The Learning Curve of Robotic-Assisted Low Rectal Resection of a Novice Rectal Surgeon

Impact of team experience on robot-assisted surgery for rectal cancer: A comparative study

INTRODUCTION

The robotic surgical team in the operating room plays an important role in determining the outcome of a robotic approach. This study aimed to compare the outcomes of 2 hospitals with different levels of expertise in robot-assisted rectal cancer surgery.

METHODS

This retrospective study analyzed 195 patients who underwent robot-assisted rectal resection at 2 referral centers for the treatment of rectal cancer between March 2018 and December 2021.

RESULTS

In total, 195 patients had undergone robotic rectal cancer surgery: 95 performed by an expert team, and 100 by a novel team. The expert team performed more low anterior resections (55.8%) than the novel team (33%) (P = 0.001), and the total operative time varied significantly between the groups (P < 0.001). The novel team's operative time was 135 min longer than the expert team's. The expert team had no conversions to open surgery, while the novel team had an 8% conversion rate (P = 0.007). In this study, overall morbidity was 45.3% among patients treated by the expert team versus 38% among those treated by the novice team (P = 0.304). Severe complications (Clavien-Dindo grade >IIIB) occurred at a rate of 10% in both groups. Incomplete mesorectal excision was observed in 3.2% of the expert team's patients versus 4.2% of the novice team's (P = 0.65).

CONCLUSION

The expert team achieved a shorter operative time and less conversion to open surgery. However, the morbidity and pathological outcomes were comparable between the teams. The introduction of robotic surgery in a team with early-stage surgical experience was safe.

Learning Curve for Robotic Colorectal Surgery

With the increasing adoption of robotic surgery in clinical practice, institutions intending to adopt this technology should understand the learning curve in order to develop strategies to help its surgeons and operating theater teams overcome it in a safe manner without compromising on patient care. Various statistical methods exist for the analysis of learning curves, of which a cumulative sum (CUSUM) analysis is more commonly described in the literature. Variables used for analysis can be classified into measures of the surgical process (e.g., operative time and pathological quality) and measures of patient outcome (e.g., postoperative complications). Heterogeneity exists in how performance thresholds are defined during the interpretation of learning curves. Factors that influence the learning curve include prior surgical experience in colorectal surgery, being in a mature robotic surgical unit, case mix and case complexity, robotic surgical simulation, spending time as a bedside first assistant, and being in a structured training program with proctorship.

Comparison of short-term outcomes of laparoscopic surgery, robot-assisted laparoscopic surgery, and open surgery for lateral lymph-node dissection for rectal cancer: a network meta-analysis

This study attempted to compare short-term outcomes of laparoscopic surgery (LS), robot-assisted laparoscopic surgery (RS), and open surgery (OS) for lateral lymph-node dissection (LLND) in treatment of rectal cancer through network meta-analysis. Embase, Web of Science, PubMed, and The Cochrane Library databases were searched to collect cohort studies on outcomes of LS, RS, and OS for LLND for rectal cancer. Newcastle-Ottawa Scale (NOS) was utilized to evaluate the quality of cohort studies. Primary outcomes should at least include one of the following clinical outcome measures: operative time, blood loss, total lymph-node harvest, positive resection margin rate, postoperative complications, and postoperative hospital stay. A network meta-analysis was conducted using STATA software. Fourteen cohort studies including 8612 patients were eligible for inclusion. The network meta-analysis results showed that, in terms of intraoperative outcomes, the RS group had the longest operative time, while the OS group had the shortest; the LS and RS groups had significantly less blood loss than the OS group. In terms of histological outcomes, there were no significant differences in the total number of lymph nodes harvested and the positive margin rate among the LS, RS, and OS groups (P > 0.05). Regarding postoperative outcomes, the OS group had the highest probability of postoperative complications and the longest hospital stay, followed by the LS group, with the RS group being the lowest. RS was the best method in blood loss, postoperative complication rate, and postoperative hospital stay, followed by LS. OS had the shortest operative time and the highest blood loss.

Robotic Proctectomy: Beyond the Initial Learning Curve

BACKGROUND

Multiple authors have described an initial learning curve (LC) for robotic proctectomy (RP), but there is scant literature regarding continued technical progression beyond this stage. Total operating time is the most commonly used metric to measure proficiency. Our goal was to examine RP experience after the initial LC looking for evidence of further technical progression.

METHODS

We reviewed our robotic surgery database for a single surgeon during operations 100 through 550 to identify 83 RPs for tumor. These were divided into quartiles by series order, indicating surgeon experience level over time. Demographics and outcomes were compared among the groups. We defined percent console time (PCT) as a new metric. PCT was defined as console time divided by total operative time (TOT).

RESULTS

From March 2014 through March 2019, 450 robotic colorectal operations were performed, including 83 RPs for polyp or cancer. No significant differences were found among the quartiles in regard to demographics, tumor features, hospital stay, conversions, or readmissions. As experience was gained, there were significant increases in intracorporeal anastomosis (ICA), TOT, and PCT. Complications decreased with experience. Number of lymph nodes in the specimen increased. On multivariate analysis, later experience group, body mass index ≥30, and ICA were associated with increased PCT.

DISCUSSION

ICA became a routine part of RP after the initial LC, with increases in TOT and PCT. Number of lymph nodes increased and number and severity of complications decreased with experience. Increased PCT may indicate increased expertise during RP.

Transition from laparoscopic to robotic approach in rectal cancer: a single-center short-term analysis based on the learning curve

As a novel procedure becomes more and more used, knowledge about its learning curve and its impact on outcomes is useful for future implementations. Our aim is (i) to identify the phases of the robotic rectal surgery learning process and assess the safety and oncological outcomes during that period, (ii) to compare the robotic rectal surgery learning phases outcomes with laparoscopic rectal resections performed before the implementation of the robotic surgery program. We performed a retrospective study, based on a prospectively maintained database, with methodological quality assessment by STROBE checklist. All the procedures were performed by the same two surgeons. A total of 157 robotic rectal resections from June 2018 to January 2022 and 97 laparoscopic rectal resections from January 2018 to July 2019 were included. The learning phase was completed at case 26 for surgeon A, 36 for surgeon B, and 60 for the center (both A & B). There were no differences in histopathological results or postoperative complications between phases, achieving the same ratio of mesorectal quality, circumferential and distal resection margins as the laparoscopic approach. A transitory increase of major complications and anastomotic leakage could occur once overcoming the learning phase, secondary to the progressive complexity of cases. Robotic rectal cancer surgery learning curve phases in experienced laparoscopic surgeons was completed after 25-35 cases. Implementation of a robotic rectal surgery program is safe in oncologic terms, morbidity, mortality and length of stay.

Learning curve for robotic rectal cancer resection at a community-based teaching institution

The surgical management of rectal cancer is shifting toward more widespread use of robotics across a spectrum of medical centers. There is evidence that the oncologic outcomes are equivalent to laparoscopic resections, and the post-operative outcomes may be improved. This study aims to evaluate the learning curve of robotic rectal cancer resections at a community-based teaching institution and evaluate clinical and oncologic outcomes. A retrospective review of consecutive robotic rectal cancer resections by a single surgeon was performed for a five-year period. The cumulative sum (CUSUM) for total operative time was calculated and plotted to establish a learning curve. The oncologic and post-operative outcomes for each phase were analyzed and compared. The CUSUM learning curve yielded two phases, the learning phase (cases 1-79) and the proficiency phase (cases 80-130). The median operative time was significantly lower in the proficiency phase. The type of neoadjuvant therapy used between the two groups was statistically different, with chemoradiation being the primary regimen in the learning phase and total neoadjuvant therapy being more common in the proficiency phase. Otherwise, oncologic and overall post-operative outcomes were not significantly different between the groups. Robotic rectal resections can be done in a community-based hospital system by trained surgeons with outcomes that are favorable and similar to larger institutions.

Prospective analysis of impact of learning curve in robotic-assisted rectal surgery in the high-volume Indian tertiary care centre

Background

Minimally invasive surgery in rectal cancer has gained prominence owing to its various advantages in surgical outcomes. Due to rapid adoption of robotics in rectal surgery, we intended to assess the pace in which surgeons gain proficiency using cumulative summation (CUSUM) technique in learning curve.

Materials and Methods

This was a prospective study of 262 rectal cancer cases who underwent robotic-assisted low anterior resection and abdominoperineal resection (RA-LAR and RA-APR). Parameters considered for the study were console time, docking time, lymph nodal yield, total operative time and post-operative outcomes. We used Manipal technique of port placements and modified centroside docking for the procedure.

Results

The mean age of our study was 46.62 ± 5.7 years, the mean body mass index (BMI) was 31.51 ± 3.2 kg/m2. 215 (82.06%) underwent RA-LAR and 47 (17.93%) underwent RA-APR. 2.67% of cases required to open during our initial period. We had three phases of learning curve, initial phase (11th case), plateau phase (29th case) and then phases of mastery (30th case onwards). Our mean total operative time reduced from 5.5 to 3.5 h (210 ± 8.2 min), console time from 4.5 to 2.9 h (174 ± 4.5 min) and docking time from 15 to 9 ± 1 min from 30th case onwards.

Conclusion

RA surgeries for rectal cancer have got good oncological and functional outcomes in high BMI, male pelvis and low rectal cancers. Learning curve can be shortened with constant self-auditing of the surgeon and team with each surgeries performed, reviewing the steps and by improving techniques.

Learning curve for robotic-assisted total mesorectal excision: a multicentre, prospective study

AIM

Robotic-assisted surgery (RAS) is becoming increasingly important in colorectal surgery. Recognition of the short, safe learning curve (LC) could potentially improve implementation. We evaluated the extent and safety of the LC in robotic resection for rectal cancer.

METHOD

Consecutive rectal cancer resections (January 2018 to February 2021) were prospectively included from three French centres, involving nine surgeons. LC analyses only included surgeons who had performed more than 25 robotic rectal cancer surgeries. The primary endpoint was operating time LC and the secondary endpoint conversion rate LC. Interphase comparisons included demographic and intraoperative data, operating time, conversion rate, pathological specimen features and postoperative morbidity.

RESULTS

In 174 patients (69% men; mean age 62.6 years) the mean operating time was 334.5 ± 92.1 min. Operative procedures included low anterior resection (n = 143) and intersphincteric resection (n = 31). For operating time, there were two or three (centre-dependent) LC phases. After 12-21 cases (learning phase), there was a significant decrease in total operating time (all centres) and an increase in the number of harvested lymph nodes (two centres). For conversion rate, there were two or four LC phases. After 9-14 cases (learning phase), the conversion rate decreased significantly in two centres; in one centre, there was a nonsignificant decrease despite the treatment of significantly more obese patients and patients with previous abdominal surgery. There were no significant differences in interphase comparisons.

CONCLUSION

The LC for RAS in rectal cancer was achieved after 12-21 cases for the operating time and 9-14 cases for the conversion rate. RAS for rectal cancer was safe during this time, with no interphase differences in postoperative complications and circumferential resection margin.

Robotic versus laparoscopic approach for minimally invasive lateral pelvic lymph node dissection of advanced lower rectal cancer: a retrospective study comparing short-term outcomes

PURPOSE

The importance of lateral pelvic lymph node dissection (LLND) for advanced low rectal cancer is gradually being recognized in Europe and the USA, where some patients were affected by uncontrolled lateral pelvic lymph node (LLNs) metastasis, even after total mesorectal excision (TME) with neoadjuvant chemoradiotherapy (CRT). The purpose of this study was thus to compare robotic LLND (R-LLND) with laparoscopic (L-LLND) to clarify the safety and advantages of R-LLND.

METHODS

Sixty patients were included in this single-institution retrospective study between January 2013 and July 2022. We compared the short-term outcomes of 27 patients who underwent R-LLND and 33 patients who underwent L-LLND.

RESULTS

En bloc LLND was performed in significantly more patients in the R-LLND than in the L-LLND group (48.1% vs. 15.2%; p = 0.006). The numbers of LLNs on the distal side of the internal iliac region (LN 263D) harvested were significantly higher in the R-LLND than in the L-LLND group (2 [0-9] vs. 1 [0-6]; p = 0.023). The total operative time was significantly longer in the R-LLND than in the L-LLND group (587 [460-876] vs. 544 [398-859]; p = 0.003); however, the LLND time was not significantly different between groups (p = 0.718). Postoperative complications were not significantly different between the two groups.

CONCLUSION

The present study clarified the safety and technical feasibility of R-LLND with respect to L-LLND. Our findings suggest that the robotic approach offers a key advantage, allowing significantly more LLNs to be harvested from the distal side of the internal iliac region (LN 263D). Prospective clinical trials examining the oncological superiority of R-LLND are thus necessary in the near future.

Learning curve of robotic rectal surgery using risk-adjusted cumulative summation: a 5-year institutional experience

PURPOSE

Outline learning phases of robot-assisted laparoscopic surgery for rectal cancer and compare surgical and clinical outcomes between each phase of robot-assisted laparoscopic surgery and the mastery phase of conventional laparoscopic surgery.

METHODS

From 2015 to 2020, 210 patients underwent rectal cancer surgery at Sendai Medical Center. We performed conventional laparoscopic surgery in 110 patients and, laparoscopic surgery in 100 patients. The learning curve was evaluated using the cumulative summation method, risk-adjusted cumulative summation method, and logistic regression analysis.

RESULTS

The risk-adjusted cumulative summation learning curve was divided into three phases: phase 1 (cases 1-48), phase 2 (cases 49-80), and phase 3 (cases 81-100). Duration of hospital stay (13.1 days vs. 18.0 days, respectively; p = 0.016) and surgery (209.1 min vs. 249.5 min, respectively; p = 0.045) were significantly shorter in phase 3 of the robot-assisted laparoscopic surgery group than in the conventional laparoscopic surgery group. Blood loss volume was significantly lower in phase 1 of the robot-assisted laparoscopic surgery group than in the conventional laparoscopic surgery group (17.7 ml vs. 79.7 ml, respectively; p = 0.036). The International Prostate Symptom Score was significantly lower in the robot-assisted laparoscopic surgery group (p = 0.0131).

CONCLUSIONS

Robot-assisted laparoscopic surgery for rectal cancer was safe and demonstrated better surgical and clinical outcomes, including a shorter hospital stay, less blood loss, and a shorter surgical duration, than conventional laparoscopic surgery. After experience with at least 80 cases, tactile familiarity can be acquired from visual information only (visual haptic feedback).

CLINICAL TRIAL REGISTRATION

UMIN reference no. UMIN000019857.

The robotic learning curve for a newly appointed colorectal surgeon

Robotic colorectal surgery allows for better ergonomics, superior retraction, and fine movements in the narrow anatomy of the pelvis. Recent years have seen the uptake of robotic surgery in all pelvic surgeries specifically in low rectal malignancies. However, the learning curve of robotic surgery in this cohort is unclear as established training pathways are not formalized. This study looks at the experience and learning curve of a single laparoscopic trained surgeon in performing safe and effective resections, mainly for low rectal and anal malignancies using the da Vinci robotic system by evaluating metrics related to surgical process and patient outcome. A serial retrospective review of the robotic colorectal surgery database, in the University Hospital Coventry and Warwickshire (UHCW), was undertaken. All 48 consecutive cases, performed by a recently qualified colorectal surgeon, were included in our study. The surgical process was evaluated using both console and total operative time recorded in each case along with the adequacy of resections performed; in addition, patient-related outcomes including intraoperative and postoperative complications were analyzed to assess differences in the learning curve. Forty eight sequential recto-sigmoid resections were included in the study performed by a single surgeon. The cases were divided into four cohorts in chronological order with comparable demographics, tumour stage, location, and complexity of the operation (mean age 65, male 79%, and female 29%). The results showed that the mean console time dropped from 3 to 2.5 h, while total operative time dropped from 6 h to 5.5 h as the surgeon became more experienced; however, this was not found to be statistically significant. In addition, no significant difference in pathological staging was seen over the study period. No major intra-op and post-op complications were observed and no 30-day mortality was recorded. Moreover, after 30 cases, the learning curve developed the plateau phase, suggesting the gain of maximum proficiency of skills required for robotic colorectal resections. The learning curve in robotic rectal surgery is short and flattens early; complication rates are low during the learning curve and continue to decrease with time. This shows that with proper training and proctoring, new colorectal surgeons can be trained in a short time to perform elective colorectal pelvic resections.

Seniority of the assistant surgeon and perioperative outcomes in robotic-assisted proctectomy for rectal cancer

The background of this study is to evaluate the impact of the assistant surgeon's in robotic-assisted proctectomy (RAP) on perioperative outcomes. A retrospective analysis of all patients who underwent RAP for rectal adenocarcinoma between 2011 and 2020 was conducted. Patient cohort was divided into three groups based on the assistant surgeon's training level: post-graduate years (PGY) 1-3 surgical residents (Group 1), PGY 4-5 surgical residents (Group 2), and board-certified general surgeons (Group 3). Overall, 175 patients were included in the study: 29 patients (17%) in Group 1, 84 (48%) in Group 2, and 62 (35%) in Group 3. The median tumor distance from the anal verge was 8 cm in all groups (p = 0.73). The median operative time was similar across all groups: 290, 291, and 281 min in Groups 1, 2, and 3, respectively (p = 0.69). In a multivariable analysis, the lack of association between assistant training level and procedure time maintained when adjusting for the year of operation (p = 0.84). Patients operated with junior residents as assistant surgeons (Group 1) had a more postoperative complications (p = 0.01) and a slightly longer hospital length of stay [7 days, interquartile range (IQR) 3], compared to those operated by assistant surgeons that were senior residents or attendings (6 IQR 2.5, and 6 IQR 2 in Groups 2 and 3, respectively; p = 0.02). Conversion rates (p = 0.12), intraoperative complications (p = 0.39), major postoperative complications (Clavien-Dindo ≥ 3; p = 0.32), 30-day readmission (p = 0.45), and mortality (p = 0.99) were similar between the groups. Robotic-assisted proctectomy performed with the assistance of a junior resident was found to be correlated with worse postoperative outcomes compared to more experienced assistants. No difference was seen in intraoperative outcomes.

The learning curve of laparoscopic, robot-assisted and transanal total mesorectal excisions: a systematic review

BACKGROUND

The standard treatment of rectal carcinoma is surgical resection according to the total mesorectal excision principle, either by open, laparoscopic, robot-assisted or transanal technique. No clear consensus exists regarding the length of the learning curve for the minimal invasive techniques. This systematic review aims to provide an overview of the current literature regarding the learning curve of minimal invasive TME.

METHODS

A systematic literature search was performed. PubMed, Embase and Cochrane Library were searched for studies with the primary or secondary aim to assess the learning curve of either laparoscopic, robot-assisted or transanal TME for rectal cancer. The primary outcome was length of the learning curve per minimal invasive technique. Descriptive statistics were used to present results and the MINORS tool was used to assess risk of bias.

RESULTS

45 studies, with 7562 patients, were included in this systematic review. Length of the learning curve based on intraoperative complications, postoperative complications, pathological outcomes, or a composite endpoint using a risk-adjusted CUSUM analysis was 50 procedures for the laparoscopic technique, 32-75 procedures for the robot-assisted technique and 36-54 procedures for the transanal technique. Due to the low quality of studies and a high level of heterogeneity a meta-analysis could not be performed. Heterogeneity was caused by patient-related factors, surgeon-related factors and differences in statistical methods.

CONCLUSION

Current high-quality literature regarding length of the learning curve of minimal invasive TME techniques is scarce. Available literature suggests equal lengths of the learning curves of laparoscopic, robot-assisted and transanal TME. Well-designed studies, using adequate statistical methods are required to properly assess the learning curve, while taking into account patient-related and surgeon-related factors.

Learning Curve of Robotic-Assisted Total Mesorectal Excision for Rectal Cancer

Background

Although some studies have assessed the learning curve of robotic-assisted total mesorectal excision for rectal cancer, most studies included limited sample sizes, no study used postoperative complications as an independent variable to analyze the learning curve of robotic rectal surgery, and no study evaluated the influence of the learning curve on long-term oncologic outcomes.

Methods

Clinical data on consecutive patients who underwent robotic-assisted total mesorectal excision for rectal cancer by a single surgeon between January 2015 and December 2018 at the First Affiliated Hospital of Nanchang University were retrospectively collected. The cumulative sum (CUSUM) and risk-adjusted cumulative sum (RA-CUSUM) were used to visualize the learning curve of operation time and postoperative complications (CD ≥ grade II). Comparisons of clinical outcomes at different learning phases analyzed by RA-CUSUM were performed after propensity score matching.

Results

A total of 389 consecutive patients were included in the analysis. The numbers of patients needed to overcome the learning curves of operation time and postoperative complications of robotic-assisted laparoscopic surgery for rectal cancer were 34 and 36, respectively. The learning process was divided into two phases based on RA-CUSUM: the learning phase (1st-36th cases) and the mastery phase (37th-389th cases). Before matching, the mastery phase had more patients with older age, lower tumor location, and neoadjuvant therapy. After matching, the two phases exhibited similar characteristics. The operation time, intraoperative blood loss, postoperative hospital stay, and postoperative complications in the mastery phase were reduced compared with the learning phase, with a median follow-up of 35 months, and the long-term oncologic outcomes were not significantly different between the two phases.

Conclusions

An experienced laparoscopic surgeon initially implements robotic-assisted total mesorectal excision for rectal cancer, surgical outcomes improved after 36 cases, and the learning curve seemingly did not have an obvious impact on long-term oncologic outcomes.

Factors affecting the learning curve in robotic colorectal surgery

Learning related to robotic colorectal surgery can be measured by surgical process (such as time or adequacy of resection) or patient outcome (such as morbidity or quality of life). Time based metrics are the most commonly used variables to assess the learning curve because of ease of analysis. With analysis of the learning curve, there are factors which need to be considered because they may have a direct impact on operative times or may be surrogate markers of clinical effectiveness (unrelated to times). Variables which may impact on operation time include surgery case mix, hybrid technique, laparoscopic and open colorectal surgery experience, robotic surgical simulator training, technology, operating room team, and case complexity. Multidimensional analysis can address multiple indicators of surgical performance and include variables such as conversion rate, complications, oncological outcome and functional outcome. Analysis of patient outcome and/or global assessment of robotic skills may be the most reliable methods to assess the learning curve.

The learning curve to attain surgical competency in robotic colorectal surgery

INTRODUCTION

The aim of the study was to assess the robotic colorectal surgery (RCS) learning curve of an experienced surgeon.

METHODS

A retrospective review of 117 consecutive patients who underwent total RCS at a single institution between October 2018 and July 2021 was performed. Patient demographics, surgery indications, operation type, intraoperative data, histopathology, morbidity and mortality, and length of stay were analysed. Cumulative summation technique (CUSUM) was used to construct a learning curve of surgeon console and total operation times (SCT and TOT).

RESULTS

There was no open conversion, positive resection margin and mortality in the study population. There were four Clavien-DIndo grade III complications and one local recurrence. The range for SCT was 18-855 min (mean 214, median 211) and TOT was 68-937 min (mean 302, median 291). The SCT CUSUM graph identified change in slope at cases 44 and 88, which divided the learning curve into three distinct phases. Patient demographics were similar through the three phases. There was proportionally more cancer cases performed in the first phase (P = 0.001). The mean SCT was significantly higher in Phase 2 when compared with Phases 1 and 3 (P = 0.03). The failure rate was similar through the three phases. There was a non-significant steady decline in LOS over the three phases, from 6.9 to 6.1 days.

CONCLUSION

Experienced colorectal surgeons can perform robotic surgery safely, even on patients with high complexity early in the learning curve. Audit of patient outcome should be an important component of learning curve assessment.

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.

Current status and role of robotic approach in patients with low-lying rectal cancer

Utilization of robotic surgical systems has increased over the years. Robotic surgery is presumed to have advantages of enhanced visualization, improved dexterity, and reduced tremor, which is purported to be more suitable for rectal cancer surgery in a confined space than laparoscopic or open surgery. However, evidence supporting improved clinical and oncologic outcomes after robotic surgery remains controversial and limited despite the widespread adoption of robotic surgical systems. To date, numerous observational studies and a few randomized controlled trials have failed to demonstrate that short-term, oncological, and functional outcomes after a robotic surgery are superior to those of laparoscopic surgery for low rectal cancer patients. The objective of this review is to summarize the current state of robotic surgery and its impact on low-lying rectal cancer.

Learning curve for robotic bedside assistance for rectal cancer: application of the cumulative sum method

BACKGROUND

This investigation assesses the learning curve for dedicated bedside assistance at a facility that recently adopted robot-assisted rectal resection.

METHODS

Data from patients with rectal cancer who underwent robotic rectal resections from September 2019 through April 2020 were retrospectively analyzed. Before starting robotic surgery, we set the rule that a console surgeon would not enter the sterile field and all of those maneuvers would be left to a dedicated physician. Docking time was analyzed using the cumulative sum (CUSUM) method to evaluate the learning curve. Different phases in the learning curve were identified according to CUSUM plot configuration. A comparison was made of phases 1 and 2 combined, and phase 3.

RESULT

The procedures were performed in 30 patients. Median docking time, console time was 13 min. A total of nine patients had histories of abdominal surgery. CUSUM analysis of docking time demonstrated 3 phases. Each docking time was longer in Phase 1 (the first 3 cases) than the average docking time over the all cases. The docking time in Phase 2 (the 9 middle cases) approximated the average time over the all cases. Phase 3 (the remaining 18 cases) showed further improvement of the docking procedure and time was reduced. A comparison of Phases 1 and 2 combined, and Phase 3, revealed that Phase 3 had a significantly higher rate of history of abdominal surgery.

CONCLUSION

Docking manipulation proficiency was achieved in approximately 10 cases without the influence of surgical difficulty.

The learning curve in robotic colorectal surgery compared with laparoscopic colorectal surgery: a systematic review

AIM

The learning curve has implications for efficient surgical training. Robotic surgery is perceived to have a shorter learning curve than laparoscopy; however, detailed analysis is lacking. The aim of this work was to analyse studies comparing robotic and laparoscopic colorectal learning curves. Simulation studies comparing novices' learning curves were analysed in order to surmise applicability to colorectal surgery.

METHOD

A systematic search of Medline, PubMed, Embase and the Cochrane Library identified colorectal papers (from 1 January 2000 to 3 March 2021) comparing robotic and laparoscopic learning curves where surgeons lacked laparoscopic colorectal experience. Simulation studies comparing learning curves were also included. The learning curve was defined as the period of ongoing improvement in speed and/or accuracy.

RESULTS

From 576 abstracts reviewed, three operative and 16 simulation studies were included. The robotic learning curve for right colectomy was significantly faster in one study (16 vs. 25 cases) and equal for anterior resection in two studies (44 vs. 41 cases and 55 vs. 55). One study showed fewer complications for robotic patients (14.6% vs. 0%, p = 0.013). Ten simulation studies reported faster times and eight recorded error rates favouring robotic surgery. Seven studies measured the learning curve. Four favoured laparoscopic surgery, but operating times were faster using the robotic platform.

CONCLUSION

Operating times for robotic surgery may be faster than laparoscopy when surgeons are inexperienced with both platforms. This may be related to a superior baseline performance rather than a shorter learning curve. Whether a shorter learning curve on the laparoscopic platform will persist for long enough to enable skills to overtake robotic ability needs further investigation.

Update on Minimally Invasive Surgical Approaches for Rectal Cancer

PURPOSE OF REVIEW

This review aims to clarify the current role of minimally invasive surgery in the treatment of rectal cancer, highlighting short- and long-term outcomes from the latest trials and studies.

RECENT FINDINGS

Data from previous trials has been conflicting, with some failing to demonstrate non-inferiority of laparoscopic surgical resection of rectal cancer compared to an open approach and others demonstrating similar clinical outcomes. Robot-assisted surgery was thought to be a promising solution to the challenges faced by laparoscopic surgery, and even though the only randomized controlled trial to date comparing these two techniques did not show superiority of robot-assisted surgery over laparoscopy, more recent retrospective data suggests a statistically significant higher negative circumferential resection margin rate, decreased frequency of conversion to open, and less sexual and urinary complications. Minimally invasive surgery techniques for resection of rectal cancer, particularly robot-assisted, offer clear short-term peri-operative benefits over an open approach; however, current data has yet to display non-inferiority in terms of oncological outcomes.

Initial Experience in Rectal Cancer Surgery for the Next Generation of Robotic Surgeons Trained in a Dual Console System

BACKGROUND

Robotic surgery for rectal cancer is used worldwide, with an increasing incidence of robotic surgeons. Therefore, the most appropriate educational system for next-generation robotic surgeons should be urgently established.

METHODS

We analyzed 39 patients who underwent robotic rectal surgery performed by a next-generation surgeon with limited experienced in laparoscopic rectal cancer surgery. The dual console system was used in the initial 15 cases, and we assessed short-term outcomes and the learning curve on operative time using the cumulative sum method.

RESULTS

The patients were divided into two groups: 15 cases in the early phase, and 24 cases in the late phase. The operative time and surgeon console time were significantly shorter in the late phase than the early phase (P < 0.001). Postoperative complications were more frequently observed in the early phase (P = 0.049); however, the estimated blood loss and length of hospital stay were not significantly different. In the initial 15 cases that using the dual console, the average operative time changing to the expert surgeon was 82 minutes in the first 5 cases, 19 minutes on average in the next 5 cases, and no change occurred in the last 5 cases. The learning curve peaked after 14 cases, plateaued from case number 15 to 23, and decreased in a linear fashion until the final case.

CONCLUSION

Education of a next generation surgeon using a dual console system for robotic rectal cancer surgery was performed safely.

Simultaneous Robot Assisted Colon and Liver Resection for Metastatic Colon Cancer

Introduction

Simultaneous robot assisted colon and liver resections are being performed more frequently at present due to the expanded adoption of the robotic platform for surgical management of metastatic colon cancer. However, this approach has not been studied in detail with only case series available in the literature. The aim of this systematic review was to evaluate the current body of evidence on the feasibility of performing simultaneous robotic colon and liver resections.

Methods

A systematic review was performed through PubMed to identify relevant articles describing simultaneous colon and liver resections for metastatic colon cancer.

Results

A total of 28 patients underwent simultaneous resections robotically with an average operative time of 420.3 minutes and average blood loss of 275.6 ml. Postoperative stay was 8.6 days on average with all cases achieving negative surgical margins.

Conclusions

Robotic simultaneous resection of colorectal cancer with liver metastases is technically feasible and seems oncologically equivalent to open or laparoscopic surgery. Further studies are urgently needed to assess benefits of robotic surgery in the patient population.

Robotic versus laparoscopic ileal pouch-anal anastomosis (IPAA): a systematic review and meta-analysis

BACKGROUND

Restorative proctocolectomy with ileal-pouch anal anastomosis (IPAA) is a curative and cancer preventative procedure in patients with ulcerative colitis (UC) and familial adenomatous polyposis (FAP). It can be technically difficult laparoscopically, and hence the robotic platform has been suggested as a way to enable minimally invasive surgery in more patients. This systematic review examines robotic proctectomy or proctocolectomy with IPAA. A limited meta-analysis was performed on data comparing the robotic approach to laparoscopy.

METHODS

We searched MEDLINE, EMBASE and the Cochrane database for case series of robotic IPAA procedures and studies comparing the robotic to laparoscopic or open procedures. Data examined includes operating time, conversion to open, length of stay, complications, blood loss, return of bowel function, reoperation rate and functional outcomes.

RESULTS

Five non-randomised studies compared robotic to laparoscopic techniques; one compared robotic to open surgery and three case series are included. Operating time was significantly longer in robotic cases. Estimated blood loss was significantly less in three of four studies which reported this; hospital stay was significantly less in two. There were nonsignificant reductions in complications and readmission rates. Pooled analysis of four papers with adequate data showed a nonstatistically significant trend to less complications in robotic procedures. Three studies assessed functional and quality of life outcomes, with little difference between the platforms.

CONCLUSIONS

Available data suggests that the robotic platform is safe to use for IPAA procedures. There is minimal evidence for clinical advantages, but with little data to base decisions and significant potential for improvements in technique and cost-effectiveness, further use of the platform for this operation is warranted. It is vital that this occurs within an evaluation framework.

Short-term outcomes of robotic-assisted versus conventional laparoscopic-assisted surgery for rectal cancer: a propensity score-matched analysis

It remains controversial whether the advantages of robotic-assisted surgery are beneficial for rectal cancer (RC). The study aimed to evaluate the short-term outcomes of robotic-assisted rectal surgery (RARS) compared with those of conventional laparoscopic-assisted rectal surgery. We retrospectively analyzed 539 consecutive patients with stage I-IV RC who had undergone elective surgery between January 2010 and December 2020, using propensity score-matched analysis. After propensity score matching, we enrolled 200 patients (n = 100 in each groups). Before matching, significant group-dependent differences were observed in terms of age (p = 0.04) and body mass index (p < 0.01). After matching, clinicopathologic outcomes were similar between the groups, but estimated operative time was longer and postoperative lymphorrhea was more frequent in the RARS group. Estimated blood loss, rate of conversion to laparotomy, and incidence of anastomotic leakage or reoperation were significantly lower in the RARS group. No surgical mortality was observed in either group. No significant differences were observed in terms of positive resection margins or number of lymph nodes harvested. RARS was safe and technically feasible, and achieved acceptable short-term outcomes. The robotic technique showed some advantages in RC surgery that require validation in further studies.

Optimizing outcomes of colorectal cancer surgery with robotic platforms

Advanced robotic technology makes it easier to perform total mesorectal excision procedures in the narrow pelvis for rectal cancer while maintaining the advantages of minimally invasive surgery. Robotic surgery for rectal cancer leads to lower conversion rates and faster recovery of urogenital function than conventional laparoscopic surgery. However, longer operative time and high cost are major weaknesses of robotic surgery. To date, most other short-term surgical outcomes, pathologic outcomes, and long-term oncologic outcomes of robotic surgery have not shown significant advantages over laparoscopic surgery. However, robotic surgery is still a valid and highly anticipated surgical approach for rectal cancer because it greatly reduces the surgeon's workload and learning curve. There are also advantages when robotic techniques are applied to technically demanding procedures such as lateral pelvic lymph node dissection or intersphincteric resection. The introduction of new surgical robot systems, including the da Vinci® SP system, is expected to expand the applications of robotic surgery and provide new advantages.

Competency-Based Education in Minimally Invasive and Robotic Colorectal Surgery

Minimally invasive and robotic techniques have become increasingly implemented into surgical practice and are now an essential part of the foundational skills of training colorectal surgeons. Over the past 5 years there has been a shift in the surgical educational paradigm toward competency-based education (CBE). CBE recognizes that trainees learn at different rates but regardless, are required to meet a competent threshold of performance prior to independent practice. Thus, CBE attempts to replace the traditional "time" endpoint of training with "performance." Although conceptually sensible, implementing CBE has proven challenging. This article will define competence, outline appropriate assessment tools to assess technical skill, and review the literature on the number of cases required to achieve competence in colorectal procedures while outlining the barriers to implementing CBE.

How long is the tail end of the learning curve? Results from 1000 consecutive endoscopic endonasal skull base cases following the initial 200 cases

OBJECTIVE

Endoscopic endonasal approaches (EEAs) to the skull base have evolved over the last 20 years to become an essential component of a comprehensive skull base practice. Many case series show a learning curve from the earliest cases, in which the authors were inexperienced or were not using advanced closure techniques. It is generally accepted that once this learning curve is achieved, a plateau is reached with little incremental improvement. Cases performed during the early steep learning curve were eliminated to examine whether the continued improvement exists over the "tail end" of the curve.

METHODS

A prospectively acquired database of all EEA cases performed by the senior authors at Weill Cornell Medicine/NewYork-Presbyterian Hospital was reviewed. The first 200 cases were eliminated and the next 1000 consecutive cases were examined to avoid the bias created by the early learning curve.

RESULTS

Of the 1000 cases, the most common pathologies included pituitary adenoma (51%), meningoencephalocele or CSF leak repair (8.6%), meningioma (8.4%), craniopharyngioma (7.3%), basilar invagination (3.1%), Rathke's cleft cyst (2.8%), and chordoma (2.4%). Use of lumbar drains decreased from the first half to the second half of our series (p <0.05) as did the authors' use of fat alone (p <0.005) or gasket alone (p <0.005) for dural closure, while the use of a nasoseptal flap increased (p <0.005). Although mean tumor diameter was constant (on average), gross-total resection (GTR) increased from 60% in the first half to 73% in the second half (p <0.005). GTR increased for all pathologies but most significantly for chordoma (56% vs 100%, p <0.05), craniopharyngioma (47% vs 0.71%, p <0.05) and pituitary adenoma (67% vs 75%, p <0.05). Hormonal cure for secreting adenomas also increased from 83% in the first half to 89% in the second half (p <0.05). The rate of any complication was unchanged at 6.4% in the first half and 6.2% in the latter half of cases, and vascular injury occurred in only 0.6% of cases. Postoperative CSF leak occurred in 2% of cases and was unchanged between the first and second half of the series.

CONCLUSIONS

This study demonstrates that contrary to popular belief, the surgical learning curve does not plateau but can continue for several years depending on the complexity of the endpoints considered. These findings may have implications for clinical trial design, surgical education, and patient safety measures.

Evolution of Robotic Surgery in a Colorectal Cancer Unit in India

Only a handful of institutions in the country have an established robotic surgery program. Evolution of robotic surgery in the colorectal division, from inception to recent times, is presented here. All the patients undergoing robotic colorectal surgery from the inception of the program (September 2014) to August 2019 were identified. The patient and treatment details and short-term outcomes were collected retrospectively from the prospectively maintained database. The cohort was divided into four chronological groups (group 1 being the oldest) to assess the surgical trends. There were 202 patients. Seventy-one percent were male. Mean BMI was 23.25. Low rectal tumours were most common (47%). A total of 74.3% patients received neo-adjuvant treatment. Multivisceral resection was done in 22 patients, including 4 synchronous liver resections. Average operating time for standard rectal surgery was 280 min with average blood loss of 235 ml. The mean nodal yield was 14. Circumferential resection margin positivity was 6.4%. The mean hospital stay for pelvic exenteration was significantly higher than the rest of the surgeries (except for posterior exenteration and total proctocolectomy) (p = 0.00). Clavin-Dindo grade 3 and 4 complications were seen in 10% patients. As the experience of the team increased, more complex cases were performed. Blood loss, margin positivity, nodal yield, leak rates and complications were evaluated group wise (excluding those with additional procedures) to assess the impact of experience. We did not find any significant change in the parameters studied. With increasing experience, the complexity of surgical procedures performed on da Vinci Xi platform can be increased in a systematic manner. Our short-term outcomes, i.e. nodes harvested, margin positivity, hospital stay and morbidity, are on par with world standards. However, we did not find any significant improvement in these parameters with increasing experience.

Robotic rectal resection: oncologic outcomes

Robotic surgery has progressively gained popularity in the treatment of rectal cancer. However, only a few studies on its oncologic effectiveness are currently present, with contrasting results. The purpose of this study is to report a single surgeon’s experience on robotic rectal resection (RRR) for cancer, focusing on the analysis of oncologic outcomes, both in terms of pathological features and long-term results. One-hundred and twenty-two consecutive patients who underwent RRR for rectal cancer from January 2013 to December 2019 were retrospectively enrolled. Patients’ characteristics and perioperative outcomes were collected. The analyzed oncologic outcomes were pathological features [distal (DM), circumferential margin (CRM) status and quality of mesorectal excision (TME)] and long-term outcomes [overall (OS) and disease-free survival (DFS)]. The mean operative time was 275 (± 60.5) minutes. Conversion rate was 6.6%. Complications occurred in 27 cases (22.1%) and reoperation was needed in 2 patients (1.5%). The median follow-up was 30.5 (5.9–86.1) months. None presented DM positivity. CRM positivity was 2.5% (2 cases) while a complete TME was reached in 94.3% of cases (115 patients). Recurrence rate was 5.7% (2 local, 4 distant and 1 local plus distant tumor relapse). OS and DFS were 90.7% and 83%, respectively. At the multivariate analysis, both CRM positivity and near complete/incomplete TME were recognized as negative prognostic factors for OS and DFS. Under appropriate logistic and operative conditions, robotic surgery for rectal cancer proves to be oncologically effective, with adequate pathological results and long-term outcomes. It also offers acceptable peri-operative outcomes, further confirming the safety and feasibility of the technique.

Impact of laparoscopic surgical experience on the learning curve of robotic rectal cancer surgery

BACKGROUND

Robotic surgery has advantages in terms of the ergonomic design and expectations of shortening the learning curve, which may reduce the number of patients with adverse outcomes during a surgeon's learning period. We investigated the differences in the learning curves of robotic surgery and clinical outcomes for rectal cancer among surgeons with differences in their experiences of laparoscopic rectal cancer surgery.

METHODS

Patients who underwent robotic surgery for colorectal cancer were reviewed retrospectively. Patients were divided into five groups by surgeons, and their clinical outcomes were analyzed. The learning curve of each surgeon with different volumes of laparoscopic experience was analyzed using the cumulative sum technique (CUSUM) for operation times, surgical failure (open conversion or anastomosis-related complications), and local failure (positive resection margins or local recurrence within 1 year).

RESULTS

A total of 662 patients who underwent robotic low anterior resection (LAR) for rectal cancer were included in the analysis. Number of laparoscopic LAR cases performed by surgeon A, B, C, D, and E prior to their first case of robotic surgery were 403, 40, 15, 5, and 0 cases, respectively. Based on CUSUM for operation time, surgeon A, B, C, D, and E's learning curve periods were 110, 39, 114, 55, and 23 cases, respectively. There were no significant differences in the surgical and oncological outcomes after robotic LAR among the surgeons.

CONCLUSIONS

This study demonstrated the limited impact of laparoscopic surgical experience on the learning curve of robotic rectal cancer surgery, which was greater than previously reported curves.

Short-term outcomes of robotic-assisted laparoscopic versus laparoscopic lateral lymph node dissection for advanced lower rectal cancer

BACKGROUND

Therapeutic strategies to suppress local recurrence, including lateral lymph node metastasis, are important to improve the curability of rectal cancer. The aim of the present study was to clarify the advantages of robotic-assisted laparoscopic lateral lymph node dissection (RALLD), comparing its short-term outcomes with those of laparoscopic lateral lymph node dissection (LLLD). There are some retrospective reports comparing RALLD or LLLD and open lateral lymph node dissection (OLLD), but few reports comparing RALLD and LLND to each other.

METHODS

From November 2014 to August 2020, we compared the short-term outcomes in 40 patients who underwent RALLD and 55 patients who underwent LLLD.

RESULTS

The total operative time was significantly longer in the RALLD group than in the LLLD group (p < 0.001). However, lateral dissection time was not significantly different between the groups (p = 0.661). The postoperative hospital time was shorter in the RALLD group than in the LLLD group (p < 0.048). No significant differences were identified in the rates of postoperative bleeding, incisional surgical site infection (SSI), organ/space SSI, urinary disfunction, urinary infection, or small bowel obstruction between the groups. However, anastomotic leakage was significantly lower in the RALLD group than in the LLLD group (p = 0.031).

CONCLUSIONS

The short-term outcomes of RALLD indicate it is feasible, and RALLD may be a useful modality for lower rectal cancer.

The slope of the learning curve in 600 consecutive endoscopic transsphenoidal pituitary surgeries

BACKGROUND

Endonasal endoscopic transsphenoidal surgery (EETS) for pituitary adenoma has become a mainstay of treatment over the last two decades and it is generally accepted that once this learning curve is achieved, a plateau is reached with little incremental improvement.

OBJECTIVE

The objective of this study was to assess the slope of the learning curve over a long period of time for a variety of outcomes measures.

METHODS

We examined outcomes and complications in a consecutive series of 600 EETS for pituitary adenoma grouped into quartiles based on date of surgery.

RESULTS

GTR significantly increased across quartiles from 55 to 79% in the last quartile (p < 0.005). The rate of intraoperative CSF leak significantly decreased from 60% in the first quartile to 33% in the last quartile and the rate of lumbar drain placement from 28% in the first quartile to 6% in the last quartile (p < 0.005). Hormonal remission for secreting adenomas increased from 68% in the first quartile to 90% in the last quartile (p < 0.05). The rate of post-operative CSF leak trended lower (3% in first quartile to 0.7% in last two quartiles). The greatest improvement in outcome occurred between the first and second quartiles (19.9%), but persistent improvement occurred between the second and third (6.7%) and third and fourth quartiles (8.0%).

CONCLUSION

Although the slope of the learning curve is steeper earlier in a surgeon's experience, the slope does not plateau and continues to increase even over more than a decade.

Safety and Feasibility of Robotic Natural Orifice Specimen Extraction Surgery in Colorectal Neoplasms During the Initial Learning Curve

Aim: To analyze the learning curve (LC) for robotic natural orifice specimen extraction surgery (NOSES) for colorectal neoplasms and evaluate safety and feasibility during the initial LC.

Method: Patients who consecutively underwent robotic NOSES performed by two surgeons between March 2016 and October 2019 were analyzed retrospectively. The operation time was evaluated using the cumulative sum method to analyze the LC. The clinicopathological data before and after the completion of LC were extracted and compared to evaluate safety and feasibility.

Results: In total, 99 and 66 cases were scheduled for robotic NOSES by Prof. Yao and Prof. Li, respectively. The peak points of LC were observed at the 42nd and 15th cases of Yao and Li, respectively, then operation time began to decrease. Only the operation time for Yao before the completion of LC (213.3 ± 67.0 min) was longer than that after the completion of LC (143.8 ± 33.3 min). For Yao nor for Li, other indices, such as postoperative hospital stay, intraoperative blood loss, conversion to laparotomy, incidence of anastomotic leakage, reoperation rate, and 90-day mortality rate lacked significant statistical differences(P > 0.05). In terms of feasibility, the number of lymph nodes harvested, positive resection margin rate, and total cost before and after the completion of LC had no significant statistical difference (P > 0.05).

Conclusion: The cases before the completion of LC for robotic NOSES in colorectal neoplasms varied from 15 cases to 42 cases. Robotic NOSES is safe and feasible during the initial LC.

Impact of robotic learning curve on histopathology in rectal cancer: A pooled analysis

BACKGROUND

A beneficial impact of robotic proctectomy on circumferential resection margin (CRM) is expected due to the robot's articulating instruments in the pelvis. There are however concerns about a negative impact on the quality of total mesorectal excision (TME) due to the lack of tactile feedback. The aim of this study was to assess whether surgeons' learning curve impacted CRM and TME quality.

METHODS

In a multicenter study, individual patient data of robotic proctectomy for resectable rectal cancer were pooled. Patients were stratified into two phases of surgeons' learning curve. Cumulative sum (CUSUM) analysis was used to determine the transition from learning phase (LP) to plateau phase (PP), which were compared. CRM was microscopically measured in mm by pathologists. TME quality was classified by pathologists as complete, nearly complete or incomplete. T-test and Chi-squared tests were used to compare continuous and categorical variables, respectively.

RESULTS

235 patients underwent robotic proctectomy by five surgeons. 83 LP patients were comparable to 152 PP patients for age (p = 0.20), gender (67.5% vs. 65.1% males; p = 0.72), BMI (p = 0.82), cancer stage (p = 0.36), neoadjuvant chemoradiation (p = 0.13), distance of tumor from anal verge (5.8 ± 4.4 vs. 5.5 ± 3.3; p = 0.56). CRM did not differ (7.7 ± 11.4 mm vs. 8.4 ± 10.3 mm; p = 0.62). The rate of complete TME quality was significantly improved in PP patients as compared to LP patients (73.5% vs. 92.1%; p < 0.001).

CONCLUSION

While learning had no impact on circumferential resection margins, the quality of TME significantly improved during surgeons' plateau phase as compared to their learning phase.

Learning curve in robotic colorectal surgery

With the rapid adoption of robotics in colorectal surgery, there has been growing interest in the pace at which surgeons gain competency, as it may aid in self-assessment or credentialing. Therefore, we sought to evaluate the learning curve of an expert laparoscopic colorectal surgeon who performed a variety of colorectal procedures robotically. This is a retrospective review of a prospective database of 111 subsequent colorectal procedures performed by a single colorectal surgeon. The cumulative summation technique (CUSUM) was used to construct a learning curve for robotic proficiency by analyzing total operative and console times. Postoperative outcomes including length of stay, 30-day complications, and 30-day readmission rates were evaluated. Chi-square and one-way ANOVA (including Kruskal-Wallis) tests were used to evaluate categorical and continuous variables. Our patient cohort had a mean age of 62.4, mean BMI of 26.9, and mean ASA score of 2.41. There were two conversions to open surgery. The CUSUM graph for console time indicated an initial decrease at case 13 and another decrease at case 83, generating 3 distinct performance phases: learning (n = 13), competence (n = 70), and mastery (n = 28). An interphase comparison revealed no significant differences in age, gender, BMI, ASA score, types of procedures, or indications for surgery between the three phases. Over the course of the study, both mean surgeon console time and median length of stay decreased significantly (p = 0.00017 and p = 0.016, respectively). Although statistically insignificant, there was a downward trend in total operative time and postoperative complication rates. Learning curves for robotic colorectal surgery are commonly divided into three performance phases. Our findings contribute to the construction of a reliable learning curve for the transition of colorectal surgeons to robotics. Furthermore, they may help guide the stepwise training and credentialing of new robotic surgeons.

Trends in utilization, conversion rates, and outcomes for minimally invasive approaches to non-metastatic rectal cancer: a national cancer database analysis

BACKGROUND

This study examined utilization and conversion rates for robotic and laparoscopic approaches to non-metastatic rectal cancer. Secondary aims were to examine short- and long-term outcomes of patients who underwent conversion to laparotomy from each approach.

METHODS

The National Cancer Database (NCDB) was reviewed for all cases of non-metastatic adenocarcinoma of the rectum or rectosigmoid junction who underwent surgical resection from 2010 to 2016. Utilization rates of robotic, laparoscopic, and open approaches were examined. Patients were split into cohorts by approach. Subgroup analyses were performed by primary tumor site and surgical procedure. Multivariable analysis was performed by multivariable logistic regression for binary outcomes and multivariable general linear models for continuous outcomes. Survival analysis was performed by Kaplan-Meier and multivariable cox-proportional hazards regression.

RESULTS

From 2010 to 2016, there was a statistically significant increase in utilization of the robotic and laparoscopic approaches over the study period and a statistically significant decrease in utilization of the open approach. The conversion rates for robotic and laparoscopic cohorts were 7.0% and 15.7%, p < 0.0001. Subgroup analysis revealed statistically lower conversion rates between robotic and laparoscopic approaches for rectosigmoid and rectal tumors and for LAR and APR. Converted cohorts had statistically significant higher odds of short term mortality than the non-converted cohorts (p  < 0.05).Laparoscopic conversion had statistically higher odds of positive margins (p  < 0.0001) and 30-day unplanned readmission (p  < 0.0001) than the laparoscopic non-conversion. Increased adjusted mortality hazard was seen for converted laparoscopy relative to non-converted laparoscopy (p  = 0.0019).

CONCLUSION

From 2010 to 2016, there was a significant increase in utilization of minimally invasive approaches to surgical management of non-metastatic rectal cancer. A robotic approach demonstrated decreased conversion rates than a laparoscopic approach at the rectosigmoid junction and rectum and for LAR and APR. Improved outcomes were seen in the minimally invasive cohorts compared to those that converted to laparotomy.

Robotic sphincter saving rectal cancer surgery: A learning curve analysis

BACKGROUND

Longer operation time is one of the major obstacles in front of the proposed benefits of robotic rectal surgery. We intended to evaluate the learning process for robotic surgery in sphincter saving rectal cancer surgery.

METHODS

The learning curve was evaluated using the cumulative sum (CUSUM) method. The variable evaluated for learning curve calculation was the operative time.

RESULTS

The learning curve was divided into two phases: initial 52 operations comprised phase 1 and the following 44 operations represented phase 2. Interphase comparisons showed that phase 2 patients had shorter operation times (323.3 ± 102.8 vs. 379.9 ± 108.7 min, p = 0.011), less blood loss (37.2 ± 51.0 vs. 87.7 ± 124.8 mL, p = 0.009), longer distal resection margins (4.5 ± 4.3 vs. 2.5 ± 1.7 cm, p = 0.008), and higher rates of grade 3 mesorectal completeness (p = 0.001).

CONCLUSION

In this study, we saw that the cut-off level in the learning curve of a laparoscopically experienced surgeon could be beyond the numbers reported in the literature.

Can better surgical outcomes be obtained in the learning process of robotic rectal cancer surgery? A propensity score-matched comparison between learning phases

BACKGROUND

Although studies of robotic rectal cancer surgery have demonstrated the effects of learning on operation time, comparisons have failed to demonstrate differences in clinicopathological outcomes between unadjusted learning phases. This study aimed to investigate the learning curve of robotic rectal cancer surgery for clinicopathological outcomes and compare surgical outcomes between adjusted learning phases. Study design We enrolled 506 consecutive patients with rectal adenocarcinoma who underwent robotic resection by a single surgeon between 2007 and 2018. Risk-adjusted cumulative sum (RA-CUSUM) for surgical failure was used to analyze the learning curve. Surgical failure was defined as the occurrence of any of the following: conversion to open surgery, severe complications (Clavien-Dindo grade ≥ 3a), insufficient number of harvested lymph nodes (LNs), or R1 resection. Comparisons between learning phases analyzed by RA-CUSUM were performed before and after propensity score matching.

RESULTS

In RA-CUSUM analysis, the learning curve was divided into two learning phases: phase 1 (1st-177th cases, n = 177) and phase 2 (178th-506th cases, n = 329). Before matching, patients in phase 2 had deeper tumor invasion and higher rates of positive LNs on pretreatment images and preoperative chemoradiotherapy. After matching, phase 1 (n = 150) and phase 2 (n = 150) patients exhibited similar clinical characteristics. Phase 2 patients had lower rates of surgical failure overall and these components: conversion to open surgery, severe complications, and insufficient harvested LNs.

CONCLUSIONS

For robotic rectal cancer surgery, surgical outcomes improved after the 177th case. Further studies by other robotic surgeons are required to validate our results.

Robotic Surgery for Rectal Cancer and Cost-Effectiveness

Robotic surgery is considered as one of the advanced treatment modality of minimally invasive surgery for rectal cancer. Robotic rectal surgery has been performed for three decades and its application is gradually expanding along with technology development. It has several technical advantages which include magnified three-dimensional vision, better ergonomics, multiple articulated robotic instruments, and the opportunity to perform remote surgery. The technical benefits of robotic system can help to manipulate more meticulously during technical challenging procedures including total mesorectal excision in narrow pelvis, lateral pelvic node dissection, and intersphincteric resection. It is also reported that robotic rectal surgery have been shown more favorable postoperative functional outcomes. Despite its technical benefits, a majority of studies have been reported that there is rarely clinical or oncologic superiority of robotic surgery for rectal cancer compared to conventional laparoscopic surgery. In addition, robotic rectal surgery showed significantly higher costs than the standard method. Hence, the cost-effectiveness of robotic rectal surgery is still questionable. In order for robotic rectal surgery to further develop in the field of minimally invasive surgery, there should be an obvious cost-effective advantages over laparoscopic surgery, and it is crucial that large-scale prospective randomized trials are required. Positive competition of industries in correlation with technological development may gradually reduce the price of the robotic system, and it will be helpful to increase the cost-effectiveness of robotic rectal surgery.

Incorporating a Detailed Case Log System to Standardize Robotic Colon and Rectal Surgery Resident Training and Performance Evaluation

OBJECTIVE

This study was designed to evaluate a novel case log used as part of a standardized robotic colon and rectal surgery resident training program.

DESIGN

This observational study describes a detailed procedure log developed to standardize training of residents in robotic colorectal surgery. The procedure log tracks resident total case numbers and execution of specific steps of eleven colorectal procedures. Case log data were accumulated and analyzed to assess resident progress.

SETTING/PARTICIPANTS

The study includes colon and rectal surgery residents during the 2016-2017 academic year. The national Colon and Rectal Surgery Robotic Training Program was developed and implemented during the 2010-2011 academic year in response to increasing adoption of robotic-assisted colorectal surgery. This program evolved to include online modules, dry lab exercises, simulation and cadaveric courses.

RESULTS

Forty of 93 residents in 54 colon and rectal surgery programs participated in the case log system and the comprehensive training program. Residents participated as console surgeon in an average of 28 cases (range 1-115). Sixty-five percent of participating residents performed ≥20 complex colorectal cases as console surgeon. Of the 1080 operations entered, the three most frequently performed procedures were low anterior resections (n = 360, 33.3%), sigmoid resections (n = 172, 15.9%), and right colectomies with intracorporeal anastomosis (n = 138, 12.8%). Residents with 10 or more robotic cases had a 27% increase in cases as console surgeon and a 28% decrease in cases completed as bedside assistant. Experience and progression to the console varied by resident and by program.

CONCLUSION

This detailed standardized case log system provides comprehensive assessment of resident experience that allows preparation for a robotic colon and rectal surgery practice after fellowship. As adoption of the robotic approach for colon and rectal cases continues to increase, novel methods that evaluate teaching methods and resident progress warrant further study.

The first year is the hardest: a comparison of early versus late experience after the introduction of robotic hiatal hernia repair

While the majority of the literature written concerning minimally invasive hiatal hernia repair involves laparoscopy, little has been written concerning the transition to a robotic technique. We present our experience, with a transparent analysis of data, with regard to the introduction of robotic paraesophageal hernia (PEH) repair by an experienced laparoscopic surgeon. We reviewed our first 30 consecutive patients who underwent robotic PEH over a 2-year period after the introduction of robotic surgery at our institution. Patients were divided into two groups: the early experience group (procedures performed within the first year of introduction of robotic technique, n = 13) and a late experience group (procedures performed in the second year, n = 17). All procedures were performed by a single experienced foregut surgeon. The mean operative time for the early group was significantly greater than for the late group, 184 min versus 142 min, respectively (p < 0.01). Four patients in the early group required conversion to open, while zero patients in the late group required conversion (p = 0.03). Patient demographics and complications did not differ significantly between the two patient populations. The early robotic hiatal hernia repair experience can be more difficult than expected, even in the hands of an experienced laparoscopic team. We identify several areas of improvement including patient positioning, operating room team training, and technical experience. This data can help other surgeons prepare for the transition to robotic foregut surgery.

Open versus minimally invasive surgery for rectal cancer: a single-center cohort study on 237 consecutive patients

Minimally invasive surgery (MIS) is gaining popularity in rectal tumor treatment. However, contrasting data are available regarding its safety and efficacy. Our aim is to compare the open and MIS approaches for rectal cancer treatment. Two-hundred-thirty-seven patients were included: 113 open and 124 MIS rectal resections. After the propensity score matching analysis (PS), the cases were matched into 42 open and 42 MIS. Short- and long-term outcomes, and pathological findings were analyzed before and after PS. A further comparison of the same outcomes and costs was conducted between the laparoscopic and the robotic approaches. As a whole, a sphincter-preserving procedure was more frequently performed in the MIS group (110 vs 75 cases; p < 0.0001). The estimated blood loss during MIS was significantly lower than during open surgery [127 (± 92) vs 242 (± 122) mL; p < 0.0001], with clear advantages for the robotic approach over laparoscopy [113 (± 87) vs 147 (± 93) mL; p 0.01]. Complication rate was comparable between the two groups. A higher rate of CRM positivity was evidenced after open surgery (12.4% vs 1.7%; p 0.004). A higher number of lymph nodes was harvested in the MIS group [12.5 (± 6.4) vs 11 (± 5.6); p 0.04]. After PS, no difference in terms of perioperative outcomes was noted, with the only exception of a higher blood loss in the open approach [242 (± 122) vs 127 (± 92) mL; p < 0.0001]. For the matched cases, no difference in 5-year overall and disease-free survival was evidenced (p 0.50 and 0.88, respectively). Mean costs were higher for robotics as compared to laparoscopy [9812 (±1974)€ vs 9045 (± 1893)€; p 0.02]. MIS could be considered as a treatment option for rectal cancer. The PS study evidenced clear advantages in terms of estimated blood loss over the open surgery. Costs still remain the main limit for robotics.

Robotic-assisted surgery for rectal cancer: Current state and future perspective

Interest in minimally invasive surgery has increased in recent decades. Robotic-assisted laparoscopic surgery (RALS) was introduced as the latest advance in minimally invasive surgery. RALS has the potential to provide better clinical outcomes in rectal cancer surgery, allowing for precise dissection in the narrow pelvic space. In addition, RALS represents an important advancement in surgical education with respect to use of the dual-console robotic surgery system. Because the public health insurance systems in Japan have covered the cost of RALS for rectal cancer since April 2018, RALS has been attracting increasingly more attention. Although no overall robust evidence has yet shown that RALS is superior to laparoscopic or open surgery, the current evidence supports the notion that technically demanding subgroups (patients with obesity, male patients, and patients treated by extended procedures) may benefit from RALS. Technological innovation is a constantly evolving field. Several companies have been developing new robotic systems that incorporate new technology. This competition among companies in the development of such systems is anticipated to lead to further improvements in patient outcomes as well as drive down the cost of RALS, which is one main concern of this new technique.

Learning Curve of Robotic Rectal Surgery With Lateral Lymph Node Dissection: Cumulative Sum and Multiple Regression Analyses

OBJECTIVE

This study aimed to assess the learning curve of robotic rectal surgery, a procedure that has gained increasing focus in recent years because it is expected that the advanced devices used in this approach provide advantages resulting in a shorter learning curve than that of laparoscopic surgery. However, no studies have assessed the learning curve of robotic rectal surgery, especially when lateral lymph node dissection is required.

DESIGN

This was a nonrandomized, retrospective study from a single institution.

SETTING

All consecutive patients who underwent robotic rectal or sigmoid colon surgery by a single surgeon between February 2012 and July 2016 in the University of Tokyo Hospital were enrolled. The learning curve for console time was assessed using a cumulative sum analysis and multiple linear regression analysis.

PARTICIPANTS

A total of 131 consecutive patients underwent robotic rectal or sigmoid colon surgery performed by a single experienced surgeon. Of these, 41 patients received lateral lymph node dissection.

RESULTS

A cumulative sum plot for console time demonstrated that the learning period could be divided into 3 phases: Phase I, Cases 1 to 19; Phase II, Cases 20 to 78; and Phase III, Cases 79 to 131. Multiple linear regression analysis indicated that console time decreased significantly from one phase to another (Phase I-II, Δconsole time 83.0 minutes; Phase II-III, Δconsole time 40.1 minutes). Other factors affecting console time included body mass index, operative procedure, and lateral lymph node dissection, but not neoadjuvant therapy (such as chemoradiotherapy) or depth of invasion. Lateral lymph node dissection required an additional 138.4 minutes.

CONCLUSIONS

Our findings suggest that the first phase of the learning curve consists of the first 19 cases, which seems sufficient to master the manipulation of robotic arms and to understand spatial relationships unique to the robotic procedure.

Robotic Right Colectomy for Colon Cancer: Comparison of Outcomes from a Single Institution with the ACS-NSQIP Database

BACKGROUND

Robotic surgery has increased in recent years for the treatment of colorectal cancer; however, it is not yet the standard of care. This study aims to compare the 30-day outcomes after robotic colectomy for right-sided colon cancer from our institution with those from a national dataset, the targeted colectomy American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.

METHODS

Patients undergoing elective, robotic, right colon resection for stage I, II, and III colon cancer were identified within the targeted colectomy ACS-NSQIP database from 2012 to 2014. Patients meeting the same criteria were identified within a prospectively maintained institutional database from 2009 to 2015. Univariate analyses using chi-square tests and Student's t-tests were done where appropriate to compare baseline characteristics and outcomes between the two groups.

RESULTS

Patients at our institution had a significantly higher average number of lymph nodes retrieved (24.4 versus 20.1, P = .046). There was no statistically significant difference between the two groups regarding the incidence of wound infections, anastomotic leaks, blood transfusions, unplanned return to the operating room, or prolonged length of hospital stay. There were no 30-day mortalities at our institution and only one in the ACS-NSQIP database.

CONCLUSIONS

Our institutional experience with robotic right colon resection is equivalent to that of a national sample. This study demonstrates the safety of performing robotic right hemicolectomy for the treatment of colon cancer.