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.

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.

Preoperative chemoradiotherapy versus postoperative chemoradiotherapy for local advanced gastric or Siewert II/III GEJ cancer: A retrospective analysis

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Background: Radiation therapy has improved survival in gastric cancer in some randomized trials. However, post-operative fields have been difficult tolerate, and completion rates have been low. Preoperative therapy may afford the opportunity to radical therapy, and potentially improve the resectability in advanced patients. Methods: Patients with Siewert II/III GE junction or gastric cancer treated at Massachusetts General Hospital were evaluated with Institutional Review Board approval. Clinical parameters and prognostic factors including gender, age, clinical stage, pathological stage, radiation parameters, concurrent chemotherapy, non-radiation chemotherapy, toxicity and survival were included in the analysis. Results: From Jul 2005 to Jan 2017, we enrolled 88 patients had chemoradiotherapy (CRT) and surgery, 48 preoperative and 40 postoperative CRT patients. In the preoperative group, 16.7% (8/48) had nodes outside a standard D2 dissection range, and the pathologic complete regression (pCR) rate was 18.8% (9/48). Median preoperative and postoperative radiation dose was 50.4 Gy and 45 Gy. Two-drug regimen was the most commonly used preoperative concurrent chemotherapy: 60.5% and single drug was the most commonly used postoperative concurrent chemotherapy: 97.5%. Except concurrent chemotherapy, 25 preoperative CRT patients received induction FOLFOX (median 8 cycles); 9 postoperative CRT patients also received 5-FU and 23 received FOLFOX (or EOX) chemotherapy. The estimated 3-year relapse-free survival (RFS) and overall survival (OS) in the preoperative and postoperative group was 51% vs. 34.3% (p = 0.286), and 71.2% vs. 45.9% (p = 0.179), respectively. In preoperative CRT group, there was more hematological toxicity but less gastrointestinal toxicity than postoperative CRT group, more distant metastasis but less peritoneal recurrence rate. Conclusions: Compared to postoperative chemoradiotherapy, preoperative chemoradiotherapy option has the trend of better tolerance, higher RFS and OS in patients with local advanced gastric cancer. Different chemoradiotherapy strategy may lead to different recurrence patterns.

Lower Esophageal Sphincter Augmentation for Gastroesophageal Reflux Disease: The Safety of a Modern Implant

INTRODUCTION

Use of the magnetic sphincter augmentation device (MSAD) for gastroesophageal reflux disease (GERD) is increasing. As this innovative treatment for GERD gains widespread use and adoption, an assessment of its safety since U.S. market introduction is presented.

METHODS

Events were collected from the Manufacturer and User Facility Device Experience (MAUDE) database, which reports events submitted to the Food and Drug Administration (FDA) of suspected device-associated deaths, serious injuries, and malfunctions. The reporting period was from March 22, 2012 (FDA approval) through May 31, 2016, and included only events occurring in the United States. Additional information was provided by the manufacturer, allowing calculation of implant rates and durations.

RESULTS

An estimated 3283 patients underwent magnetic sphincter augmentation (165 surgeons at 191 institutions). The median implant duration was 1.4 years, with 1016 patients implanted for at least 2 years. No deaths, life-threatening events, or device malfunctions were reported. The overall rate of device removal was 2.7% (89/3283). The most common reasons for device removal were dysphagia (52/89) and persistent reflux symptoms (19/89). Removal for erosion and migration was 0.15% (5/3283) and 0% (0/3283), respectively. There were no perforations. Of the device removals, 57.3% (51/89) occurred <1 year after implant, 30.3% (27/89) between 1 and 2 years, and 12.4% (11/89) >2 years after implant. The rate of device removal and erosion with an implant duration >2 years were 1.1% (11/1016) and 0.1% (1/1016), respectively. All device removals and erosions were managed nonemergently, with no complications or long-term consequences.

CONCLUSIONS

During a 4-year period in more than 3000 patients, no unanticipated MSAD complications have emerged, and there is no data to suggest a trend of increased events over time. The presentation and management of device-related issues have been less complicated than revisions for laparoscopic fundoplication or other interventions for GERD. MSAD is considered safe for the widespread treatment of GERD.

Predictors of Lymph Node Metastasis in Western Early Gastric Cancer

BACKGROUND

The application of endoscopic and local resection for early gastric cancer (EGC) is limited by the risk of regional lymph node (LN) metastasis. We sought to determine the incidence and predictors of LN metastasis in a contemporary cohort of Western patients with early gastric cancer.

METHODS

Sixty-seven patients with pT1 gastric adenocarcinoma underwent radical surgery without neoadjuvant therapy at our institution between 1995 and 2011, and clinicopathologic factors predicting LN metastasis were analyzed.

RESULTS

LN metastases were present in 15/67 (22 %) pT1 tumors, including 1/23 (4 %) T1a tumors and 14/44 (32 %) T1b tumors. Tumor size, site, degree of differentiation, macroscopic tumor sub-classification, perineural invasion status, and depth of submucosal tumor penetration did not predict LN metastasis. The presence of lymphovascular invasion (LVI) and positive nodal status by endoscopic ultrasound (EUS) were the only factors that predicted LN metastasis on multivariate analysis. T1a tumors without LVI had a 0 % rate of positive LN, whereas T1b tumors with LVI had a 64.3 % rate of positive LN.

CONCLUSIONS

EGC limited to the mucosa, without evidence of LVI, and N0 on EUS, may be considered for limited resection. However, any EGC with submucosal invasion, LVI, or positive nodes on EUS should undergo radical resection with lymphadenectomy.

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.

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

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Background: The effects of neoadjuvant chemotherapy (CTX) or chemoradiotherapy (CTX-RT) on postoperative complications following surgical resection of adenocarcinomas of the stomach and gastroesophageal junction (GEJ) have not been well studied. Methods: We identified 308 patients undergoing a surgery-first approach and 145 patients undergoing neoadjuvant therapy (CTX, n = 73 and CTX-RT, n = 72) followed by curative-intent surgeryfor adenocarcinomas of the stomach and GEJ from 1995-2014. We compared the baseline characteristics and the postoperative outcomes between the two groups using univariate and multivariate analyses. Results: Patients receiving neoadjuvant therapy were significantly more likely to be of younger median age (63 y vs. 71 y), have tumors of the GEJ (37% vs. 17%), to undergo esophagogastrectomy (51% vs. 26%) and D2 lymphadenectomy (39% vs. 27%), 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 neoadjuvant therapy and surgery-first groups, respectively (Table). However, patients undergoing surgery first were significantly more likely to have higher-grade complications than those undergoing neoadjuvant therapy. Conclusions: Despite having more advanced disease and undergoing higher-risk surgical procedures, patients with adenocarcinomas of the stomach or GEJ who receive neoadjuvant therapy prior to surgery are less likely to have major post-operative complications than patients treated with a surgery-first approach. Concerns about higher rates of post-operative complications should not deter the use of neoadjuvant therapy for gastroesophageal cancer. [Table: see text]

The influence of anesthesia on heart rate complexity during elective and urgent surgery in 128 patients

BACKGROUND

As an emerging "new vital sign," heart rate complexity (by sample entropy [SampEn]) has been shown to be a useful trauma triage tool by predicting occult physiologic compromise and need for life-saving interventions. Sample entropy may be confounded by anesthesia possibly limiting its value intraoperatively. We investigated the effects of anesthesia on SampEn during elective and urgent surgical procedures. We hypothesized that SampEn is reduced by general anesthesia.

METHODS

With institutional review board-approved waiver of informed consent, 128 patients undergoing elective or urgent general surgery were prospectively enrolled. Real-time heart rate complexity was calculated using SampEn through electrocardiogram recordings of 200 consecutive beats in a continuous sliding-window fashion. We recorded SampEn starting 10 minutes before induction until 10 minutes after emergence from anesthesia. The time before induction of anesthesia was categorized as period 1, the time after induction and before emergence as period 2 (intraoperative), and the time after emergence as period 3. We analyzed SampEn changes as patients moved between the different periods and made 3 comparisons: from period 1 with period 2 (comparison A), from period 2 with period 3 (comparison B). We also compared period 1 with period 3 SampEn (comparison C).

RESULTS

The mean SampEn value for all patients before induction of anesthesia was 1.55 ± 0.58. In each 1 of the 3, comparisons there was a decline in SampEn. Comparison A had a mean decrease of 0.53 ± 0.55 (P < .0001), comparison B had a decrease of 0.13 ± 0.52 (P < .0051), and the mean SampEn difference for comparison C was 0.66 ± 0.53 (P < .0001). Certain pharmacologics had significant effect on SampEn as did need for urgent surgery and American Society of Anesthesiologists class.

CONCLUSION

Sample entropy decreases after induction of anesthesia and continues to decrease even immediately after emergence in patients without any immediately life-threatening conditions. This finding may complicate interpretation low complexity as a predictor of life-saving interventions in patients in the perioperative period.

Will there be a good general surgeon when you need one?

The Public Policy & Advocacy Committee sponsored the panel on the topic of "Will There Be a General Surgeon When You Need One?" at the 2012 Annual Meeting of the SSAT. The panel of experts was convened to formulate recommendations to help general surgeons adapt to the changing landscape which will undoubtedly affect the practice of surgery in the future. The invited speakers were Drs. David Hoyt, Carlos Pellegrini, Kaye M. Reid-Lombardo, and David Rattner. The session was moderated by Drs. Ross Goldberg and Tara Kent. The invited presentations and audience commentary are the basis of this manuscript.

Factors influencing readmission after curative gastrectomy for gastric cancer

BACKGROUND

The incidence of, and associated risk factors for, readmission after potentially curative gastrectomy for patients with gastric cancer has not been well studied. We sought to determine the 30-day readmission rate as well as the potential risk factors for readmission at our institution in patients undergoing gastrectomy for gastric cancer with curative intent.

STUDY DESIGN

We performed a retrospective analysis of all patients undergoing potentially curative gastrectomy for gastric cancer from 1995 to 2011. The 30-day hospital readmission rate was determined, and potential clinicopathologic risk factors for readmission were examined.

RESULTS

Readmission to the hospital within 30 days occurred in 14.6% (61 of 418) of patients, including 6 patients who were readmitted more than once. The most common reasons for readmission included nutritional difficulties (n =12, 20%), intra-abdominal fluid collections (n = 11, 18%), and small bowel obstruction (n = 6, 10%). Factors associated with a higher 30-day readmission rate included type of resection (total gastrectomy, 23% vs subtotal gastrectomy, 13% vs esophagogastrectomy, 9%, p = 0.016), pre-existing cardiovascular disease (17%, p = 0.05), and history of a major postoperative complication (24%, p < 0.001). Factors not associated with a higher readmission rate included advanced age, pre-existing pulmonary disease, T or N stage, extent of lymph node dissection, receipt of neoadjuvant chemotherapy or radiotherapy, length of stay of the index hospitalization, and destination and level of support on discharge.

CONCLUSIONS

Readmission after potentially curative gastrectomy for gastric cancer is common. Patients with pre-existing cardiovascular disease, those who suffer major postoperative complications, and those undergoing total gastric resections are at especially high risk for readmission, and strategies designed to support these high-risk patients on discharge are warranted.

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.

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.

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.

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.

Patient perception of natural orifice transluminal endoscopic surgery in an endoscopy screening program in Korea

PURPOSE

Natural orifice transluminal endoscopic surgery (NOTES) is a new method of accessing intracavitary organs in order to minimize pain by avoiding incisions in the body wall. The aim of this study is to determine patients' acceptance of NOTES in Korea and to compare their views about laparoscopic surgery and NOTES for benign and malignant diseases.

MATERIALS AND METHODS

The target number of total subjects was calculated to be 540. The subjects were classified into 18 sub-groups based on age groups, gender, and history of prior surgery. The questionnaire elicited information about demographic characteristics, medical check-ups, diseases, endoscopic and surgical histories, marital status and childbirth, the acceptance of NOTES, and the preferred routes for NOTES. In addition, the subjects chose laparoscopic surgery or NOTES for a hypothetical cholecystectomy and rectal cancer surgery, and responded to questions regarding the acceptable complication rate of NOTES, the appropriate cost of NOTES, and the reason(s) why they did not select NOTES.

RESULTS

486 of 540 patients (90.0%) who agreed to participate in this study completed the questionnaire. NOTES was preferred by the following patients: elderly; a history of treatment due to a disease; having regular check-ups; and a history of an endoscopic procedure (p<0.05). The most preferred route for NOTES was the stomach (67.1%). Eighty-four percent of the patients choosing NOTES responded that the complication rate of the new surgical method should be the same or lower than laparoscopic surgery. Vague anxiety over a new surgical method was the most common reason why NOTES was not selected in benign and malignant diseases (64% and 73%), respectively.

CONCLUSION

Patients appear to be interested in the potential benefits of NOTES and would embrace it if their concerns about safety are met. We believe that qualified surgical endoscopists can meet these safety concerns, and that NOTES development has the potential to flourish.

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.

Comparative study of complete and partial omentectomy in radical subtotal gastrectomy for early gastric cancer

PURPOSE

Curative surgery for patients with advanced or even early gastric cancer can be defined as resection of the stomach and dissection of the first and second level lymph nodes, including the greater omentum. The aim of this study was to evaluate the short- and long- term outcomes of partial omentectomy (PO) as compared with complete omentectomy (CO).

MATERIALS AND METHODS

Seventeen consecutive open distal gastrectomies with POs were initially performed between February and July in 2006. The patients' clinicopathologic data and post-operative outcomes were retrospectively compared with 20 patients who underwent open distal gastrectomies with COs for early gastric cancer in 2005.

RESULTS

The operation time in PO group was significantly shorter than that in CO group (142.4 minutes vs. 165.0 minutes, p=0.018). The serum albumin concentration on the first post-operative day in PO group was significantly higher than CO group (3.8 g/dL vs. 3.5 g/dL, p=0.018). Three postoperative minor complications were successfully managed with conservative treatment. Median follow-up period between PO and CO was 38.1 and 37.7 months. All patients were alive without recurrence until December 30, 2009.

CONCLUSION

PO during open radical distal gastrectomy can be considered a more useful procedure than CO for treating early gastric cancer. To document the long-term technical and oncologic safety of this procedure, a large-scale prospective randomized trial will be needed.

Looking ahead: the SSAT strategic plan for the next decade

The Society for Surgery of the Alimentary Tract's (SSAT) mission is to advance the science and practice of surgery in the treatment of digestive disease. An essential core value of the SSAT is multidisciplinary collaboration with both its sister societies in the Digestive Disease Week (DDW) Council and other surgical societies in Gastrointestinal Surgery. In order to achieve the society's goals, the strategic plan rests on the society's values of interdisciplinary collaboration, scholarship, education, and discovery. The strategic plan also creates a meritocracy system to foster the development of future leaders for both the SSAT and the broader house of surgery. In the short term, this plan will: Re-organize committee structure and reporting responsibilities; Clarify committee goals and deliverables; Facilitate member participation in the committees and governance of the society; Enhance member services by utilizing enhanced communication strategies; Accelerate efforts to meet the Maintenance of Certification needs of the membership; Re-focus the SSAT's energy on Quality and Outcome Assessment of GI surgery; Clarify and standardize the methodology for allocating funds for new projects. Over the course of the next few years, the SSAT will: Develop a financial model that increases revenue to support the expanded tasks the society intends to undertake; Play an active role in developing the evolving training paradigms for gastrointestinal surgeons through the continuum from residency, fellowship, and early mentored practice; Continue to support development of surgeon scientists through Career Development Award; Enhance relationship with the SSAT Foundation; Continue to improve the experience of members attending DDW; Develop surgeons interested in public policy to be leaders at a national level. The strategic plan is ambitious, and the current leadership realizes that all the tasks and objectives cannot be accomplished in 1 year. There is much to do in order to keep the SSAT the premier professional society for gastrointestinal surgery. Changes in the external environment may require modifications of the priorities or the plan itself in the coming years. Implicit in this plan is the need for annual review by the Board of Trustees at the May Board Meeting so that modifications can be made as the world around us changes.

A prospective, randomized trial of esophageal submucosal tunnel closure with a stent versus no closure to secure a transesophageal natural orifice transluminal endoscopic surgery access site

BACKGROUND

Secure esophagotomy closure methods are a critical element in the advancement of transesophageal natural orifice transluminal endoscopic surgery (NOTES) procedures.

OBJECTIVE

To compare the clinical outcomes in swine receiving an esophageal stent or no stent after a submucosal tunnel NOTES access procedure.

DESIGN

Prospective, randomized, controlled trial in 10 Yorkshire swine.

SETTING

Academic center.

INTERVENTION

An endoscopic mucosectomy device was used to create an esophageal mucosal defect. An endoscope was advanced through a submucosal tunnel into the mediastinum and thorax, and diagnostic mediastinoscopy and thoracoscopy were performed. Ten animals were randomized to no stenting (n = 5) or stenting (n = 5) with a prototype small-intestine submucosa-covered stent.

MAIN OUTCOME MEASUREMENTS

Gross and histologic appearance of the mucosectomy and esophagotomy sites as well as clinical outcomes.

RESULTS

There was a significant difference in the overall procedure time between the animals that received a stent (35.0 min, range 27-46.0 min) and those with no closure (19.0 min, range 17-32 min) (P value = .018). The unstented group achieved endoscopic and histologic evidence of complete re-epithelialization and healing (100%) at the mucosectomy site compared with the stented group (20%, P = .048). Stent migration into the stomach occurred in two swine. Both groups had complete closure of the submucosal tunnel and well-healed esophagotomy sites.

LIMITATIONS

Animal study, small number of subjects.

CONCLUSION

The placement of a covered esophageal stent significantly interferes with mucosectomy site healing.

The effect of neoadjuvant chemoradiation therapy on the prognostic value of lymph nodes after rectal cancer surgery

BACKGROUND

Neoadjuvant therapy may affect the prognostic impact of total lymph node harvests and lymph node positivity after surgery for rectal cancer.

METHODS

We performed a retrospective review of 390 consecutive patients with histologically confirmed rectal cancer. Postoperative follow-up evaluation and survival were confirmed via medical record review. The impacts of lymph node positivity and total lymph node harvest on survival and recurrence are reflected as proportional hazard ratios (HRs).

RESULTS

A total of 221 patients underwent neoadjuvant therapy, of whom 75 had positive nodes. Node-positive patients showed a significantly shorter survival time (HR, 2.89; P = .002) and time to local recurrence (HR, 6.36; P = .031) compared with patients without positive nodes. Survival and recurrence were not significantly different between patients with a total harvest of fewer than 12 nodes and patients with a higher lymph node harvest.

CONCLUSIONS

After neoadjuvant treatment and total mesorectal excision, lymph node positivity is associated with significantly shorter survival and time to local recurrence in rectal cancer patients, whereas absolute total lymph node harvests likely have little impact on prognosis.

Endoscopic transesophageal mediastinal lymph node dissection and en bloc resection by using mediastinal and thoracic approaches (with video)

BACKGROUND

The criterion standard for sampling mediastinal lymph nodes is cervical mediastinoscopy. Current methods that require transthoracic or cervical incisions can result in significant postoperative pain.

OBJECTIVE

To determine the feasibility of a novel, transesophageal endoscopic technique for mediastinal lymph node dissection and en bloc resection.

DESIGN

Nonsurvival and survival animal study.

SETTING

Animal trial at a tertiary-care academic center.

SUBJECTS

This study involved 12 Yorkshire swine.

INTERVENTION

An endoscopic cap band mucosectomy device was used to create an esophageal mucosal defect. By using the tip of the endoscope and biopsy forceps, a submucosal tunnel was fashioned, and, within the submucosal space, a hook-knife incised the muscular esophageal wall. The endoscope was then advanced into the mediastinum and chest. Mediastinoscopy and thoracoscopy were performed to identify lymph node stations. Prototype endoscopic devices permitted lymph node dissection prior to removal with an electrocautery snare. A covered prototype stent was placed over the mucosectomy site.

MAIN OUTCOME MEASUREMENTS

Feasibility of endoscopic transesophageal lymphadenectomy.

RESULTS

Three lymph nodes (1 para-aortic and 2 right paratracheal) were removed in the 3 nonsurvival swine. Nine swine were survived for 14 days (range 13-14 days) and had a total of 7 lymph nodes (2 para-aortic and 5 paratracheal) removed. Two swine had no endoscopically visible lymph nodes in the mediastinum or chest. Lymph node dissection and resection was successful in all cases where lymph nodes were identified. Lymphadenectomy was completed in a median time of 20.0 minutes (range 8-60 minutes); median total procedure time was 70.0 minutes (range 28-105 minutes). Median lymph node size was 1.1 cm (range 0.6-1.4 cm).

LIMITATIONS

Animal study.

CONCLUSION

An endoscopic transesophageal approach can accomplish mediastinal lymph node dissection and en bloc resection and provides architecturally intact lymph node specimens for histologic examination.

Stent placement provides safe esophageal closure in thoracic NOTES(TM) procedures

BACKGROUND

Safe esophageal closure remains a challenge in transesophageal Natural Orifice Transluminal Endoscopic Surgery (NOTES). Previously described methods, such as suturing devices, clips, or submucosal tunneling, all have weaknesses. In this survival animal series, we demonstrate safe esophageal closure with a prototype retrievable, antimigration stent.

METHODS

Nine Yorkshire swine underwent thoracic NOTES procedures. A double-channel gastroscope equipped with a mucosectomy device was used to create an esophageal mucosal defect. A 5-cm submucosal tunnel was created and the muscular esophageal wall was incised with a needle-knife. Mediastinoscopy and thoracoscopy were performed in all swine; lymphadenectomy was performed in seven swine. A prototype small intestinal submucosal (SurgiSIS(®)) covered stent was deployed over the mucosectomy site and tunnel. Three versions of the prototype stent were developed. Prenecropsy endoscopy confirmed stent location and permitted stent retrieval. Explanted esophagi were sent to pathology.

RESULTS

Esophageal stenting was successful in all animals. Stent placement took 15.8 ± 4.8 minuted and no stent migration occurred. Prenecropsy endoscopy revealed proximal ingrowth of esophageal mucosa and erosion with Stent A. Mucosal inflammation and erosion was observed proximally with Stent B. No esophageal erosion or pressure damage from proximal radial forces was seen with Stent C. On necropsy, swine 5 had a 0.5-cm periesophageal abscess. Histology revealed a localized inflammatory lesion at the esophageal exit site in swine 1, 3, and 9. The mucosectomy site was partially healed in three swine and poorly healed in six. All swine thrived clinically, except for a brief period of mild lethargy in swine 9 who improved with short-term antibiotic therapy. The submucosal tunnels were completely healed and no esophageal bleeding or stricture formation was observed. All swine survived 13.8 ± 0.4 days and gained weight in the postoperative period.

CONCLUSIONS

Esophageal stenting provides safe closure for NOTES thoracic procedures but may impede healing of the mucosectomy site.

Leaks and endoscopic assessment of break of integrity after NOTES gastrotomy: the LEAKING study, a prospective, randomized, controlled trial

BACKGROUND

Gastric leak testing after natural orifice transluminal endoscopic surgery (NOTES) gastrotomy closure may help reduce the risk of leaks after transgastric procedures.

OBJECTIVE

To develop a novel endoscopy-based system to determine the presence of a leak after NOTES gastrotomy and to compare this system prospectively with radiographic leak testing.

DESIGN

Prospective, randomized, controlled trial.

SETTING

Academic Medical Center laboratory.

SUBJECTS

Fifty swine.

INTERVENTION

During the pretrial phase, an endoscopic system for the measurement of intragastric pressure was developed. In the trial phase, swine with a NOTES gastrotomy were randomized to endoscopic versus radiographic leak testing. If a leak was demonstrated, the gastrotomy was reclosed by using a second-generation prototype T-anchor system. The primary outcome was leak detection after gastrotomy closure. The secondary outcome variables included necropsy findings, peritoneal fluid analysis, histologic examination, and clinical outcome.

RESULTS

Fourteen swine were included in the pretrial phase and 36 in the randomized trial. Swine were survived for a mean of 9 days postoperatively. Endoscopic pressure monitoring demonstrated a reproducible change in intragastric pressure with insufflation; r = 0.735, P = .001 and r = 0.769, P < or = .000 for the total and maximum pressures, respectively. Post-peritoneoscopy, there was a detectable and significant decrease in the mean total and mean maximum pressures versus baseline (P = .006 and P = .009). There was no significant difference between the radiologic and endoscopic arms in leak detection rate (4/18 vs 3/18, respectively, P = .500). Clinical outcomes and mean weight gain were equivalent. There was 1 operative abdominal wall injury and no deaths.

LIMITATIONS

Animal study.

CONCLUSION

Endoscopic pressure monitoring was reproducible, demonstrated the presence of gastric leak, and was as reliable as contrast-based radiographic leak testing.

NOTES transanal rectal cancer resection using transanal endoscopic microsurgery and laparoscopic assistance

BACKGROUND

The feasibility and safety of Natural Orifice Translumenal Endoscopic Surgery (NOTES) transanal endoscopic rectosigmoid resection using transanal endoscopic microsurgery (TEM) was previously demonstrated in human cadavers and a porcine survival model. We report the first clinical case of a NOTES transanal resection for rectal cancer using TEM and laparoscopic assistance, performed by a team of surgeons from Barcelona and Boston with extensive experience with NOTES and minimally invasive approaches to colorectal diseases.

METHODS

Transanal endoscopic rectal resection with total mesorectal excision using the TEM platform was performed in a 76-year-old woman with a T2N2 rectal cancer treated with preoperative chemoradiation. Laparoscopic visualization and assistance with retraction and exposure during rectosigmoid mobilization was provided through one 5-mm port, which was later used as the stoma site, and 2-mm needle ports, one of which was used as a drain site. The specimen was transected transanally followed by handsewn coloanal anastomosis.

RESULTS

The procedure was completed successfully with an operative time of 4 hours and 30 minutes. Mesorectal excision was complete. The postoperative course was uneventful, and the patient was discharged on the fourth postoperative day. The final pathology demonstrated pT1N0 with 23 negative lymph nodes and negative proximal, distal, and radial margins.

CONCLUSIONS

NOTES transanal endoscopic rectosigmoid resection using TEM and laparoscopic assistance is feasible and safe. Careful patient selection and improvement in NOTES instrumentation are critical to optimize this approach before widespread clinical application.

Survival study of natural orifice translumenal endoscopic surgery for rectosigmoid resection using transanal endoscopic microsurgery with or without transgastric endoscopic assistance in a swine model

BACKGROUND

The feasibility of transanal rectosigmoid resection with transanal endoscopic microsurgery (TEM) was previously demonstrated in a swine nonsurvival model in which transgastric endoscopic assistance also was shown to extend the length of colon mobilized transanally.

METHODS

A 2-week survival study evaluating transanal endoscopic rectosigmoid resection with stapled colorectal anastomosis was conducted with swine using the transanal approach alone (TEM group, n = 10) or a transanal approach combined with transgastric endoscopic assistance (TEM + TG group, n = 10). Gastrotomies were created using a needleknife and balloon dilation, then closed using prototype T-tags. Outcomes were evaluated and compared between the groups using Student's t-test and Fisher's exact test.

RESULTS

Relative to the TEM group, the average length of rectosigmoid mobilized in the TEM + TG group was 15.6 versus 10.5 cm (p < 0.0005), the length of the resected specimen was 9 versus 6.2 cm (p < 0.0005), and the mean operative time was 254.5 versus 97.5 min (p < 0.0005). Intraoperatively, no organ injury or major bleeding was noted. Two T-tag misfires occurred during gastrotomy closure and four small staple line defects requiring transanal repair including one in the TEM group and three in the TEM + TG group (p = 0.2). Postoperatively, there was no mortality, and the animals gained an average of 3.4 lb. Two major complications (10%) were identified at necropsy in the TEM + TG group including an intraabdominal abscess and an abdominal wall hematoma related to T-tag misfire. Gastrotomy closure sites and colorectal anastomoses were all grossly healed, with adhesions noted in 60 and 70% and microabscesses in 50 and 20% of the gastrotomy sites and colorectal anastomoses, respectively.

CONCLUSIONS

Natural orifice translumenal endoscopic surgery (NOTES) for rectosigmoid resection using TEM with or without transgastric endoscopic assistance is feasible and associated with low morbidity in a porcine survival model. Transgastric assistance significantly prolongs the operative time but extends the length of the rectosigmoid mobilized transanally, with a nonsignificant increase in complication rates related to gastrotomy creation.

New metastatic lymph node ratio system reduces stage migration in patients undergoing D1 lymphadenectomy for gastric adenocarcinoma

BACKGROUND

The American Joint Committee on Cancer (AJCC)/International Union Against Cancer (UICC) staging system for gastric cancer incorporates the absolute number of metastatic lymph nodes (N status) and is optimally used when >or=15 nodes are examined. The ratio of metastatic to examined nodes (N ratio) is an effective prognostic tool, but has not been examined in Western patients undergoing primarily D1 lymphadenectomy.

METHODS

Two hundred and fifty seven patients with gastric adenocarcinoma who underwent gastric resection between 1995 and 2005 at our institution were examined. Novel N ratio intervals were determined using the best cutoff approach (Nr0: N ratio = 0 and >or=15 nodes examined; Nr1: 0 <or= N ratio <or= 0.3; Nr2: 0.3 < N ratio <or= 0.7; and Nr3: N ratio > 0.7). Overall survival was examined according to N status and N ratio.

RESULTS

83% of patients underwent D1 lymphadenectomy with a median of 14 lymph nodes examined. Overall survival stratified by N status was significantly different in patients with <15 nodes examined compared with those with >or=15 nodes examined. When we stratified by N ratio intervals, there was no significant difference in overall survival in patients with <15 versus >or= 15 nodes examined. On multivariate analysis, N ratio but not N status was retained as an independent prognostic factor.

CONCLUSIONS

The use of N status for staging patients undergoing primarily D1 lymphadenectomy results in significant stage migration due to varying numbers of nodes examined. Use of N ratio reduces stage migration and may be a more reliable method of staging these patients.

Feasibility of endoscopic transesophageal thoracic sympathectomy (with video)

BACKGROUND

Thoracoscopic sympathectomy is the preferred surgical treatment for patients with disabling palmar hyperhidrosis. Current methods require a transthoracic approach to permit ablation of the thoracic sympathetic chain.

OBJECTIVE

To develop a minimally invasive, transesophageal endoscopic technique for a sympathectomy in a swine model.

DESIGN

Nonsurvival animal study.

SETTING

Animal trial at a tertiary care academic center.

SUBJECTS

This study involved 8 healthy Yorkshire swine.

INTERVENTIONS

After insertion of a double-channel gastroscope, a Duette Band mucosectomy device was used to create a small esophageal mucosal defect. A short, 5-cm submucosal tunnel was created by using the tip of the endoscope and biopsy forceps. Within the submucosal space, a needle-knife was used to incise the muscular esophageal wall and permit entry into the mediastinum and chest. The sympathetic chain was identified at the desired thoracic level and was ablated or transected. The animals were killed at the completion of the procedure.

MAIN OUTCOME MEASUREMENTS

Feasibility of endoscopic transesophageal thoracic sympathectomy.

RESULTS

The sympathetic chain was successfully ablated in 7 of 8 swine, as confirmed by gross surgical pathology and histology. In 1 swine, muscle fibers were inadvertently transected. On average, the procedure took 61.4+/-24.5 minutes to gain access to the chest, whereas the sympathectomy was performed in less than 3 minutes in all cases. One animal was killed immediately after sympathectomy, before the completion of the observation period, because of hemodynamic instability.

LIMITATIONS

Nonsurvival series, animal study.

CONCLUSIONS

Endoscopic transesophageal thoracic sympathectomy is technically feasible, simple, and can be performed in a porcine model.

Natural orifice versus conventional laparoscopic distal pancreatectomy in a porcine model: a randomized, controlled trial

BACKGROUND

Natural orifice transluminal endoscopic surgery (NOTES) research has primarily involved case series reports of low-risk procedures. Distal pancreatectomy has significant postoperative morbidity and would permit rigorous examination in a controlled trial setting.

OBJECTIVE

To compare endoscopic transgastric distal pancreatectomy (ETDP) and laparoscopic distal pancreatectomy (LDP).

DESIGN

Prospective, randomized, controlled trial.

SETTING

Academic hospital.

SUBJECTS

Forty-one swine, 28 block randomized.

INTERVENTIONS

LDP was performed with 3 trocars and stapled transection of the pancreas. ETDP was performed via a gastrotomy, with 1 trocar for visualization, by using endoloop placement, snare transection, and purse-string gastrotomy closure.

MAIN OUTCOME MEASUREMENTS

Clinical examination, CT, serum chemistries, necropsy, peritoneal fluid analysis, and histologic examination.

RESULTS

Swine were survived for 8 days. The procedure time for ETDP was significantly greater than for LDP (1:52 vs 0:33 [hours:minutes]; P = .00). Pancreatic specimen weight was similar (4.1 g vs 5.5 g; P = .108). Postoperatively, 26 of 28 animals thrived. In the LDP group, 1 death caused by pancreatic leak and renal failure occurred on day 1. In the ETDP group, 1 death caused by pneumothorax occurred intraoperatively. The necropsy, CT, and histologic examinations revealed focal resection-margin necrosis in 3 to 7 swine in the ETDP group with no proximal necrosis or pancreatitis. The groups were equivalent clinically, by survival, and by serum and peritoneal fluid analysis. The gastrotomy closure was associated with small serosal adhesions, but no gross abscess or necrosis.

LIMITATION

Animal study.

CONCLUSIONS

In the largest controlled trial of NOTES orifice surgery to date, there was no clinical or survival difference between NOTES and laparoscopic approaches.

Endoscopic interventions for weight loss surgery

In this paper we review the state-of-the-art in endoscopic interventions for obesity treatment and make best practice recommendations for weight loss surgery (WLS). We performed a systematic search of English-language literature published between April 2004 and June 2008 in MEDLINE and the Cochrane Library on WLS and endoscopic interventions, endoscopically placed devices, minimally invasive surgery, image-guided surgery, endoluminal surgery, endoscopic instrumentation, interventional gastroenterology, transluminal surgery, and natural orifice transluminal surgery. We also searched the literature on endoscopic interventions and WLS and patient safety. We identified 36 pertinent articles, all of which were reviewed in detail; assessed the current science in endoscopic interventions for WLS; and made best practice recommendations based on the latest available evidence. Our findings indicate that endoscopic interventions and endoscopically placed devices may provide valuable approaches to the management of WLS complications and the primary management of obesity. Given the rapid changes in endoscopic technologies and techniques, systematic literature review is required to address issues related to the emerging role of endoluminal surgery in the treatment of obesity. These interventions should be a high priority for development and investigation.