of surgery (p = 0.45). When the 110 patients who underwent nonemergent surgery (groups A and B) were compared to nonoperatively managed patients (group C, n = 169, 58 %), median overall survival did not significantly differ (8.6 vs. 9.2 vs. 7.7 months; p > 0.05). Three patients in group B (4.7 %) and three in group C (1.8 %) ultimately required an operation for their primary tumor. CONCLUSIONS: Patients with gastric adenocarcinoma who present with advanced or metastatic disease not amenable to curative resection infrequently require emergent surgery. Noncurative resection is associated with significant perioperative morbidity and mortality as well as limited overall survival, and should therefore be performed judiciously.

Minilaparoscopy-assisted transrectal low anterior resection (LAR): a preliminary study.

BACKGROUND: Natural orifice translumenal endoscopic surgery (NOTES) represents the evolution of surgery towards less invasive procedures. The feasibility of NOTES transrectal approach has increased its clinical applicability. This report describes a first series of minilaparoscopy-assisted transrectal low anterior resection with double purse-string end-to-end circular stapler anastomoses. METHODS: Between March and April 2012 three selected patients underwent transrectal minilaparoscopy-assisted natural orifice surgery total mesorectal excision for rectal cancer. All the oncologic principles of open/laparoscopic low anterior resection for rectal cancer were strictly fulfilled. Two patients underwent neoadjuvant treatment. Laparoscopic visualization and assistance was provided through one 10-mm umbilical port and two ports, one of which was used as stoma site (5 mm) and the other as a drain site (2 mm needle port). The specimen was transected transanally followed by the confection of double purse-string lateral/end-to-end anastomoses. There were no intraoperative complications. RESULTS: Mean operative time was 143 min. Oral intake was initiated on the second postoperative day. Patients were discharged home by day 5. The pathology unit confirmed that distal and circumferential margins were free of tumor invasion, and quality of mesorectum resection was reported satisfactory. One patient had to be readmitted because of severe dehydration due to increased ileostomy output. The patient was discharged at the third day after the readmission without renal failure. CONCLUSIONS: In this preliminary report, transrectal minilaparoscopy-assisted low anterior resection was feasible and safe. Lateral/end-to-end anastomoses can be considered an interesting alternative to the double-stapling technique. However, it is necessary to further study and develop these procedures, along with careful patient selection, before transrectal low anterior resection may be considered for routine clinical use.

Novel challenges of multi-society investigator-initiated studies: a paradigm shift for technique and technology evaluation.

The introduction of innovative techniques and novel technologies into clinical practice is a challenge that confronts all aspects of healthcare delivery. Upheaval from shrinking research funding and declining healthcare reimbursements now forces patients, doctors, hospitals, payers, regulators, and even health systems into conflict as new therapies struggle to find a place in the therapeutic armamentarium. The escalating costs of healthcare force all parties to consider both the medical risks/benefits as well as the economic efficiency of proposed tools and therapies. We highlight these challenges by examining the process of initiating and conducting a "society-as-investigator" clinical trial to assess the safety of the natural orifice translumenal endoscopic surgery (NOTES) approach to cholecystectomy in the context of the issues that confront technology diffusion today.

Transanal natural orifice transluminal endoscopic surgery (NOTES) rectal resection: "down-to-up" total mesorectal excision (TME)--short-term outcomes in the first 20 cases.

BACKGROUND: The transanal minilaparoscopy-assisted natural orifice transluminal endoscopic surgery (NOTES) approach holds significant promise as a safe and less morbid alternative to conventional low anterior rectal resection. Previous reports have shown satisfactory short-term oncologic results. We evaluated the safety and short-term outcomes in rectal cancer subjects who underwent transanal minilaparoscopy-assisted natural orifice surgery total mesorectal excision (TME) rectal resection. METHODS: Twenty selected patients with rectal cancer were enrolled onto a prospective study of minilaparoscopy-assisted natural orifice surgery TME rectal resection. The study endpoints were safety of access (intra- or postoperative morbidity) and adequacy of oncological resection criteria; intact TME; distal and circumferential margins; and number of lymph nodes retrieved. RESULTS: All procedures were successfully completed with the transanal NOTES and minilaparoscopy technique. The mean age was 65 ± 10 years; 55% of patients were male; the mean body mass index was 25.3 ± 3.8 kg/m(2). Thirty-five percent of tumors were in the distal rectum, 50% in midrectum, and 15% in proximal rectum. Coloanal anastomoses were hand sewn in 65% and stapled in 35%. Mean operative time was 235 ± 56 min. There were no procedure-related complications. Pathologic analysis demonstrated negative distal and circumferential margins in all patients. An average of 15.9 ± 4.3 lymph nodes were retrieved. The mesorectal fascia was intact in all the specimens. CONCLUSIONS: This study demonstrates that transanal NOTES with minilaparoscopic assistance in the hands of a specialized team is safe; meets the oncologic requirements for high-quality rectal cancer surgery; and may offer advantages over pure laparoscopic approaches for visualizing and dissecting out the distal mesorectum. Minilaparoscopic assistance allows one to compensate for the limitations of current NOTES instrumentation to ensure the safety and adequacy of oncologic resection in these difficult cases. Careful patient selection, a specialized team, and long-term outcome evaluation are critical before this procedure can be considered for routine clinical use.

Transanal rectosigmoid resection via natural orifice translumenal endoscopic surgery (NOTES) with total mesorectal excision in a large human cadaver series.

BACKGROUND: The authors' group has previously described successful transanal rectosigmoid resection via natural orifice translumenal endoscopic surgery (NOTES) in both porcine and cadaveric models using the transanal endoscopic microsurgery platform. This report describes the largest cadaveric series to date as optimization of this approach for clinical application continues. METHODS: Between December 2008 and September 2011, NOTES transanal rectosigmoid resection with total mesorectal excision (TME) was successfully performed in 32 fresh human cadavers using transanal dissection alone (n = 19), with transgastric endoscopic assistance (n = 5), or with laparoscopic assistance (n = 8). The variables recorded were gender, body mass index (BMI), operative time, length of the mobilized specimen, integrity of the mesorectum and the resected specimen, and complications. Univariate statistical analysis was performed. RESULTS: Of the 32 cadavers, 22 were male with a mean BMI of 24 kg/m(2) (range 16.3-37 kg/m(2)). The mean operative time was 5.1 h (range 3-8 h), and the mean specimen length was 53 cm (range 15-91.5 cm). After the first five cadavers, specimen length significantly improved, and a trend toward decreased operative time was demonstrated. The mesorectum was intact in 100% of the specimens. In nine cadavers, endoscopic dissection was complicated by organ injury. Evaluation by the operative approach demonstrated a significantly longer specimen with laparoscopic assistance (67.7 cm) than with transgastric assistance (45.4 cm) or transanal dissection alone (49.2 cm) (p = 0.013). Comparison of the technique used for inferior mesenteric pedicle division demonstrated both significantly decreased operative time (4.8 vs 6 h; p = 0.024) and increased specimen length (57.7 vs 39.6 cm; p = 0.025) when a stapler was used in lieu of a bipolar cautery device. CONCLUSION: Transanal NOTES rectosigmoid resection with TME is feasible and demonstrates improvement in specimen length and operative time with experience. Transitioning to clinical application requires laparoscopic assistance to overcome limitations related to NOTES instrumentation, as well as procedural training with fresh human cadavers.

A pilot study of natural orifice transanal endoscopic total mesorectal excision with laparoscopic assistance for rectal cancer.

BACKGROUND: The objective of this pilot study was to evaluate the feasibility and safety of natural orifice endoscopic transanal total mesorectal excision (TME) with laparoscopic assistance in a cohort study of five patients with stage I and IIA rectal cancer. METHODS: Five eligible patients with node-negative rectal cancer located 4-12 cm from the anal verge were enrolled in an IRB-approved pilot study. All patients underwent transanal endoscopic TME with laparoscopic assistance, hand-sewn coloanal anastomosis, and a diverting loop ileostomy. Primary and secondary end points included adequacy of the mesorectal excision and 30-day postoperative complications, respectively. RESULTS: Between November 2011 and May 2012, three males and two females underwent transanal endoscopic TME with laparoscopic assistance. Patient mean age and BMI were 48.6 ± 9.8 years and 25.7 ± 2.3 kg/m(2), respectively. Tumors were located an average of 5.7 ± 2.4 cm from the anal verge and preoperatively staged as T1N0M0 (2), T2N0M0 (1), and T3N0M0 (2). Mean operative time was 274.6 ± 85.4 min with no intraoperative complications. Partial intersphincteric resection was performed in conjunction with transanal endoscopic TME in three patients. Pathologic examination of TME specimens demonstrated complete mesorectal excision in all cases with negative proximal, distal, and radial margins. Mean length of hospital stay was 5.2 ± 2.6 days and three minor complications occurred, including one ileus and two cases of transient urinary dysfunction. At a mean early follow-up of 5.4 ± 2.3 months, all patients remain disease-free. CONCLUSIONS: In this pilot study of five patients with rectal cancer, transanal endoscopic TME with laparoscopic assistance is feasible and safe, and is a promising alternative to open and laparoscopic TME. Evaluation of long-term functional and oncologic outcomes of this approach is needed before widespread adoption can be recommended.

Comparison of a lymph node ratio-based staging system with the 7th AJCC system for gastric cancer: analysis of 18,043 patients from the SEER database.

OBJECTIVES: The American Joint Committee on Cancer (AJCC) staging system for gastric cancer bases N status on absolute number of metastatic nodes, regardless of the number of examined nodes. We examined a modified staging system utilizing node ratio (Nr), the ratio of metastatic to examined nodes. METHODS: A total of 18,043 gastric cancer patients who underwent gastrectomy were identified from the US Surveillance, Epidemiology, and End Results (SEER) database. A training set was divided into 5 Nr groups, and a TNrM staging system was constructed. Median survival and overall survival, based on 7th edition AJCC and TNrM staging systems, were compared, and the analysis was repeated in a validation set. RESULTS: Median examined nodes were 10 to 11. For the training set, overall survival for all 5 AJCC N categories was significantly different when subgrouped into 15 or fewer versus more than 15 examined nodes, but overall survival was similar regardless of the number of examined nodes in 4 of 5 Nr categories. Seven AJCC stages had statistically different overall survival between subgroups, whereas only 1 TNrM stage had statistically different overall survival between subgroups. When misclassification was defined as any subgroup in which median survival fell outside the 95% confidence interval of the group's overall median survival, AJCC staging misclassified 57% of patients and TNrM staging misclassified only 12%. Similar results were found in the validation set. CONCLUSIONS: The AJCC system classifies SEER gastric cancer patients into stages in which subgroups often have wide variations in survival. For patients undergoing limited lymph node analysis, the proposed TNrM system may predict survival more accurately.