The Learning Curve for Robotic McKeown Esophagectomy in Patients With Esophageal Cancer

Effectiveness of Strategy-Focused Training in Colorectal Endoscopic Submucosal Dissection: A Retrospective Observational Study

BACKGROUND

Colorectal ESD, an advanced minimally invasive treatment, presents technical challenges, with globally varying training methods. We analyzed the learning curve of ESD training, emphasizing preoperative strategies, notably gravity traction, to guide ESD instructors and trainee programs.

METHOD

This retrospective study included 881 cases guided by an experienced supervisor. Six trainees received "strategy-focused" instruction. To evaluate the number of ESD experiences in steps, the following phases were classified based on ESD experiences of each trainees: Phase 0 (0-50 ESD), Phase 1 (51-100 ESD), Phase 2 (101-150 ESD), and Phase 3 (151-200 ESD). Lesion background, outcomes, and safety were compared across phases. Factors contributing to technical difficulty in early (Phase 0 and 1) and late phases (Phase 2 and 3) were identified, along with the utility of traction ESD with device assistance.

RESULT

Treatment outcomes were favorable, with 99.8% and 94.7% en bloc resection and curative resection rates, respectively. Approximately 90% self-completion rate could be achieved after experiencing about 50 cases (92.7% in Phase 1), signifying proficiency growth despite increased case difficulty. In early phases, factors such as left-sided colon, LST-NG morphology, and severe fibrosis pose challenges. In late phases, LST-NG morphology, mild and severe fibrosis remained significant. Traction-assisted ESD, utilized in 3% of cases, comprised planned (1.1%) and rescue (1.9%) methods. Planned traction aided specific lesions, while rescue traction was common in the right colon.

CONCLUSION

"Strategy-focused" ESD training consistently yields successful outcomes, effectively adapting to varying difficulty factors in different proficient stages.

Beyond the Square knot: A validation study for a novel knot-tying method named "inverse 9"

Purpose

We compared the "inverse 9" laparoscopic suturing and knot-tying (LSKT) method to the traditional LSKT method in a validation study to demonstrate the "inverse 9" method's superiority and effectiveness in laparoscopy.

Methods

On the basis of their experience in laparoscopic surgery, 78 trainees were divided into two groups, with 52 inexperienced trainees in group A and 26 experienced trainees in group B. In group A, 52 trainees were randomly allocated to either group A1 ("inverse 9" LSKT training) or group A2 (traditional LSKT training). In group B, experienced trainees were randomly assigned to receive "inverse 9" LSKT training (group B1) or continuing training in the traditional LSKT method (group B2). All trainees received the same instruction and assessment and were asked to provide a subjective assessment of the two training methods at the end of the training.

Results

The trainees in groups A1, A2, and B had similar average ages and were mostly male. After training, all showed preliminary mastery of LSKT (P < 0.05). The trainees in groups A1 and B1 achieved learning proficiency in the fifth assessment, while those in group A2 achieved it in the sixth assessment. The trainees in groups A1 and B1 showed lower difficulty in achieving mastery and lower operation fatigue scores (P < 0.05), and 61.50 % of the trainees in group B preferred the "inverse 9" method in subjective evaluation.

Conclusion

As a novel LSKT technique, "inverse 9" offers a multitude of benefits. In addition to ensuring a simpler operation and effectively reducing the knot-tying time, it also involves a shorter learning curve than traditional LSKT methods. As such, it can be easily mastered and widely adopted as a standard LSKT technique.

Exploring the learning curve in minimally invasive esophagectomy: a systematic review

Minimally invasive esophagectomy (MIE) has been shown to be superior to open esophagectomy with reduced morbidity, mortality, and comparable lymph node (LN) harvest. However, MIE is technically challenging. This study aims to perform a pooled analysis on the number of cases required to surmount the learning curve (LC), i.e. NLC in MIE. PubMed, Embase, Scopus, and the Cochrane Library were systematically searched for articles from inception to June 2022. Inclusion criteria were articles that reported LC in video-assisted MIE (VAMIE) and/or robot-assisted MIE (RAMIE). Poisson means (95% confidence interval [CI]) was used to determine NLC. Negative binomial regression was used for comparative analysis. There were 41 articles with 45 data sets (n = 7755 patients). The majority of tumors were located in the lower esophagus or gastroesophageal junction (66.7%, n = 3962/5939). The majority of data sets on VAMIE (n = 16/26, 61.5%) used arbitrary analysis, while the majority of data sets (n = 14/19, 73.7%) on RAMIE used cumulative sum control chart analysis. The most common outcomes reported were overall operating time (n = 30/45) and anastomotic leak (n = 28/45). Twenty-four data sets (53.3%) reported on LN harvest. The overall NLC was 34.6 (95% CI: 30.4-39.2), 68.5 (95% CI: 64.9-72.4), 27.5 (95% CI: 24.3-30.9), and 35.9 (95% CI: 32.1-40.2) for hybrid VAMIE, total VAMIE, hybrid RAMIE, and total RAMIE, respectively. NLC was significantly lower for total RAMIE compared to total VAMIE (incidence rate ratio: 0.52, P = 0.032). Studies reporting NLC in MIE are heterogeneous. Further studies should clearly define prior surgical experiences and assess long-term oncological outcomes using non-arbitrary analysis.

Deep learning-based recognition of key anatomical structures during robot-assisted minimally invasive esophagectomy

OBJECTIVE

To develop a deep learning algorithm for anatomy recognition in thoracoscopic video frames from robot-assisted minimally invasive esophagectomy (RAMIE) procedures using deep learning.

BACKGROUND

RAMIE is a complex operation with substantial perioperative morbidity and a considerable learning curve. Automatic anatomy recognition may improve surgical orientation and recognition of anatomical structures and might contribute to reducing morbidity or learning curves. Studies regarding anatomy recognition in complex surgical procedures are currently lacking.

METHODS

Eighty-three videos of consecutive RAMIE procedures between 2018 and 2022 were retrospectively collected at University Medical Center Utrecht. A surgical PhD candidate and an expert surgeon annotated the azygos vein and vena cava, aorta, and right lung on 1050 thoracoscopic frames. 850 frames were used for training of a convolutional neural network (CNN) to segment the anatomical structures. The remaining 200 frames of the dataset were used for testing the CNN. The Dice and 95% Hausdorff distance (95HD) were calculated to assess algorithm accuracy.

RESULTS

The median Dice of the algorithm was 0.79 (IQR = 0.20) for segmentation of the azygos vein and/or vena cava. A median Dice coefficient of 0.74 (IQR = 0.86) and 0.89 (IQR = 0.30) were obtained for segmentation of the aorta and lung, respectively. Inference time was 0.026 s (39 Hz). The prediction of the deep learning algorithm was compared with the expert surgeon annotations, showing an accuracy measured in median Dice of 0.70 (IQR = 0.19), 0.88 (IQR = 0.07), and 0.90 (0.10) for the vena cava and/or azygos vein, aorta, and lung, respectively.

CONCLUSION

This study shows that deep learning-based semantic segmentation has potential for anatomy recognition in RAMIE video frames. The inference time of the algorithm facilitated real-time anatomy recognition. Clinical applicability should be assessed in prospective clinical studies.

Hybrid laparoscopic versus fully robot-assisted minimally invasive esophagectomy: an international propensity-score matched analysis of perioperative outcome

BACKGROUND

Currently, little is known regarding the optimal technique for the abdominal phase of RAMIE. The aim of this study was to investigate the outcome of robot-assisted minimally invasive esophagectomy (RAMIE) in both the abdominal and thoracic phase (full RAMIE) compared to laparoscopy during the abdominal phase (hybrid laparoscopic RAMIE).

METHODS

This retrospective propensity-score matched analysis of the International Upper Gastrointestinal International Robotic Association (UGIRA) database included 807 RAMIE procedures with intrathoracic anastomosis between 2017 and 2021 from 23 centers.

RESULTS

After propensity-score matching, 296 hybrid laparoscopic RAMIE patients were compared to 296 full RAMIE patients. Both groups were equal regarding intraoperative blood loss (median 200 ml versus 197 ml, p = 0.6967), operational time (mean 430.3 min versus 417.7 min, p = 0.1032), conversion rate during abdominal phase (2.4% versus 1.7%, p = 0.560), radical resection (R0) rate (95.6% versus 96.3%, p = 0.8526) and total lymph node yield (mean 30.4 versus 29.5, p = 0.3834). The hybrid laparoscopic RAMIE group showed higher rates of anastomotic leakage (28.0% versus 16.6%, p = 0.001) and Clavien Dindo grade 3a or higher (45.3% versus 26.0%, p < 0.001). The length of stay on intensive care unit (median 3 days versus 2 days, p = 0.0005) and in-hospital (median 15 days versus 12 days, p < 0.0001) were longer for the hybrid laparoscopic RAMIE group.

CONCLUSIONS

Hybrid laparoscopic RAMIE and full RAMIE were oncologically equivalent with a potential decrease of postoperative complications and shorter (intensive care) stay after full RAMIE.

Learning curve for adoption of robot-assisted minimally invasive esophagectomy: a systematic review of oncological, clinical, and efficiency outcomes

BACKGROUND

Robot-assisted minimally invasive esophagectomy (RAMIE) is gaining increasing popularity as an operative approach. Learning curves to achieve surgical competency in robotic-assisted techniques have shown significant variation in learning curve lengths and outcomes. This study aimed to summarize the current literature on learning curves for RAMIE.

METHODS

A systematic review was conducted in line with PRISMA guidelines. Electronic databases PubMed, MEDLINE, and Cochrane Library were searched, and articles reporting on learning curves in RAMIE were identified and scrutinized. Studies were eligible if they reported changes in operative outcomes over time, or learning curves, for surgeons newly adopting RAMIE.

RESULTS

Fifteen studies reporting on 1767 patients were included. Nine studies reported on surgeons with prior experience of robot-assisted surgery prior to adopting RAMIE, with only four studies outlining a specified RAMIE adoption pathway. Learning curves were most commonly analyzed using cumulative sum control chart (CUSUM) and were typically reported for lymph node yields and operative times, with significant variation in learning curve lengths (18-73 cases and 20-80 cases, respectively). Most studies reported adoption without significant impact on clinical outcomes such as anastomotic leak; significant learning curves were more likely in studies, which did not report a formal learning or adoption pathway.

CONCLUSION

Reported RAMIE adoption phases are variable, with some authors suggesting significant impact to patients. With robust training through formal programmes or proctorship, however, others report RAMIE adoption without impact on clinical outcomes. A formalized adoption curriculum appears critical to prevent adverse effects on operative efficiency and patient care.

Learning Curve of Robot-Assisted Lymph Node Dissection of the Left Recurrent Laryngeal Nerve: A Retrospective Study of 417 Patients

OBJECTIVE

Left recurrent laryngeal nerve (no.106recL) lymph node dissection is a challenging procedure, and robotic-assisted minimally invasive esophagectomy (RAMIE) may have some advantages. This study aimed to determine the learning curve of no.106recL lymph node dissection.

METHODS

The data of 417 patients who underwent McKeown RAMIE between June 2017 and June 2022 were retrospectively analyzed. The lymph node harvest of no.106recL was used to determine the learning curve, and the cumulative sum (CUSUM) method was employed to obtain the inflection point.

RESULTS

A total of 404 patients (404/417, 96.9%) underwent robotic surgery. Based on the number of no.106recL lymph nodes harvested, the CUSUM learning curve was mapped and divided into three phases: phase I (1‒75 cases), phase II (76‒240 cases), and phase III (241‒404 cases). The median (IQR) number of no.106recL lymph node harvests were 1 (4), 3 (6,) and 4 (4) in each phase (p < 0.001). The lymph node dissection rate gradually increased from 62.7% in phase I to 82.9% in phase III (p = 0.001). The total and thoracic lymph node harvest gradually increased (p < 0.001), whereas operation time (p = 0.001) and blood loss gradually decreased (p < 0.001). Moreover, the incidence of total complication (p = 0.020) and recurrent laryngeal nerve injury (p = 0.001) significantly decreased, and the postoperative hospital stay gradually shortened (p < 0.001).

CONCLUSION

Robotic no.106recL lymph node dissection has some advantages for patients with esophageal cancer. In this study, perioperative and clinical outcomes were significantly improved over the learning curve. However, further prospective studies are required to confirm our results.

Robotic Esophagectomy Trends and Early Surgical Outcomes: The US Experience

BACKGROUND

Recent esophagectomy trends were evaluated to describe the shift in surgical approach and outcomes using The Society of Thoracic Surgeons General Thoracic Surgery Database.

METHODS

All patients who underwent an esophagectomy with gastric conduit from 2015 to 2019 were identified and analyzed according to original intended approach. After performing volume trend analysis of patients, operative outcomes were evaluated.

RESULTS

Among 10,607 patients, esophagectomy was open in 5763 (54.3%), minimally invasive (MIE) in 3524 (33.2%), and robotic (RAMIE) in 1320 (12.4%). Within 5 years, MIE and RAMIE combined rose to majority approach (open from 58% to 42% of annual volume). While MIE and RAMIE were associated with higher rates of anastomotic leak, loss of conduit, pulmonary embolus, and reoperation, R0 resection and harvested number of lymph nodes exceeded those in open approaches. Operative mortality did not differ by approach (3.21% open vs 2.72% MIE vs 2.50% RAMIE; P = .2329). On multivariable analysis, RAMIE was independently associated with higher rate of anastomotic leak compared to open (adjusted odds ratio 1.53, 95% CI 1.14-2.04), while both MIE and RAMIE had lower mean length of stay. Propensity matching of 1320 pairs found a higher risk of anastomotic leak requiring surgery for RAMIE compared with MIE (adjusted odds ratio 1.39, 95% CI 1.01-1.92).

CONCLUSIONS

In less than a decade, the dominant surgical approach in The Society of Thoracic Surgeons General Thoracic Surgery Database has become minimally invasive (RAMIE and MIE). While anastomotic leak and reoperation, more common in RAMIE, require a technical solution, these complications have not raised operative mortality. Further studies are needed to address long-term results and oncologic outcome.

Perioperative Outcomes and Learning Curve of Robot-Assisted McKeown Esophagectomy

BACKGROUND

This study aimed to evaluate the perioperative outcomes of patients undergoing robot-assisted McKeown esophagectomy (RAME) and the learning curves of surgeons performing RAME at a single center.

METHODS

Perioperative outcomes of RAME and video-assisted McKeown esophagectomy (VAME) were compared after eliminating confounding factors by propensity score matching (PSM). The cumulative sum (CUSUM) method was used to evaluate the learning curves of RAME for a single surgical team.

RESULTS

In general, a total of 198 patients with esophageal cancer (RAME: 45 patients, VAME: 153 patients) were included in this study, and 43 pairs of patients receiving RAME or VAME were matched using 1:1 PSM analysis. Those in the RAME group had more lymph nodes dissected in the total lymph nodes (median 29.0 vs. 26.0, P = 0.011) and the upper mediastinum (median 8.0 vs. 6.0, P < 0.001), especially the left recurrent laryngeal nerve (RLN) lymph node (median 4.0 vs. 2.0, P = 0.001). According to the trend of the CUSUM plot, the learning curve was divided into two stages at the 20th RAME procedure. After mastering the learning curve, RAME harvested a significantly higher number of upper mediastinal lymph nodes (median 9.0 vs. 6.0, P = 0.001), left RLN lymph nodes (median 5.0 vs. 3.5, P = 0.003), and right RLN lymph nodes (median 4.0 vs. 2.0, P = 0.002). Meanwhile, the incidence of postoperative pneumonia in the proficiency phase was significantly lower than that in the learning phase (4.0% vs. 25.0%, P = 0.04).

CONCLUSIONS

RAME improved left RLN lymph node dissection. Surgeons with extensive VAME experience need at least 20 cases to achieve early proficiency in RAME.

Initial Learning Curve and Stereotypical Use of Extra Arm During da Vinci Chest Procedures of McKeown Esophagectomy

Objective: McKeown esophagectomy facilitates extensive lymphadenectomy for the optimal management of esophageal cancer. Robot-assisted esophagectomy (RAE) was introduced in an attempt to reduce the incidence of postoperative complications. The da Vinci System has 3 active robotic arms in addition to the camera scope, and an extra robotic arm (ERA) is generally used to maintain a fine and stable operative field. However, the optimal use of an ERA has not been documented. In addition, the learning curve of the RAE using the da Vinci System remains controversial. In this study, we aimed to determine the optimal use of an ERA in association with the initial learning curve of robotic McKeown esophagectomy with extremely extensive lymphadenectomy. Methods: We reviewed 81 consecutive patients who underwent RAE. To determine whether stereotypical use of an ERA after establishment of its optimal use accounted for the learning curve, we measured the duration of 14 steps and the duration when performed with optimal use of an ERA in the corresponding step by reviewing video-recorded procedures. We then calculated the ratio as the degree of stereotypical use of the ERA during the da Vinci chest procedures. Results: The cumulative sum method showed that the learning curve required 27 cases of RAE. In addition, stereotypical use of the ERA was significantly associated with the learning curve of RAE. Conclusions: Establishment of optimal use of an ERA could help to accelerate the learning curve in da Vinci chest procedures during McKeown esophagectomy with extensive lymphadenectomy.

Clinical Effect and Postoperative Pain of Laparo-Thoracoscopic Esophagectomy in Patients with Esophageal Cancer

Objective

To investigate the clinical effect and postoperative pain of laparo-thoracoscopic esophagectomy in patients with esophageal cancer.

Methods

A total of 90 patients with esophageal cancer who were admitted and treated in our hospital from August 2020 to November 2021 were randomly selected as the research subjects for prospective analysis, and the patients were assigned to the control group and the experimental group according to the time of admission equally, with 45 cases in each group. Patients in the control group underwent conventional open surgery, and those in the experimental group underwent laparo-thoracoscopic esophagectomy. Then, operation-related indicators, postoperative pain, inflammatory factors, and complications were compared between the two groups.

Results

The operation time, intraoperative blood loss, postoperative drainage, and postoperative length of stays of the experimental group were significantly shorter or less than those of the control group (P < 0.05); there was no significant difference in the number of lymph nodes dissected between the two groups (P > 0.05). The number of patients with moderate and severe pain in the experimental group was significantly smaller than that in the control group, and the number of patients with mild pain was significantly larger than that in the control group (P < 0.05). The level of inflammatory factors (TNF-α, IL-6, IL-8, and IL-10) was significantly lower than that in the control group (P < 0.05); the incidence of surgical complications in the experimental group was significantly lower than that in the control group (P < 0.05).

Conclusion

Laparo-thoracoscopic esophagectomy can significantly improve the clinical effect in patients with esophageal cancer. Thoracic-laparoscopic esophagectomy can significantly improve the clinical results of patients with esophageal cancer. With better performance in surgery-related indicators, lower inflammatory factor levels and postoperative pain, and fewer postoperative complications, it will speed up patients' recovery and is worthy of clinical promotion and application.

Short-term outcomes of robot-assisted minimally invasive esophagectomy with extended lymphadenectomy for esophageal cancer compared with video-assisted minimally invasive esophagectomy: A single-center retrospective study

BACKGROUND

The safety and feasibility of robot-assisted minimally invasive esophagectomy (RAMIE) remain unclear. The aim of this study was to compare the short-term outcomes of RAMIE with extended lymphadenectomy and conventional minimally invasive esophagectomy (MIE) in order to investigate the safety and feasibility of RAMIE.

METHODS

A retrospective analysis of 87 patients who underwent minimally invasive esophagectomy at our institution between April 2018 and March 2020 was made, assigning 22 in the RAMIE group and 65 in the MIE group. Short-term clinical outcomes and clinical baseline data were compared.

RESULTS

The baseline characteristics were comparable. No significant difference in median thoracic phase blood loss and median number of dissected mediastinal lymph nodes were observed. The median operative time of thoracic approach was significantly longer in the RAMIE group than the MIE group (305 minutes [221-397] vs 227 minutes [133-365], P < .0001). With respect to postoperative complications such as recurrent laryngeal nerve paralysis (Clavien-Dindo ≥ grade II) (RAMIE 4.6% vs MIE 17%, P = .11) and postoperative pneumonia (Clavien-Dindo ≥ grade III) (RAMIE 9% vs MIE 23%, P = .13), no significant difference was observed. The patients in the RAMIE group had a better postoperative swallowing function (P = .023) and were able to start oral food intake significantly earlier (P = .007). The median hospital stay was significantly shorter in the RAMIE group than in the MIE (23 days vs 35 days, P = .009).

CONCLUSIONS

RAMIE with extended lymphadenectomy was safe and feasible for esophageal cancer and resulted in improved postoperative swallowing function and shorter postoperative hospital stay.

Double-Docking Technique, an Optimized Process for Intrathoracic Esophagogastrostomy in Robot-Assisted Ivor Lewis Esophagectomy

Background

Though robotic Ivor Lewis esophagectomy has been increasingly applied, intrathoracic esophagogastrostomy is still a technical barrier. In this retrospective study, we introduced a double-docking technique for intrathoracic esophagogastrostomy to optimize surgical exposure and facilitate intrathoracic anastomosis. Moreover, we compared the clinical outcomes between the double-docking technique and anastomosis with a single-docking procedure in robotic Ivor Lewis esophagectomy.

Methods

From March 2017 to September 2020, the clinical data of 68 patients who underwent robotic Ivor Lewis esophagectomy were reviewed, including 23 patients who underwent the double-docking technique (double-docking group) and 45 patients who underwent single-docking robotic esophagectomy (single-docking group). All patients were diagnosed with esophageal cancer or gastro-esophageal junction by biopsy before surgery. The technical details of the double-docking technique are described in this article.

Results

There was no difference in the patient demographics data between the two groups. The median surgical time in the double-docking group was slightly shorter than in the classic group without statistical difference (380 vs. 395 min, p = 0.368). In the double-docking group, the median blood loss was 90 mL, the median number of lymph nodes harvested was 17, and the R0 resection rates were 100% (23/23). There were no differences in the surgical outcomes between the two groups.

Conclusions

Based on our experience, the double-docking technique provides good surgical exposure when fashioning anastomosis, and such a technique does not increase the surgical time. Therefore, we believe that the double-docking technique is a safe and effective method for intrathoracic esophagogastrostomy while providing good exposure and ensuring the convenience and reliability of intrathoracic anastomosis.

Impact of prior thoracoscopic experience on the learning curve of robotic McKeown esophagectomy: a multidimensional analysis

PURPOSE

Left upper mediastinal lymph node dissection (UMLND)-a technically demanding step of McKeown esophagectomy-is frequently complicated by recurrent laryngeal nerve (RLN) palsy. Under the hypothesis that robotic esophagectomy (RE) could increase the safety and feasibility of UMLND, we retrospectively investigated the degree to which a pre-existing experience in video-assisted thoracoscopic esophagectomy (VATE) may affect the learning curves of this critical part of RE.

METHODS

Surgeon A had previously performed > 150 VATE procedures before transitioning to RE. While surgeon B had previously assisted to 50 RE, his pre-existing VATE experience consisted of less than five procedures. A total of 103 and 76 McKeown RE procedures were performed by surgeons A and B, respectively. The learning curve of left UMLND for each surgeon was examined using the cumulative sum method.

RESULTS

The inflection point of RLN palsy for surgeon A occurred at patient 31. While the nerve palsy rate decreased from 32.3 to 4.2% (p < 0.001), the number of nodes harvested during left UMLND did not appreciably change. Surgeon B showed a bimodal learning curve for RLN palsy with primary and secondary inflection points at patients 15 and 49, respectively. The RLN palsy rate initially decreased from 66.7% (patients 1-15) to 14.7% (patients 16-49), followed by an additional decline to 3.7% (patients 50-76). However, the number of nodes harvested during left UMLND showed a downtrend which was paralleled by decreasing rates of RLN palsy. These results indicate that surgeon B has not yet reached an ideal balance between an extensive UMLND and nerve protection.

CONCLUSION

The pre-existing VATE experience seems to affect the learning curves of left UMLND during RE.

INFLUENCE OF MINIMALLY INVASIVE LAPAROSCOPIC EXPERIENCE SKILLS ON ROBOTIC SURGERY DEXTERITY

Background:

It is unclear if there is a natural transition from laparoscopic to robotic surgery with transfer of abilities.

Aim:

To measure the performance and learning of basic robotic tasks in a simulator of individuals with different surgical background.

Methods:

Three groups were tested for robotic dexterity: a) experts in laparoscopic surgery (n=6); b) experts in open surgery (n=6); and c) non-medical subjects (n=4). All individuals were aged between 40-50 years. Five repetitions of four different simulated tasks were performed: spatial vision, bimanual coordination, hand-foot-eye coordination and motor skill.

Results:

Experts in laparoscopic surgery performed similar to non-medical individuals and better than experts in open surgery in three out of four tasks. All groups improved performance with repetition.

Conclusion:

Experts in laparoscopic surgery performed better than other groups but almost equally to non-medical individuals. Experts in open surgery had worst results. All groups improved performance with repetition.

Evaluation of the learning curve for robot-assisted rectal surgery using the cumulative sum method

BACKGROUND

There is no clear evidence on the number of cases required to master the techniques required in robot-assisted surgery for different surgical fields and techniques. The purpose of this study was to clarify the learning curve of robot-assisted rectal surgery for malignant disease by surgical process.

METHOD

The study retrospectively analyzed robot-assisted rectal surgeries performed between April 2014 and July 2020 for which the operating time per process was measurable. The following learning curves were created using the cumulative sum (CUSUM) method: (1) console time required for total mesorectal excision (CUSUM tTME), (2) time from peritoneal incision to inferior mesenteric artery dissection (CUSUM tIMA), (3) time required to mobilize the descending and sigmoid colon (CUSUM tCM), and (4) time required to mobilize the rectum (CUSUM tRM). Each learning curve was classified into phases 1-3 and evaluated. A fifth learning curve was evaluated for robot-assisted lateral lymph node dissection (CUSUM tLLND).

RESULTS

This study included 149 cases. Phase 1 consisted of 32 cases for CUSUM tTME, 30 for CUSUM tIMA, 21 for CUSUM tCM, and 30 for CUSUM tRM; the respective numbers were 54, 48, 45, and 61 in phase 2 and 63, 71, 83, and 58 in phase 3. There was no significant difference in the number of cases in each phase. Lateral lymph node dissection was initiated in the 76th case where robot-assisted rectal surgery was performed. For CUSUM tLLND, there were 12 cases in phase 1, 6 in phase 2, and 7 cases in phase 3.

CONCLUSIONS

These findings suggest that the learning curve for robot-assisted rectal surgery is the same for all surgical processes. Surgeons who already have adequate experience in robot-assisted surgery may be able to acquire stable technique in a smaller number of cases when they start to learn other techniques.

Surgical outcomes after totally minimally invasive Ivor Lewis esophagectomy. A systematic review and meta-analysis

BACKGROUND

A transthoracic esophagectomy is associated with high rates of morbidity. Minimally invasive esophagectomy has emerged to decrease such morbidity. The aim of this study was to accurately determine surgical outcomes after totally minimally invasive Ivor-Lewis Esophagectomy (TMIE).

METHODS

A systematic literature search was performed to identify original articles analyzing patients who underwent TMIE. Main outcomes included overall morbidity, major morbidity, pneumonia, arrhythmia, anastomotic leak, chyle leak, and mortality. A meta-analysis was conducted to estimate the overall weighted proportion and its 95% confidence interval (CI) for each analyzed outcome.

RESULTS

A total of 5619 patients were included for analysis; 4781 (85.1%) underwent a laparoscopic/thoracoscopic esophagectomy and 838 (14.9%) a robotic-assisted esophagectomy. Mean age of patients was 63.5 (55-67) years and 75.8% were male. Overall morbidity and major morbidity rates were 39% (95% CI, 33%-45%) and 20% (95% CI, 13%-28%), respectively. Postoperative pneumonia and arrhythmia rates were 10% (95% CI, 8%-13%) and 12% (95% CI, 8%-17%), respectively. Anastomotic leak rate across studies was 8% (95% CI, 6%-10%). Chyle leak rate was 3% (95% CI, 2%-5%). Mortality rate was 2% (95% CI, 2%-2%). Median ICU stay and length of hospital stay were 2 (1-4) and 11.2 (7-20) days, respectively.

CONCLUSIONS

Totally minimally invasive Ivor-Lewis esophagectomy is a challenging procedure with high morbidity rates. Strategies to enhance postoperative outcomes after this operation are still needed.

Learning curves in minimally invasive esophagectomy: A systematic review and evaluation of benchmarking parameters

BACKGROUND

Minimally invasive techniques are increasingly used in the treatment of esophageal cancer. The learning curve for minimally invasive esophagectomy is variable and can impact patient outcomes. The aim of this study was to review the current evidence on learning curves in minimally invasive esophagectomy and identify which parameters are used for benchmarking.

METHODS

A search of the major reference databases (PubMed, Medline, Cochrane) was performed with no time limits up to February 2020. Results were screened in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were included if an assessment of the learning curve was reported on, regardless of which (if any) statistical method was used.

RESULTS

Twenty-nine studies comprising 3,741 patients were included. Twenty-two studies reported on a combination of thoracoscopic, hybrid, and total minimally invasive esophagectomy, 6 studies reported robotic-assisted minimally invasive esophagectomy alone, and 1 study evaluated both robotic-assisted minimally invasive esophagectomy and thoracoscopic esophagectomies. Operating time was the most frequently used parameter to determine learning curve progression (23/39 studies), with number of resected lymph nodes, morbidity, and blood loss also frequently used. Learning curves were found to plateau at 7 to 60 cases for thoracoscopic esophagectomy, 12 to 175 cases for total and thoracoscopic/hybrid esophagectomy, and 9 to 85 cases for robotic-assisted minimally invasive esophagectomy.

CONCLUSION

Multiple parameters are employed to gauge minimally invasive esophagectomy learning curve progression. However, there are no validated or approved sets of outcomes. Further work is required to determine the optimum parameters that should be used to ensure best patient outcomes and required length of proctoring.

Pretreatment-assisted robot intrathoracic layered anastomosis: our exploration in Ivor-Lewis esophagectomy

Background

Minimal invasive Ivor-Lewis esophagectomy (MIIVE) with intrathoracic esophago-gastric anastomosis (EGA) is still under exploration and the preferred technique for intrathoracic anastomosis has not been established.

Methods

We retrospectively reviewed 43 consecutive patients who underwent MIIVE using the series technique called pretreatment-assisted robot intrathoracic layered anastomosis (PRILA), performed by a single surgeon between September 2018 and December 2020. The operative outcomes were analyzed.

Results

The mean total operation time had been reduced from 446.38±54.775 minutes (range, 354-552) in the first year to 347.70±60.420 minutes (range, 249-450) later. There were no conversions to thoracotomy. All the patients achieved R0 resection. No patient suffered from anastomotic leakage. There was no 30-day mortality. The median length of postoperative stay was 10.0 days.

Conclusions

PRILA further visualizes and streamlines the process of minimal invasive intrathoracic EGA, thus ensuring the precise anastomosis. It could be considered as a feasible alternative for intrathoracic EGA in MIILE.

From McKeown to Ivor Lewis, the learning curve for thoracic lymphadenectomy over the first 100 robotic esophagectomy cases: a retrospective study

Background

Lymphadenectomy is an essential but challenging part of the surgical treatment for esophageal cancer. However, the previously reported learning curve for robotic esophagectomy primarily focused on only one surgical approach (McKeown or Ivor Lewis). However, both approaches must be mastered by a mature robotic surgical team to deal with different clinical conditions and satisfy patients' needs. This study aimed to show how an experienced esophageal surgical team became proficient in both McKeown and Ivor Lewis robotic esophagectomy.

Methods

A retrospective review of the first 100 cases of robot-assisted minimally invasive esophagectomy (RAMIE) by a single surgical team was performed. The cumulative sum (CUSUM) analysis was used to distinguish the change point during the learning course. A subgroup analysis was performed according to a surgical approach (McKeown or Ivor Lewis) to determine the effect of experience from one surgical approach on learning the other RAMIE technique.

Results

According to the tendency of the CUSUM plot, the learning curve was divided into four phases. The subgroup analysis indicated the decline of the CUSUM plot in the 3rd phase originated from the start of the Ivor Lewis approach. The attending surgeon took 23 cases to achieve a significant improvement in the number of harvested thoracic lymph nodes using the McKeown approach. Regardless of the acquired experience of McKeown RAMIE, it took another 18 cases for the surgical team to achieve significant improvement in harvesting thoracic lymph nodes using the Ivor Lewis approach.

Conclusions

Twenty-three cases were needed for an experienced surgical team to improve thoracic lymphadenectomy results using McKeown RAMIE. There was another learning phase during the transition from McKeown to Ivor Lewis esophagectomy. Importantly, the acquired experience from performing McKeown RAMIE could shorten how long it takes to learn Ivor Lewis RAMIE.

Does Timing of Robotic Esophagectomy Adoption Impact Short-Term Postoperative Outcomes?

BACKGROUND

Robotic esophagectomies are increasingly common and are reported to have superior outcomes compared with an open approach; however, it is unclear if all institutions can achieve such outcomes. We hypothesize that early adopters of robotic technique would have improved short-term outcomes.

METHODS

The National Cancer Database (2010-2016) was used to identify robotic esophagectomies. Early adopters were defined as programs which performed robotic esophagectomies in 2010-2011, late adopters in 2012-2013. Outcomes of esophagectomies performed between 2014 and 2016 were compared and included length of stay, number of lymph nodes evaluated, readmission, conversion rate, and 90-day mortality. Multivariable regressions, accounting for robotic esophagectomy volume, were used to control for confounding factors.

RESULTS

There were 37 early adopters and 35 late adopters. Between 2014 and 2016, 683 robotic esophagectomies were performed: 446 (65.3%) by early adopters and 237 (34.7%) by late adopters. Early adopters were more likely to be academic programs (96.2 versus 72.8%, P < 0.01). Other clinical and demographic variables were similar. Late adopters were found to have decreased a number of lymph nodes evaluated (coefficient -2.407, P = 0.004) compared with early adopters. There were no significant differences in length of stay, readmissions, rate of positive margins, conversion from robotic to open, or 90-day mortality.

CONCLUSIONS

When accounting for robotic esophagectomy volume, late adoption of robotic esophagectomy was associated with a reduced lymph node harvest, but other postoperative outcomes were similar. These data suggest that programs can safely start new robotic esophagectomy programs, but must ensure an adequate case load.

A structured training pathway to implement robot-assisted minimally invasive esophagectomy: the learning curve results from a high-volume center

To ensure safe implementation of robot-assisted minimally invasive esophagectomy (RAMIE), the learning process should be optimized. This study aimed to report the results of a surgeon who implemented RAMIE in a German high-volume center by following a tailored and structured training pathway that involved proctoring. Consecutive patients who underwent RAMIE during the course of the program were included from a prospective database. A single surgeon, who had prior experience in conventional MIE, performed all RAMIE procedures. Cumulative sum (CUSUM) learning curves were plotted for the thoracic operating time and intraoperative blood loss. Perioperative outcomes were compared between patients who underwent surgery before and after a learning curve plateau occurred. Between 2017 and 2018, the adopting center adhered to the structured training pathway, and a total of 70 patients were included in the analysis. The CUSUM learning curves showed plateaus after 22 cases. In consecutive cases 23 to 70, the operating time was shorter for both the thoracic phase (median 215 vs. 249 minutes, P = 0.001) and overall procedure (median 394 vs. 440 minutes, P = 0.005), intraoperative blood loss was less (median 210 vs. 400 milliliters, P = 0.029), and lymph node yield was higher (median 32 vs. 23 nodes, P = 0.001) when compared to cases 1 to 22. No significant differences were found in terms of conversion rates, postoperative complications, length of stay, completeness of resection, or mortality. In conclusion, the structured training pathway resulted in a short and safe learning curve for RAMIE in this single center's experience. As the pathway seems effective in implementing RAMIE without compromising the early oncological outcomes and complication rates, it is advised for surgeons who are wanting to adopt this technique.

A standardized approach for the thoracic dissection in robotic-assisted minimally invasive esophagectomy (RAMIE)

Robot-assisted minimally invasive esophagectomy (RAMIE) is increasingly being adopted as the preferred surgical treatment for esophageal cancer, as it is superior to open esophagectomy and a good alternative to conventional minimally invasive esophagectomy. This paper addresses the technical details of the thoracoscopic phase of RAMIE, including the operating room set-up, patient positioning, port placement, and surgical steps.

Specific complications and limitations of robotic esophagectomy

Regardless of the approach to esophagectomy, it is an operation that may be associated with significant risk to the patient. Robotic-assisted minimally invasive esophagectomy (RAMIE) has the same potential for short- and long-term complications as does open and minimally invasive esophagectomy. These complications include among others, the risk for anastomotic leak, gastric tip necrosis, vocal cord palsy, and chylothorax. Moreover, there are additional risks that are unique to the robotic platform such as hardware or software malfunction. These risks are heavily influenced by numerous factors including the patient's comorbidities, whether neoadjuvant therapy was administered, and the extent of the surgical team's experience. The limitations of RAMIE are therefore based on the careful assessment of the patient for operability, the tumor for resectability and the team for surgical ability. This article will tackle the topic of complications and limitations of RAMIE by examining each of these issues. It will also describe the recommended terminology for reporting post-esophagectomy complications.

Lymph node dissection around left recurrent laryngeal nerve: robot-assisted vs. video-assisted McKeown esophagectomy for esophageal squamous cell carcinoma

OBJECTIVE

This study investigated the advantages of robot-assisted McKeown esophagectomy (RAME) for extensive superior mediastinal lymph node dissection (LND) versus video-assisted McKeown esophagectomy (VAME).

METHODS

The cases of 184 consecutive esophageal squamous cell carcinoma (ESCC) patients who underwent minimally invasive McKeown esophagectomy (109 with RAME, 75 with VAME) performed by a single surgical group between June 2017 and December 2019 were retrospectively reviewed.

RESULTS

Overall, 59.8% (110/181) patients (70 treated with RAME, 40 treated with VAME; 64.2% vs. 53.3%, respectively, p = 0.139) underwent complete LND around the left recurrent laryngeal nerve (RLN) by pathological assessment. Cumulative sum plots showed increased numbers of LND around the left RLN (3.6 ± 2.0 vs. 5.4 ± 2.7, p = 0.008) and a decreased incidence of recurrent nerve injury (27.9% vs. 7.4%, p = 0.037) after RAME learning curve. Despite similar overall LND results (30.6 ± 10.2 vs. 28.1 ± 10.2, p > 0.05), RAME yielded more LND (5.4 ± 2.7 vs. 4.4 ± 2.2, p = 0.016) and a greater proportion of lymph node metastases (37.0% vs. 7.5%) around the left RLN but induced a lower proportion of recurrent nerve injuries (7.4% vs. 22.5%, p = 0.178) compared with VAME. Further analysis revealed that the complete LND around the left RLN was associated with recurrent nerve injury in the RAME (20.0% vs. 5.1%, p = 0.035) and VAME (22.5% vs. 5.7%, p = 0.041) groups but did not affect other clinical outcomes including surgical duration, intraoperative blood loss, postoperative intensive care unit stay, hospital stay, and other complications.

CONCLUSIONS

For patients with ESCC, RAME has great advantages in LND around the left RLN and recurrent nerve protection after learning curve of robotic esophagectomy.

Correlation between operative time and crowd-sourced skills assessment for robotic bariatric surgery

INTRODUCTION

Operative time has been traditionally used as a proxy for surgical skill and is commonly utilized to measure the learning curve, assuming that faster operations indicate a more skilled surgeon. The Global Evaluative Assessment of Robotic Skills (GEARS) rubric is a validated Likert scale for evaluating technical skill. We hypothesize that operative time will not correlate with the GEARS score.

METHODS

Patients undergoing elective robotic sleeve gastrectomy at a single bariatric center of excellence hospital from January 2019 to March 2020 were captured in a prospectively maintained database. For step-specific scoring, videos were broken down into three steps: ligation of short gastric vessels, gastric transection, and oversewing the staple line. Overall and step-specific GEARS scores were assigned by crowd-sourced evaluators. Correlation between operative time and GEARS score was assessed with linear regression and calculation of the R² statistic.

RESULTS

Sixty-eight patients were included in the study, with a mean operative time of 112 ± 27.4 min. The mean GEARS score was 20.1 ± 0.81. Mean scores for the GEARS subcomponents were: bimanual dexterity 4.06 ± 0.17; depth perception 3.96 ± 0.24; efficiency 3.82 ± 0.19; force sensitivity 4.06 ± 0.20; robotic control 4.16 ± 0.21. Operative time and overall score showed no correlation (R² = 0.0146, p = 0.326). Step-specific times and scores showed weak correlation for gastric transection (R² = 0.0737, p = 0.028) and no correlation for ligation of short gastric vessels (R² = 0.0262, p = 0.209) or oversewing the staple line (R² = 0.0142, p = 0.344).

CONCLUSIONS

Operative time and crowd-sourced GEARS score were not correlated. Operative time and GEARS scores measure different performance characteristics, and future studies should consider using both a validated skills assessment tool and operative time for a more complete evaluation of skill.

Lower Incidence of Postoperative Pulmonary Complications Following Robot-Assisted Minimally Invasive Esophagectomy for Esophageal Cancer: Propensity Score-Matched Comparison to Conventional Minimally Invasive Esophagectomy

BACKGROUND

Whether robot-assisted minimally invasive surgery (RAMIE) is more beneficial than conventional minimally invasive surgery (MIE) remains unclear.

METHODS

In total, 165 consecutive patients with esophageal carcinoma who underwent esophagectomy between January 2015 and April 2020 were retrospectively assessed. A 1:1 propensity score matching analysis was performed to compare the short-term outcomes between RAMIE and conventional MIE.

RESULTS

After matching, 45 patients were included in the RAMIE and conventional MIE groups. RAMIE had a significantly longer total operative time (708 vs. 612 min, P < 0.001) and thoracic operative time (348 vs. 285 min, P < 0.001) than conventional MIE. However, there were no significant differences in terms of oncological outcomes, such as R0 resection rate and number of resected lymph nodes. The overall postoperative morbidity (Clavien-Dindo [C-D] grade II or higher) rate of RAMIE and conventional MIE were 51% and 73% (P = 0.03), respectively, and the severe postoperative morbidity (C-D grade III or higher) rates were 11% and 29% (P = 0.04), respectively. The incidence rate of recurrent laryngeal nerve palsy was halved in RAMIE (7%) compared with conventional MIE (20%) (P = 0.06). Finally, the pulmonary complication rate (18%) was significantly lower in patients who underwent RAMIE than in those who underwent conventional MIE (44%) (P = 0.006).

CONCLUSIONS

RAMIE was safe and feasible, even during the early period of its application at a specialized center. Moreover, it may be a promising alternative to conventional MIE, with better short-term outcomes, including significantly lower incidence of pulmonary complications.

Outcomes of robotic esophagectomies for esophageal cancer by hospital volume: an analysis of the national cancer database

BACKGROUND

Robotic minimally invasive esophagectomies (RMIE) have been associated with superior outcomes; however, it is unclear if these are specific to robotic technique or are present only at high-volume institutions. We hypothesize that low-volume RMIE centers would have inferior outcomes.

METHODS

The National Cancer Database (NCDB) identified patients receiving RMIE from 2010 to 2016. Based on the total number of RMIE performed by each hospital system, the lowest quartile performed ≤ 9 RMIE over the study period. Ninety-day mortality, number of lymph nodes evaluated, margins status, unplanned readmissions, length of stay (LOS), and overall survival were compared. Regression models were used to account for confounding.

RESULTS

1565 robotic esophagectomies were performed by 212 institutions. 173 hospitals performed ≤ 9 RMIE (totaling 478 operations over the study period, 30.5% of RMIE) and 39 hospitals performed > 9 RMIE (1087 operations, 69.5%). Hospitals performing > 9 RMIE were more likely to be academic centers (90.4% vs 66.2%, p < 0.001), have patients with advanced tumor stage (65.3% vs 59.8%, p = 0.049), andadministered preoperative radiation (72.8% vs 66.3%, p = 0.010). There were no differences based on demographics, nodal stage, or usage of preoperative chemotherapy. On multivariable regressions, hospitals performing ≤ 9 RMIE were associated with a greater likelihood of experiencing a 90-day mortality, a reduced number of lymph nodes evaluated, and a longer LOS; however, there was no association with rates of positive margins or unplanned readmissions. Median overall survival was decreased at institutions performing ≤ 9 RMIE (37.3 vs 51.5 months, p < 0.001). Multivariable Cox regression demonstrated an association with poor survival comparing hospitals performing ≤ 9 to > 9 RMIE (HR 1.327, p = 0.018).

CONCLUSION

Many robotic esophagectomies occur at institutions which performed relatively few RMIE and were associated with inferior short- and long-term outcomes. These data argue for regionalization of robotic esophagectomies or enhanced training in lower volume hospitals.

Assessment of Quality Outcomes and Learning Curve for Robot-Assisted Minimally Invasive McKeown Esophagectomy

BACKGROUND

This study aimed to identify the results of the quality assessment and the learning curve of robot-assisted minimally invasive McKeown esophagectomy (RAMIE-MK).

METHODS

The study retrospectively reviewed the data of 400 consecutive patients with esophageal cancer who underwent RAMIE-MK by a single surgeon from November 2015 to March 2019. Cumulative summation analysis of the learning curve was performed. The patients were divided into decile cohorts of 40 cases to minimize demographic deviations and to maximize the power of detecting statistically significant changes in performance.

RESULTS

The 90-day mortality rate for all the patients was 0.5% (2 cases). The authors' experience was divided into the ascending phase (40 cases), the plateau phase (175 cases), and the descending phase (185 cases). After 40 cases, significant improvements in operative time (328 vs. 251 min; P = 0.019), estimated blood loss (350 vs. 200 ml; P = 0.031), and conversion rates (12.5% vs. 2.5%; P < 0.001) were observed. After 80 cases, a decrease in the rates of anastomotic leakage (22.5% vs. 8.1%; P = 0.001) and vocal cord palsy (31.3% vs. 18.4%; P = 0.024) was observed. The number of harvested lymph nodes increased after 40 cases (13 vs. 23; P < 0.001), especially for lymph nodes along the recurrent laryngeal nerve (3.0 vs. 6.0; P < 0.001).

CONCLUSIONS

The learning phase of RAMIE-MK consists of 40 cases, and quality outcomes can be improved after 80 procedures. Several turning points related to the optimization of surgical outcomes can be used as benchmarks for surgeons performing RAMIE-MK.

Strategies to prevent anastomotic leakage after esophagectomy and gastric conduit reconstruction

Background

Surgery remains the cornerstone of esophageal cancer treatment but is burdened with high procedure-related morbidity. Anastomotic leakage as the most important surgical complication after esophagectomy is a key indicator for quality in surgical outcome research.

Purpose

The aim of this narrative review is to assess and summarize the current knowledge on prevention of anastomotic leakage after esophagectomy and to provide orientation for the reader in this challenging field of surgery.

Conclusions

There are various strategies to reduce postoperative morbidity and to prevent anastomotic leakage after esophagectomy, including adequate patient selection and preparation, and many technical-surgical and anesthesiological details. The scientific evidence regarding those strategies is highly heterogeneous, ranging from expert’s recommendations to randomized controlled trials. This review is intended to serve as an empirical guideline to improve the clinical management of patients undergoing esophagectomy with a special focus on anastomotic leakage prevention.

Prevention of intra-thoracic recurrent laryngeal nerve injury with robot-assisted esophagectomy

PURPOSE

Transthoracic esophagectomy for esophageal cancer is one of the most invasive procedures in surgery for gastrointestinal cancer. Serious complications sometimes occur after esophageal cancer surgery, including recurrent laryngeal nerve injury and pneumonia. The purpose of this study was to access the possibility of robot-assisted thoracoscopic esophagectomy for esophageal cancer in terms of preventing recurrent laryngeal nerve injury.

METHODS

Operations in thoracic part were performed in prone position with bilateral ventilation. During dissection of the recurrent laryngeal nerve lymph nodes, thin blood vessels were coagulated with Maryland bipolar forceps in the left hand and then dissected with monopolar scissors in the right hand. Especially when dissecting left recurrent laryngeal nerve lymph nodes, the nerve was left unisolated from the vascular sheath that involves the aortic arch. Short-term outcomes including operative time, estimated blood loss, and postoperative complications including recurrent laryngeal nerve injury were accessed.

RESULTS

From November 2018 to January 2020, 20 patients underwent robot-assisted thoracoscopic esophagectomy for esophageal cancer. Thoracic operative time was 242 min, estimated blood loss in the thoracic part was minimal, the number of dissected mediastinal lymph nodes was 19 (all median), and the incidence rates of recurrent laryngeal nerve injury and pneumonia were 10% (2 case) and 10% (2 cases), respectively.

CONCLUSION

Robot-assisted thoracoscopic esophagectomy for esophageal cancer has the possibility of reducing recurrent laryngeal nerve injury even in the introductory period. Randomized controlled trials are required to confirm this advantage of the robotic surgery.

Essential Updates 2018/2019: Essential Updates for esophageal cancer surgery

Key papers to treatment of esophageal cancer surgery and reduction of postoperative complications after esophagectomy published between 2018 and 2019 were reviewed. Within this review there was a focus on minimally invasive esophagectomy (MIE), robot-assisted MIE (RAMIE), and centralization to high-volume center. Advantages of MIE, irrespectively of hybrid or total MIE, to prevent postoperative complications, especially pneumonia, were shown in comparison to open procedure. However, whether total MIE has evident effects or not, as compared to hybrid MIEs, still remains unclear. Differences between RAMIE and MIE were reported to be marginal, though the advantage of lymphadenectomy, especially along recurrent laryngeal nerve, has been suggested. Centralization to high-volume center evidently benefits esophageal cancer patients by improving short-term outcomes. The definition of high-volume center has not been established yet, though institutional structure and quality are thought to be important. Transmediastinal esophagectomy, currently developed, has a potential to be one radical option of MIE for esophageal cancer.

Minimally Invasive Esophagectomy: A Consensus Statement

BACKGROUND

Minimally invasive esophagectomy (MIE) is increasingly performed in various ways. The lack of international definitions and nomenclature makes accurate comparison of outcomes difficult.

METHODS

An international, multispecialty consensus-writing committee constructed definitions and nomenclature for MIE. After a PubMed search, vetting, and review with all authors, a consensus was reached.

RESULTS

The proposed definition for MIE is an operation "that removes part or all of the esophagus, does not retract, lift, spread or remove any part of the chest or abdominal wall and the surgeon's and assistant's vision of the operative field is via a monitor, the patient's tissue is manipulated only by instruments that are controlled by the operating surgeon or team, except for during the neck portion if used." A flexible nomenclature is proposed that attempts to describe current and future operations and systems.

CONCLUSIONS

Definitions and nomenclature for MIE are needed to ensure that future studies accurately compare results and outcomes of similar operations. Nomenclatures allow surgeons, researchers, and patients from different cultures to use a common language to facilitate communication and compare. This process is required in order to improve patient outcomes globally to drive adoption of best of practice, yet is lacking for MIE.

Intrathoracic side-to-side esophagogastrostomy with a linear stapler and barbed suture in robot-assisted Ivor Lewis esophagectomy

Background

The side‐to‐side anastomosis was considered a promising approach to create an intrathoracic esophagogastrostomy in the minimally invasive esophagectomy, with advantages over the side‐to‐end anastomosis with aspects of no need for additional mini‐thoracotomy and lower occurrence of stenosis. The hand‐sewing anterior aspect of the anastomosis is technically challenging in the thoracoscopic Ivor Lewis esophagectomy. Here we introduced our initial experience to facilitate this approach by using the surgical robot and barbed suture.

Methods

A retrospective study of all patients underwent robot‐assisted Ivor Lewis esophagectomy with side‐to‐side esophagogastrostomy from February 2016 to September 2018 was performed. The technical details are described in this paper.

Results

A total of 37 patients (35 male and 2 female, median age of 62.7 years) were successfully treated with completely robot‐assisted Ivor Lewis esophagectomy. The median total surgical time was 340 minutes including 65 minutes to perform the anastomosis. Median estimated blood loss was 120 mL and the length of hospital stay was 10 days. There was no 90‐day mortality. Three patients suffered anastomotic leakage (8.1%,3/37), who were successfully treated without reoperation.

Conclusion

Our initial results imply that it is technically feasible to perform intrathoracic gastroesophageal anastomosis by taking advantage of a robotic system and knotless suturing.

Does robot-assisted minimally invasive esophagectomy really have the advantage of lymphadenectomy over video-assisted minimally invasive esophagectomy in treating esophageal squamous cell carcinoma? A propensity score-matched analysis based on short-term outcomes

This study aims to investigate advantages of robot-assisted minimally invasive esophagectomy (RAMIE) over video-assisted minimally invasive esophagectomy (VAMIE) in treating esophageal squamous cell carcinoma by applying propensity score-matched analysis. From April 2016 to January 2018, consecutive patients undergoing a McKeown RAMIE or VAMIE for esophageal squamous cell carcinoma were prospectively included for analysis. Baseline data, pathological findings, and short-term outcomes of the two groups (RAMIE group and VAMIE group) were collected and compared. Propensity score-matched analysis was applied to generate matched pairs for further comparison. Finally, we included a total of 151 patients (RAMIE group: 79 patients, VAMIE group: 72 patients) for analysis. In the analysis of unmatched cohort, RAMIE yielded a significantly larger number of total dissected lymph nodes (mean: 20.6 ± 8.8 vs. 17.9 ± 7.7; P = 0.048) and abdominal lymph nodes (mean: 9.5 ± 6.8 vs. 7.4 ± 5.1; P = 0.039) than VAMIE. However, there was no significantly different risk of major complications between the two groups. In the analysis of matched cohort, RAMIE still yielded a significantly larger number of total dissected lymph nodes (P = 0.006) and abdominal lymph nodes (P = 0.042) than VAMIE. There was still no increased risk of postoperative major complications in the RAMIE group compared to the VAMIE group. Moreover, RAMIE was found to yield significantly more left recurrent laryngeal nerve lymph nodes (mean: 1.0 ± 1.8 vs. 0.4 ± 0.8; P = 0.033) than VAMIE without increasing the risk of recurrent laryngeal nerve paralysis. Therefore, RAMIE may have the advantage of lymphadenectomy over VAMIE without increasing any risk of postoperative major complications. Further well-conducted studies, however, are needed to confirm our conclusions.

Learning curve for robot-assisted lobectomy of lung cancer

Background

Robotic lobectomy is widely used for lung cancer treatment. So far, few studies have been performed to systematically analyze the learning curve. Our purpose is to define the learning curve to provide a training guideline of this technique.

Methods

A total of 208 consecutive patients with primary lung cancer who underwent robotic-assisted lobectomy by our surgical team were enrolled in this study. Baseline information and postoperative outcomes were collected. Learning curves were then analyzed using the cumulative sum (CUSUM) method. Patients were divided into three groups according to the cut-off points of the learning curve. Intraoperative characteristics and short-term outcomes were compared among the three groups.

Results

CUSUM plots revealed that the docking time, console time and total surgical time in patients were 20, 34 and 32 cases, respectively. Comparison of the surgical time among the 3 phases revealed that the total surgical time (197.03±27.67, 152.61±21.07, 141.35±29.11 min, P<0.001), console time (150.97±26.13, 103.89±18.04, 97.49±24.80 min, P<0.001) and docking time (13.53±2.08, 11.95±1.10, 11.89±1.49 min, P<0.001) were decreased significantly. Estimated blood loss differed among groups (90.63±45.41, 87.63±59.84, 60.29±28.59 mL, P=0.001) and was associated with shorter operative time. There was no conversion or 30-day mortality. No significant differences were observed among other clinic-pathological characteristics among the groups.

Conclusions

For a surgeon, the learning time of robotic lobectomy was in the 32th operation. For a bedside assistant, at least 20 cases were required to achieve the level of optimal docking.

Robot-assisted esophagogastric reconstruction in minimally invasive Ivor Lewis esophagectomy

Background

Although the incidence of esophagogastric junction cancer has increased considerably in recent years, the application of minimally invasive Ivor Lewis esophagectomy, especially in East Asia, is still much rarer than the McKeown approach. The reconstruction of the alimentary tract is one of the main technical challenges under traditional endoscopy. The robotic surgical system with high-resolution 3D images and multiarticulate instruments may help simplify this procedure. Here, we describe our experience in the gastric tube and esophagogastric anastomosis construction, and the initial clinical results for Ivor Lewis robot-assisted minimally invasive esophagectomy (RAMIE).

Methods

A retrospective study of all patients undergoing Ivor Lewis RAMIE with circular stapled anastomosis at a single institution from December 2016 to June 2018 was performed. Operative and postoperative outcomes were recorded.

Results

Twenty-four patients [median age, 63 years (range, 49-77 years)] underwent Ivor Lewis RAMIE during the study period with a four-arm robotic platform. Four patients (16.7%) received neoadjuvant therapy. The median estimated blood loss was 120 mL (range, 50-210 mL). The median operating time was 352.5 min (range, 259-485 min). There was no conversion to an open surgical procedure. Postoperative complications occurred in 3 (12.5%) patients. Complications included pneumonia in two patients (8.3%) and mediastinitis in 1 (4.2%). The median stay in the intensive care unit was 1 d (range, 0-8 d) and the median postoperative hospital stay was 11 d (range, 8-30 d). All patients had an R0 resection. The median number of nodes removed was 19 (range, 11-30) and the median number of positive nodes removed was 1 (range, 0-8).

Conclusions

Our initial results indicate that Ivor Lewis RAMIE may be a safe and feasible alternative to open and endoscopic Ivor Lewis esophagectomy.

Learning curve and postoperative outcomes of minimally invasive esophagectomy

Surgical innovation is necessary to increase surgical effectiveness and to decrease postoperative complications, but can be associated with learning curves. The significance of surgical learning curves is increasing and it is important to take surgical learning curves into account when interpreting outcome data that is acquired during an implementation period. This may especially be the case for a technically challenging procedure like minimally invasive esophagectomy (MIE). This review article provides an overview of the published literature that has described a learning curve for MIE, with particular interest in the relationship between the learning curve and postoperative complications. Twenty two studies reported learning curves of different types of MIE. These studies showed that the length of the learning curve of MIE can be significant, but most studies are single center studies of limited methodological quality. In addition, several learning curve analysis methods are used but a clear recommendation regarding the preferred method is lacking. Most studies use intraoperative parameters (e.g., operative time) to define the length of the learning curve. However, significant learning curve effects have been found for clinically more relevant parameters (e.g., anastomotic leak), especially for Ivor Lewis MIE. These studies suggest that patient safety can be substantially compromised during learning curves. To increase patient safety and shorten the learning curve, evidence based and effective safe implementation programs are necessary.

Current status of minimally invasive esophagectomy for esophageal cancer: Is it truly less invasive?

Esophagectomy with extended lymphadenectomy remains the mainstay of treatment for localized esophageal cancer. However, it is one of the most invasive procedures with high morbidity. To reduce invasiveness, minimally invasive esophagectomy (MIE), which includes thoracoscopic, laparoscopic, mediastinoscopic, and robotic surgery, is becoming popular worldwide. Thoracoscopic esophagectomy in the prone position is ergonomic for the surgeon and has better perioperative arterial oxygen pressure/fraction of inspired oxygen (P/F) ratio. Thoracoscopic esophagectomy in the left decubitus position is easy to introduce because it is similar to standard right posterolateral open esophagectomy (OE) in position. It has a relatively short operative time. Laparoscopic approach could potentially have a substantial effect on pneumonia prevention under the condition of thoracotomy. Mediastinoscopic surgery has the potential to reduce pulmonary complications because it can avoid a transthoracic procedure. In robotic surgery, in the future, less recurrent laryngeal nerve palsy will be expected as a result of polyarticular fine maneuvering without human tremors. In studies comparing MIE with OE, mediastinoscopic surgery and robotic surgery are usually not included; these studies show that MIE has a longer operative time and less blood loss than OE. MIE is particularly beneficial in reducing postoperative respiratory complications such as atelectasis, despite no dramatic decrease in pneumonia. Reoperation might occur more frequently with MIE. There is no significant difference in mortality rate between MIE and OE. It is important to recognize that the advantages of MIE, particularly "less invasiveness", can be of benefit at facilities with experienced medical personnel.

Minimally Invasive Esophageal Cancer Surgery

Laparoscopic and thoracoscopic or robotic-assisted minimally invasive esophagectomy offers benefits in decreased postoperative complications and faster recovery. The choice of operation depends on patient and surgeon factors. McKeown or 3-field esophagectomy requires dissection in the abdomen, chest, and neck, with a cervical anastomosis. Ivor Lewis esophagectomy is performed with abdominal and right chest dissection and intrathoracic anastomosis. Transhiatal or transmediastinal esophagectomy is performed with abdominal and cervical dissections and a cervical anastomosis and is preferential in patients with significant pulmonary risk factors. Preparation and operative conduct for laparoscopic and robotic approaches for these operations, and the expected postoperative recovery are detailed.