Initial experience with robotic hepatectomy in Singapore: analysis of 48 resections in 43 consecutive patients

Feasibility and safety of robotic liver resection for huge (≥10 cm) hepatocellular carcinoma in a single centre: A propensity score-matched single-surgeon study

BACKGROUND

The applicability of robot-assisted resection for huge hepatocellular carcinoma (HCC) of ≥10 cm remains contentious with limited available data.

METHODS

This retrospective analysis involved 337 patients who underwent robotic liver resection for HCC by a single surgeon. Propensity score matching (PSM) was employed to compare perioperative indicators between patients with regular and huge HCC.

RESULTS

The regular HCC group exhibited a shorter median operative duration than the huge HCC group. The IWATE criteria revealed higher scores in the huge HCC group than in the regular HCC group. No significant differences were observed between the two groups in Pringle time, drainage tube removal, duration of hospital stays, blood loss volume, blood product transfusion, margin status, conversion rate to open surgery, bile leakage, in-hospital mortality, and reoperation rate.

CONCLUSION

Robotic liver resection is feasible for huge HCC, with effective perioperative risk management potentially improving outcomes for subsequent minimally invasive surgeries.

Propensity-score Matched and Coarsened-exact Matched Analysis Comparing Robotic and Laparoscopic Major Hepatectomies: An International Multicenter Study of 4822 Cases

OBJECTIVE

To compare the outcomes between robotic major hepatectomy (R-MH) and laparoscopic major hepatectomy (L-MH).

BACKGROUND

Robotic techniques may overcome the limitations of laparoscopic liver resection. However, it is unknown whether R-MH is superior to L-MH.

METHODS

This is a post hoc analysis of a multicenter database of patients undergoing R-MH or L-MH at 59 international centers from 2008 to 2021. Data on patient demographics, center experience volume, perioperative outcomes, and tumor characteristics were collected and analyzed. Both 1:1 propensity-score matched (PSM) and coarsened-exact matched (CEM) analyses were performed to minimize selection bias between both groups.

RESULTS

A total of 4822 cases met the study criteria, of which 892 underwent R-MH and 3930 underwent L-MH. Both 1:1 PSM (841 R-MH vs. 841 L-MH) and CEM (237 R-MH vs. 356 L-MH) were performed. R-MH was associated with significantly less blood loss {PSM:200.0 [interquartile range (IQR):100.0, 450.0] vs 300.0 (IQR:150.0, 500.0) mL; P = 0.012; CEM:170.0 (IQR: 90.0, 400.0) vs 200.0 (IQR:100.0, 400.0) mL; P = 0.006}, lower rates of Pringle maneuver application (PSM: 47.1% vs 63.0%; P < 0.001; CEM: 54.0% vs 65.0%; P = 0.007) and open conversion (PSM: 5.1% vs 11.9%; P < 0.001; CEM: 5.5% vs 10.4%, P = 0.04) compared with L-MH. On subset analysis of 1273 patients with cirrhosis, R-MH was associated with a lower postoperative morbidity rate (PSM: 19.5% vs 29.9%; P = 0.02; CEM 10.4% vs 25.5%; P = 0.02) and shorter postoperative stay [PSM: 6.9 (IQR: 5.0, 9.0) days vs 8.0 (IQR: 6.0 11.3) days; P < 0.001; CEM 7.0 (IQR: 5.0, 9.0) days vs 7.0 (IQR: 6.0, 10.0) days; P = 0.047].

CONCLUSIONS

This international multicenter study demonstrated that R-MH was comparable to L-MH in safety and was associated with reduced blood loss, lower rates of Pringle maneuver application, and conversion to open surgery.

Limited liver resections in the posterosuperior segments: international multicentre propensity score-matched and coarsened exact-matched analysis comparing the laparoscopic and robotic approaches

Background

Limited liver resections (LLRs) for tumours located in the posterosuperior segments of the liver are technically demanding procedures. This study compared outcomes of robotic (R) and laparoscopic (L) LLR for tumours located in the posterosuperior liver segments (IV, VII, and VIII).

Methods

This was an international multicentre retrospective analysis of patients who underwent R-LLR or L-LLR at 24 centres between 2010 and 2019. Patient demographics, perioperative parameters, and postoperative outcomes were analysed; 1 : 3 propensity score matching (PSM) and 1 : 1 coarsened exact matching (CEM) were performed.

Results

Of 1566 patients undergoing R-LLR and L-LLR, 983 met the study inclusion criteria. Before matching, 159 R-LLRs and 824 L-LLRs were included. After 1 : 3 PSM of 127 R-LLRs and 381 L-LLRs, comparison of perioperative outcomes showed that median blood loss (100 (i.q.r. 40–200) versus 200 (100–500) ml; P = 0.003), blood loss of at least 500 ml (9 (7.4 per cent) versus 94 (27.6 per cent); P &lt; 0.001), intraoperative blood transfusion rate (4 (3.1 per cent) versus 38 (10.0 per cent); P = 0.025), rate of conversion to open surgery (1 (0.8 per cent) versus 30 (7.9 per cent); P = 0.022), median duration of Pringle manoeuvre when applied (30 (20–46) versus 40 (25–58) min; P = 0.012), and median duration of operation (175 (130–255) versus 224 (155–300); P &lt; 0.001) were lower in the R-LLR group compared with the L-LLR group. After 1 : 1 CEM of 104 R-LLRs with 104 L-LLRs, R-LLR was similarly associated with significantly reduced blood loss and a lower rate of conversion to open surgery.

Conclusion

Based on a matched analysis of well selected patients, both robotic and laparoscopic access could be undertaken safely with good outcomes for tumours in the posterosuperior liver segments.

Robotic vs. laparoscopic liver surgery: a single-center analysis of 600 consecutive patients in 6 years

Background

While laparoscopic liver surgery has become a standard procedure, experience with robotic liver surgery is still limited. The aim of this prospective study was to evaluate safety and feasibility of robotic liver surgery and compare outcomes with conventional laparoscopy.

Methods

We here report the results of a single-center, prospective, post-marketing observational study (DRKS00017229) investigating the safety and feasibility of robotic liver surgery. Baseline characteristics, surgical complexity (using the IWATE score), and postoperative outcomes were then compared to laparoscopic liver resections performed at our center between January 2015 and December 2020. A propensity score-based matching (PSM) was applied to control for selection bias.

Results

One hundred twenty nine robotic liver resections were performed using the da Vinci Xi surgical system (Intuitive) in this prospective study and were compared to 471 consecutive laparoscopic liver resections. After PSM, both groups comprised 129 cases with similar baseline characteristics and surgical complexity. There were no significant differences in intraoperative variables, such as need for red blood cell transfusion, duration of surgery, or conversion to open surgery. Postoperative complications were comparable after robotic and laparoscopic surgery (Clavien–Dindo ≥ 3a: 23% vs. 19%, p = 0.625); however, there were more bile leakages grade B–C in the robotic group (17% vs. 7%, p = 0.006). Length of stay and oncological short-term outcomes were comparable.

Conclusions

We propose robotic liver resection as a safe and feasible alternative to established laparoscopic techniques. The object of future studies must be to define interventions where robotic techniques are superior to conventional laparoscopy.

Minimally Invasive vs Open Major Hepatectomies for Liver Malignancies: a Propensity Score-Matched Analysis

BACKGROUND

The majority of evidence with regards to minimally invasive liver resection (MILR) favors its application in minor hepatectomies. We conducted a propensity score-matched (PSM) analysis to determine its feasibility and safety in major hepatectomies (MIMH) for liver malignancies.

METHODS

Retrospective review of 130 patients who underwent MIMH and 490 patients who underwent open major hepatectomy (OMH) for malignant pathologies was performed. PSM in a 1:1 ratio identified two groups of patients with similar baseline clinicopathological characteristics. Perioperative outcomes were then compared. Major hepatectomies included traditional major (>3 segments) and technical major hepatectomies (right anterior and right posterior sectionectomies).

RESULTS

Both cohorts were well-matched for baseline characteristics after PSM. Of 130 MIMH cases, there were 12 conversions to open. Comparison of perioperative outcomes demonstrated a significant association of MIMH with longer operation time and more frequent application of Pringle's maneuver (PM), but decreased postoperative stay. These results were consistent on a subgroup analysis that only included patients undergoing traditional major hepatectomies. A second subgroup analysis restricted to cirrhotic patients demonstrated that while perioperative outcomes were equivalent, MIMH was similarly associated with a longer operative time. Subset analyses of resections performed after 2015 demonstrated that MIMH was additionally associated with a lower postoperative morbidity compared to OMH.

CONCLUSION

Comparison of perioperative and short-term oncological outcomes between MIMH and OMH for malignancies demonstrated that MIMH is feasible and safe. It is associated with a shorter hospital stay at the expense of a longer operation time compared to OMH.

An international multicenter propensity-score matched and coarsened-exact matched analysis comparing between robotic versus laparoscopic partial liver resections of the anterolateral segments

BACKGROUND

Robotic liver resections RLR may have the ability to address some of the drawbacks of laparoscopic(L)LR but few studies have done a head-to-head comparison of the outcomes after anterolateral segment resections by the two techniques.

METHODS

A retrospective study was conducted of 3202 patients who underwent minimally-invasive LR of the anterolateral liver segments at 26 international centres from 2005 to 2020. 2606 cases met study criteria of which there were 358 RLR and 1868 LLR. Peri-operative outcomes were compared between the two groups using a 1:3 Propensity Score Matched(PSM) and 1:1 Coarsened Exact Matched(CEM) analysis.

RESULTS

Patients matched after 1:3 PSM(261 RLR vs. 783 LLR) and 1:1 CEM(296 RLR vs. 296 LLR) revealed no significant differences in length of stay, readmission rates, morbidity, mortality and involvement of or close oncological margins. RLR surgeries were associated with significantly less blood loss(50ml vs. 100ml, p<0.001) and lower rates of open conversion on both PSM(1.5% vs. 6.8%, p=0.003) and CEM(1.4% vs. 6.4%, p=0.004) compared to LLR. Though PSM analysis showed RLR to have a longer operating time than LLR(170 min vs. 160 min, p=0.036), this difference proved to be insignificant on CEM(167 min vs. 163 min. p=0.575).

CONCLUSION

This multicentre international combined PSM and CEM study showed that both RLR and LLR have equivalent perioperative outcomes when performed in selected patients at high volume centres. The robotic approach was associated with significantly lower blood loss and allowed more surgeries to be completed in a minimally-invasive fashion.

Short-term outcomes of robotic liver resection: An initial single-institution experience

BACKGROUND

Liver surgery has traditionally been characterized by the complexity of its procedures and potentially high rates of morbidity and mortality in inexperienced hands. The robotic approach has gradually been introduced in liver surgery and has increased notably in recent years. However, few centers currently perform robotic liver surgery and experiences in robot-assisted surgical procedures continue to be limited compared to the laparoscopic approach.

AIM

To analyze the outcomes and feasibility of an initial robotic liver program implemented in an experienced laparoscopic hepatobiliary center.

METHODS

A total of forty consecutive patients underwent robotic liver resection (da Vinci Xi, intuitive.com, United States) between June 2019 and January 2021. Patients were prospectively followed and retrospectively reviewed. Clinicopathological characteristics and perioperative and short-term outcomes were analyzed. Data are expressed as mean and standard deviation. The study was approved by the Institutional Review Board.

RESULTS

The mean age of patients was 59.55 years, of which 18 (45%) were female. The mean body mass index was 29.41 kg/m². Nine patients (22.5%) were cirrhotic. Patients were divided by type of resection as follows: Ten segmentectomies, three wedge resections, ten left lateral sectionectomies, six bisegmentectomies (two V-VI bisegmentectomies and four IVb-V bisegmentectomies), two right anterior sectionectomies, five left hepatectomies and two right hepatectomies. Malignant lesions occurred in twenty-nine (72.5%) of the patients. The mean operative time was 258.11 min and two patients were transfused intraoperatively (5%). Inflow occlusion was used in thirty cases (75%) and the mean total clamping time was 32.62 min. There was a single conversion due to uncontrollable hemorrhage. Major postoperative complications (Clavien–Dindo > IIIb) occurred in three patients (7.5%) and mortality in one (2.5%). No patient required readmission to the hospital. The mean hospital stay was 5.6 d.

CONCLUSION

Although robotic hepatectomy is a safe and feasible procedure with favorable short-term outcomes, it involves a demanding learning curve that requires a high level of training, skill and dexterity.

International multicentre propensity score-matched analysis comparing robotic versus laparoscopic right posterior sectionectomy

BACKGROUND

Minimally invasive right posterior sectionectomy (RPS) is a technically challenging procedure. This study was designed to determine outcomes following robotic RPS (R-RPS) and laparoscopic RPS (L-RPS).

METHODS

An international multicentre retrospective analysis of patients undergoing R-RPS versus those who had purely L-RPS at 21 centres from 2010 to 2019 was performed. Patient demographics, perioperative parameters, and postoperative outcomes were analysed retrospectively from a central database. Propensity score matching (PSM) was performed, with analysis of 1 : 2 and 1 : 1 matched cohorts.

RESULTS

Three-hundred and forty patients, including 96 who underwent R-RPS and 244 who had L-RPS, met the study criteria and were included. The median operating time was 295 minutes and there were 25 (7.4 per cent) open conversions. Ninety-seven (28.5 per cent) patients had cirrhosis and 56 (16.5 per cent) patients required blood transfusion. Overall postoperative morbidity rate was 22.1 per cent and major morbidity rate was 6.8 per cent. The median postoperative stay was 6 days. After 1 : 1 matching of 88 R-RPS and L-RPS patients, median (i.q.r.) blood loss (200 (100-400) versus 450 (200-900) ml, respectively; P < 0.001), major blood loss (> 500 ml; P = 0.001), need for intraoperative blood transfusion (10.2 versus 23.9 per cent, respectively; P = 0.014), and open conversion rate (2.3 versus 11.4 per cent, respectively; P = 0.016) were lower in the R-RPS group. Similar results were found in the 1 : 2 matched groups (66 R-RPS versus 132 L-RPS patients).

CONCLUSION

R-RPS and L-RPS can be performed in expert centres with good outcomes in well selected patients. R-RPS was associated with reduced blood loss and lower open conversion rates than L-RPS.

Three-Device (3D) Technique for Liver Parenchyma Dissection in Robotic Liver Surgery

Background: The implementation of robotics in liver surgery offers several advantages compared to conventional open and laparoscopic techniques. One major advantage is the enhanced degree of freedom at the tip of the robotic tools compared to laparoscopic instruments. This enables excellent vessel control during inflow and outflow dissection of the liver. Parenchymal transection remains the most challenging part during robotic liver resection because currently available robotic instruments for parenchymal transection have several limitations and there is no standardized technique as of yet. We established a new strategy and share our experience. Methods: We present a novel technique for the transection of liver parenchyma during robotic surgery, using three devices (3D) simultaneously: monopolar scissors and bipolar Maryland forceps of the robot and laparoscopic-guided waterjet. We collected the perioperative data of twenty-eight patients who underwent this procedure for minor and major liver resections between February 2019 and December 2020 from the Magdeburg Registry of minimally invasive liver surgery (MD-MILS). Results: Twenty-eight patients underwent robotic-assisted 3D parenchyma dissection within the investigation period. Twelve cases of major and sixteen cases of minor hepatectomy for malignant and non-malignant cases were performed. Operative time for major liver resections (≥ 3 liver segments) was 381.7 (SD 80.6) min vs. 252.0 (70.4) min for minor resections (p < 0.01). Intraoperative measured blood loss was 495.8 (SD 508.8) ml for major and 256.3 (170.2) ml for minor liver resections (p = 0.090). The mean postoperative stay was 13.3 (SD 11.1) days for all cases. Liver surgery-related morbidity was 10.7%, no mortalities occurred. We achieved an R0 resection in all malignant cases. Conclusions: The 3D technique for parenchyma dissection in robotic liver surgery is a safe and feasible procedure. This novel method offers an advanced locally controlled preparation of intrahepatic vessels and bile ducts. The combination of precise extrahepatic vessel handling with the 3D technique of parenchyma dissection is a fundamental step forward to the standardization of robotic liver surgery for teaching purposing and the wider adoption of robotic hepatectomy into routine patient care.

Minimally invasive liver resection for huge (≥10 cm) tumors: an international multicenter matched cohort study with regression discontinuity analyses

Background

The application and feasibility of minimally invasive liver resection (MILR) for huge liver tumours (≥10 cm) has not been well documented.

Methods

Retrospective analysis of data on 6,617 patients who had MILR for liver tumours were gathered from 21 international centers between 2009-2019. Huge tumors and large tumors were defined as tumors with a size ≥10.0 cm and 3.0-9.9 cm based on histology, respectively. 1:1 coarsened exact-matching (CEM) and 1:2 Mahalanobis distance-matching (MDM) was performed according to clinically-selected variables. Regression discontinuity analyses were performed as an additional line of sensitivity analysis to estimate local treatment effects at the 10-cm tumor size cutoff.

Results

Of 2,890 patients with tumours ≥3 cm, there were 205 huge tumors. After 1:1 CEM, 174 huge tumors were matched to 174 large tumors; and after 1:2 MDM, 190 huge tumours were matched to 380 large tumours. There was significantly and consistently increased intraoperative blood loss, frequency in the application of Pringle maneuver, major morbidity and postoperative stay in the huge tumour group compared to the large tumour group after both 1:1 CEM and 1:2 MDM. These findings were reinforced in RD analyses. Intraoperative blood transfusion rate and open conversion rate were significantly higher in the huge tumor group after only 1:2 MDM but not 1:1 CEM.

Conclusions

MILR for huge tumours can be safely performed in expert centers It is an operation with substantial complexity and high technical requirement, with worse perioperative outcomes compared to MILR for large tumors, therefore judicious patient selection is pivotal.

Comparison between short and long-term outcomes after minimally invasive versus open primary liver resections for hepatocellular carcinoma: A 1:1 matched analysis

BACKGROUND

This study aims to compare the short- and long-term outcomes of patients undergoing minimally invasive liver resection (MILR) versus open liver resection (OLR) for nonrecurrent hepatocellular carcinoma (HCC).

METHODS

Review of 204 MILR and 755 OLR without previous LR performed between 2005 and 2018. 1:1 coarsened exact matching (CEM) and 1:1 propensity-score matching (PSM) were performed.

RESULTS

Overall, 190 MILR were well-matched with 190 OLR by PSM and 86 MILR with 86 OLR by CEM according to patient baseline characteristics. After PSM and CEM, MILR was associated with a significantly longer operation time [230 min (interquartile range [IQR], 145-330) vs. 160 min (IQR, 125-210), p < .001] [215 min (IQR, 135-295) vs. 153.5 min (120-180), p < .001], shorter postoperative stay [4 days (IQR, 3-6) vs. 6 days (IQR, 5-8), p = .001)] [4 days (IQR, 3-5) vs. 6 days (IQR, 5-7), p = .004] and lower postoperative morbidity [40 (21%) vs. 67 (35.5%), p = .003] [16 (18.6%) vs. 27 (31.4%), p = .036] compared to OLR. MILR was also associated with a significantly longer median time to recurrence (70 vs. 40.3 months, p = .014) compared to OLR after PSM but not CEM. There was no significant difference in terms of overall survival and recurrence-free survival.

CONCLUSION

MILR is associated with superior short-term postoperative outcomes and with at least equivalent long-term oncological outcomes compared to OLR for HCC.

Robotic liver surgery: literature review and future perspectives

INTRODUCTION

Minimally invasive liver resections (MILR) have been gaining popularity over the last decades. MILR provides superior peri-operative outcome. Despite these advantages, the penetrance of MILR in the clinical setting has been limited, and it was slowed down, among other factors, also by the laparoscopic technological limitations.

EVIDENCE ACQUISITION

A literature review has been carried out (Pubmed, Embase and Scopus platforms) focusing on the role of robotic surgery in MILR.

EVIDENCE SYNTHESIS

The literature review results are presented and our additional remarks on the topic are discussed.

CONCLUSIONS

Robotic MILR has been helping to expand the penetrance of MIS in liver surgery by making possible increasingly more challenging procedures. Minor resections still represent most of the robotic liver surgery data currently available. Robotic liver surgery is safe and effective, and it shows perioperative outcomes comparable with laparoscopic and open surgery. The oncological efficacy, within the limitations of the current level of evidence (mostly retrospective studies and literature heterogeneity), seems to show promising result. High quality prospective randomized studies, the use of prospective registry data, and multi-institutional efforts are needed.

Minimally invasive versus open right anterior sectionectomy and central hepatectomy for central liver malignancies: a propensity-score-matched analysis

BACKGROUND

The utility of minimally-invasive liver resection (MILR) for deep centrally located tumours (CLT) remains controversial. We aimed to review our institution's experience and outcomes with minimally invasive central hepatectomy (CH) and right anterior sectionectomy (RAS) for CLT in a propensity score-matched (PSM) analysis.

METHODS

Retrospective review of a prospectively maintained surgical database revealed 23 patients who underwent MILR (6 CH, 17 RAS) and 53 patients who underwent open liver resection (OLR; 24 CH, 29 RAS) for CLT. PSM in a 1:1 ratio identified two groups of patients with similar baseline clinicopathological characteristics. Peri-operative outcomes were then compared.

RESULTS

There was one laparoscopic-assisted, one robot-assisted and two laparoscopic-converted-open procedures in the MILR cohort. Across the unmatched cohort, there was only one mortality (MILR) and five patients with major morbidity (all OLR). MILR was associated with a longer operating time (P < 0.001), but shorter post-operative hospital stay (P = 0.002) and decreased morbidity (P = 0.018) in the unmatched cohort. Examination of peri-operative outcomes after PSM revealed that MILR was similarly associated with a longer operating time (P = 0.001) and shortened post-operative hospital stay (P = 0.043). OLR was associated with a significantly reduced application of Pringle manoeuvre (P = 0.004). There were no significant differences between MILR and OLR with regards to blood loss, blood transfusions, morbidity and margin status in the PSM analysis.

CONCLUSION

MILR for CLT is safe and feasible when performed by experienced surgeons. It is associated with shorter hospital stays but at the expense of longer operation times and more frequent application of Pringle manoeuver.

Robotic ICG guided anatomical liver resection in a multi-centre cohort: an evolution from "positive staining" into "negative staining" method

BACKGROUND

Laparoscopic major anatomical liver resection is challenging. The robotic liver resection (RLR) approach, with Firefly indocyanine green (ICG) imaging, was proposed to overcome the limitations of laparoscopy. The aim of this multi-centre international study was to evaluate the use of Firefly ICG imaging in anatomical RLR.

METHODS

A retrospective study of consecutive patients undergoing RLR anatomical resection with intra-operative ICG administration from January 2015 to July 2018 were enrolled. Patients who underwent simultaneous or en-bloc resections of other organs were excluded.

RESULTS

A total of 52 patients were recruited of which 32 patients were healthy donors, 17 with malignancy and 3 for benign conditions. 12 patients had cirrhosis. 28 patients underwent a right hepatectomy (53.8%) with left hepatectomy performed with 18 patients. 40 patients underwent negative staining and 12 patients via direct portal vein injection for positive staining. ICG demarcation line was visualized in 43 patients and was clearer than the ischaemic demarcation line in 29 patients. All resections for malignancy had clear margins. There were no 30-day/inpatient mortalities.

CONCLUSION

Robotic ICG guided hepatectomy technique for anatomical liver resection is safe, feasible and has the benefit for improved visualization in healthy donors and cirrhotic patients.

Outcome of minimally invasive liver resection for extrapancreatic biliary malignancies: A single-institutional experience

Background:

Minimally invasive liver resection (MILR) has been increasingly adopted over the past decade, and its application has been expanded to the management of extrapancreatic biliary malignancies (EPBMs). We aimed to evaluate the peri- and post-operative outcome of patients undergoing MILR for suspected EPMB.

Methods:

Forty-four consecutive patients who underwent MILR with a curative intent for EPBM at Singapore General Hospital between 2011 and 2018 were identified from a prospectively maintained surgical database. Clinical and operative data were analysed and compared to provide information and make comparisons on peri- and post-operative outcomes.

Results:

A total of 26, 5 and 13 patients underwent MILR for intrahepatic cholangiocarcinoma (ICC), perihilar cholangiocarcinoma (PHC) and gallbladder carcinoma (GBCA), respectively. Six major hepatectomies were performed, of which one was laparoscopic assisted and another was robot assisted. Ten patients underwent posterosuperior segmentectomies. There was one open conversion. The mean operative time was 266.5 min, and the mean blood loss was 379 ml. The mean length of hospital stay was 4.7 days with no incidences of 30- and 90-day mortality. The rate of recurrence-free survival (RFS) was 75% (at least 12-month follow-up). There was a significantly higher rate of robot-assisted procedures in patients undergoing MILR for GBCA/PHC as compared to ICC (P = 0.034). Patients undergoing posterosuperior segmentectomies required longer operative time (P = 0.018) with an increased need for (P = 0.001) and duration of (P = 0.025) Pringles manoeuvre. There were no differences in operative time, blood loss, morbidity, mortality or RFS between the above groups.

Conclusion:

Minimally invasive surgery can be adopted safely with a low open conversion rate for EPBMs.

Adoption of Robotic Liver, Pancreatic and Biliary Surgery in Singapore: A Single Institution Experience with Its First 100 Consecutive Cases

Introduction: Presently, robotic hepatopancreatobiliary surgery (RHPBS) is increasingly adopted worldwide. This study reports our experience with the first 100 consecutive cases of RHPBS in Singapore. Methods: Retrospective review of a single-institution prospective database of the first 100 consecutive RHPBS performed over 6 years from February 2013 to February 2019. Eighty-six cases were performed by a single surgeon. Results: The 100 consecutive cases included 24 isolated liver resections, 48 pancreatic surgeries (including 2 bile duct resections) and 28 biliary surgeries (including 8 with concomitant liver resections). They included 10 major hepatectomies, 15 pancreaticoduodenectomies, 6 radical resections for gallbladder carcinoma and 8 hepaticojejunostomies. The median operation time was 383 minutes, with interquartile range (IQR) of 258 minutes and there were 2 open conversions. The median blood loss was 200ml (IQR 350ml) and 15 patients required intra-operative blood transfusion. There were no post-operative 90-day nor in-hospital mortalities but 5 patients experienced major (> grade 3a) morbidities. The median post-operative stay was 6 days (IQR 5 days) and there were 12 post-operative 30-day readmissions. Comparison between the first 50 and the subsequent 50 patients demonstrated a significant reduction in blood loss, significantly lower proportion of malignant indications, and a decreasing frequency in liver resections performed. Conclusion: Our experience with the first 100 consecutive cases of RHPBS confirms its feasibility and safety when performed by experienced laparoscopic hepatopancreatobiliary surgeons. It can be performed for even highly complicated major hepatopancreatobiliary surgery with a low open conversion rate. Keywords: Biliary surgery, hepaticojejunostomy, liver resection, pancreas, pancreaticoduodenectomy

The impact of robotics in liver surgery: A worldwide systematic review and short-term outcomes meta-analysis on 2,728 cases

BACKGROUND

The dissemination of robotic liver surgery is slow-paced and must face the obstacle of demonstrating advantages over open and laparoscopic (LLS) approaches. Our objective was to show the current position of robotic liver surgery (RLS) worldwide and to identify if improved short-term outcomes are observed, including secondary meta-analyses for type of resection, etiology, and cost analysis.

METHODS

A PRISMA-based systematic review was performed to identify manuscripts comparing RLS vs open or LLS approaches. Quality analysis was performed using the Newcatle-Ottawa score. Statistical analysis was performed after heterogeneity test and fixed- or random-effect models were chosen accordingly.

RESULTS

After removing duplications, 2728 RLS cases were identified from the final set of 150 manuscripts. More than 75% of the cases have been performed on malignancies. Meta-analysis from the 38 comparative reports showed that RLS may offer improved short-term outcomes compared to open procedures in most of the variables screened. Compared to LLS, some advantages may be observed in favour of RLS for major resections in terms of operative time, hospital stay and rate of complications. Cost analyses showed an increased cost per procedure of around US$5000.

CONCLUSIONS

The advantages of RLS still need to be demonstrated although early results are promising. Advantages vs open approach are demonstrated. Compared to laparoscopic surgery, minor perioperative advantages may be observed for major resections although cost analyses are still unfavorable to the robotic approach.

Applying the Delphi process for development of a hepatopancreaticobiliary robotic surgery training curriculum

BACKGROUND

Robotic hepatopancreaticobiliary (HPB) procedures are performed worldwide and establishing processes for safe adoption of this technology is essential for patient benefit. We report results of the Delphi process to define and optimize robotic training procedures for HPB surgeons.

METHODS

In 2019, a robotic HPB surgery panel with an interest in surgical training from the Americas and Europe was created and met. An e-consensus-finding exercise using the Delphi process was applied and consensus was defined as 80% agreement on each question. Iterations of anonymous voting continued over three rounds.

RESULTS

Members agreed on several points: there was need for a standardized robotic training curriculum for HPB surgery that considers experience of surgeons and based on a robotic hepatectomy includes a common approach for "basic robotic skills" training (e-learning module, including hardware description, patient selection, port placement, docking, troubleshooting, fundamentals of robotic surgery, team training and efficiency, and emergencies) and an "advanced technical skills curriculum" (e-learning, including patient selection information, cognitive skills, and recommended operative equipment lists). A modular approach to index procedures should be used with video demonstrations, port placement for index procedure, troubleshooting, and emergency scenario management information. Inexperienced surgeons should undergo training in basic robotic skills and console proficiency, transitioning to full procedure training of e-learning (video demonstration, simulation training, case observation, and final evaluation). Experienced surgeons should undergo basic training when using a new system (e-learning, dry lab, and operating room (OR) team training, virtual reality modules, and wet lab; case observations were unnecessary for basic training) and should complete the advanced index procedural robotic curriculum with assessment by wet lab, case observation, and OR team training.

CONCLUSIONS

Optimization and standardization of training and education of HPB surgeons in robotic procedures was agreed upon. Results are being incorporated into future curriculum for education in robotic surgery.

Robotic Liver Resection

Robotic surgery has rapidly evolved. It is particularly attractive as an alternative minimally invasive approach in liver surgery because of improvements in visualization and articulated instruments. Limitations include increased operative times and lack of tactile feedback, but these have not been shown in studies. Considerations unique to robotic surgery, including safety protocols, must be put in place and be reviewed at the beginning of every procedure to ensure safety in the event of an emergent conversion. Despite the lack of early adoption by many hepatobiliary surgeons, robotic liver surgery continues to evolve and find its place within hepatobiliary surgery.

Novel method of intraoperative liver tumour localisation with indocyanine green and near-infrared imaging

INTRODUCTION

Fluorescence imaging (FI) with indocyanine green (ICG) is increasingly implemented as an intraoperative navigation tool in hepatobiliary surgery to identify hepatic tumours. This is useful in minimally invasive hepatectomy, where gross inspection and palpation are limited. This study aimed to evaluate the feasibility, safety and optimal timing of using ICG for tumour localisation in patients undergoing hepatic resection.

METHODS

From 2015 to 2018, a prospective multicentre study was conducted to evaluate feasibility and safety of ICG in tumour localisation following preoperative administration of ICG either on Day 0-3 or Day 4-7.

RESULTS

Among 32 patients, a total of 46 lesions were resected: 23 were hepatocellular carcinomas (HCCs), 12 were colorectal liver metastases (CRLM) and 11 were benign lesions. ICG FI identified 38 (82.6%) lesions prior to resection. The majority of HCCs were homogeneous fluorescing lesions (56.6%), while CLRM were homogeneous (41.7%) or rim-enhancing (33.3%). The majority (75.0%) of the lesions not detected by ICG FI were in cirrhotic livers. Most (84.1%) of ICG-positive lesions detected were < 1 cm deep, and half of the lesions ≥ 1 cm in depth were not detected. In cirrhotic patients with malignant lesions, those given ICG on preoperative Day 0-3 and Day 4-7 had detection rates of 66.7% and 91.7%, respectively. There were no adverse events.

CONCLUSION

ICG FI is a safe and feasible method to assist tumour localisation in liver surgery. Different tumours appear to display characteristic fluorescent patterns. There may be no disadvantage of administering ICG closer to the operative date if it is more convenient, except in patients with liver cirrhosis.

International consensus statement on robotic hepatectomy surgery in 2018

The robotic surgical system has been applied in liver surgery. However, controversies concerns exist regarding a variety of factors including the safety, feasibility, efficacy, and cost-effectiveness of robotic surgery. To promote the development of robotic hepatectomy, this study aimed to evaluate the current status of robotic hepatectomy and provide sixty experts’ consensus and recommendations to promote its development. Based on the World Health Organization Handbook for Guideline Development, a Consensus Steering Group and a Consensus Development Group were established to determine the topics, prepare evidence-based documents, and generate recommendations. The GRADE Grid method and Delphi vote were used to formulate the recommendations. A total of 22 topics were prepared analyzed and widely discussed during the 4 meetings. Based on the published articles and expert panel opinion, 7 recommendations were generated by the GRADE method using an evidence-based method, which focused on the safety, feasibility, indication, techniques and cost-effectiveness of hepatectomy. Given that the current evidences were low to very low as evaluated by the GRADE method, further randomized-controlled trials are needed in the future to validate these recommendations.

Changing trends and outcomes associated with the adoption of minimally invasive hepatectomy: a contemporary single-institution experience with 400 consecutive resections

BACKGROUND

Several studies published mainly from pioneers and early adopters have documented the evolution of minimally invasive hepatectomy (MIH). However, questions remain if these reported experiences are applicable and reproducible today. This study examines the changing trends, safety, and outcomes associated with the adoption of MIH based on a contemporary single-institution experience.

METHODS

This is a retrospective review of 400 consecutive patients who underwent MIH between 2006 and 2017 of which 360 cases (90%) were performed since 2012. To determine the evolution of MIH, the study population was stratified into four equal groups of 100 patients. Analyses were also performed of predictive factors and outcomes of open conversion.

RESULTS

Four hundred patients underwent MIH of which 379 (94.8%) were totally laparoscopic/robotic. Eighty-eight (22.0%) patients underwent major hepatectomy and 160 (40.0%) had resection of tumors located in the posterosuperior segments. There were 38 (9.5%) open conversions. Comparison across the four groups demonstrated that patients were older, had higher ASA score, and had increased frequency of previous abdominal surgery and repeat liver resections. There was also an increase in the proportion of patients who underwent totally laparoscopic/robotic surgery, major liver resection, resection of ≥ 3 segments, and multiple resections. Comparison of outcomes demonstrated that there was a significant decrease in open conversion rate, longer operation time, and increased use of Pringles maneuver. The presence of cirrhosis and institution experience (1st 100 cases) were independent predictors of open conversion. Patients who required open conversion had significantly increased operation time, blood loss, blood transfusion rate, morbidity, and mortality.

CONCLUSION

The case volume of MIH performed increased rapidly at our institution over time. Although the indications of MIH expanded to include higher risk patients and more complex hepatectomies, there was a decrease in open conversion rate and no change in other perioperative outcomes.