Impact of liver cirrhosis on the difficulty of minimally-invasive liver resections: a 1:1 coarsened exact-matched controlled study

Navigating Complexity in Liver Resection: A Narrative Review of Factors Influencing Intraoperative Difficulty

Background: Liver resection remains the cornerstone for curative management in primary liver malignancies. Liver surgery ranges from simple wedge resections to complex hepatectomies involving vascular or biliary reconstructions. The anatomical complexity of the liver and these varied surgical approaches create challenges in assessing operative difficulty. This literature review explores the key factors influencing operative difficulty in liver resection for primary liver malignancy across surgical techniques. Methods: A broad literature review was conducted to determine the factors that were associated with increased operative difficulty in liver resection using the Embase, PubMed, and Cochrane databases for studies published between 2000 and 2025. Results: This review identifies several patient, tumor, and surgical factors that influence operative difficulty in liver resection. Numerous difficult scoring systems were identified, yet their applicability across different operative approaches remains uncertain. Across open and minimally invasive techniques, tumor size and location are commonly used to determine complexity. However, debate remains regarding the optimal cutoff for tumor diameter. Other identified factors include the extent of resection, patient-specific variables (e.g., cirrhosis, body mass index, previous surgeries), and surgical technique. In addition, liver resection procedures classified based on the 2000 Brisbane terminology have been stratified into three groups of increasing difficulty. Conclusion: The ability to predict operative difficulty is useful for case selection, surgical planning, and risk stratification for meaningful shared decision-making. Future research should focus on refining predictive models by integrating composite measures, including patient-reported outcomes and long-term survival. A unified, validated scoring system applicable across surgical techniques could enhance consistency in clinical practice and research to improve outcomes.

Perioperative impact of liver cirrhosis on robotic liver resection for hepatocellular carcinoma: a retrospective cohort study

BACKGROUND

The safety and efficacy of robotic liver resection (RLR) for patients with hepatocellular carcinoma (HCC) have been reported worldwide. However, the exact role of RLR in HCC patients with liver cirrhosis is not sufficiently determined.

METHODS

We conducted a retrospective study on consecutive patients with cirrhosis or non-cirrhosis who received RLR for HCC from 2018 to 2023. Data on patients' demographics and perioperative outcomes were collected and analyzed. Propensity score matching (PSM) analysis was performed. Multivariate logistic regression analysis was performed to determine the risk factors of prolonged postoperative length of stay (LOS) and morbidity.

RESULTS

Of the 571 patients included, 364 (64%) had cirrhosis. Among the cirrhotic patients, 48 (13%) were classified as Child-Pugh B. After PSM, the cirrhosis and non-cirrhosis group (n = 183) had similar operative time, estimated blood loss, postoperative blood transfusion, LOS, overall morbidity (p > 0.05). In addition, the intraoperative and postoperative outcomes were similar between the two groups in the subgroup analyses of patients with tumor size ≥ 5 cm, major hepatectomy, and high/expert IWATE difficulty grade. However, patients with Child-Pugh B cirrhosis had longer LOS and more overall morbidity than that of Child-Pugh A. Child-Pugh B cirrhosis, ASA score > 2, longer operative time, and multiple tumors were risk factors of prolonged LOS or morbidity in patients with cirrhosis.

CONCLUSION

The presence of Child-Pugh A cirrhosis didn't significantly influence the difficulty and perioperative outcomes of RLR for selected patients with HCC. However, even in high-volume center, Child-Pugh B cirrhosis was a risk factor for poor postoperative outcomes.

Factors Associated with and Impact of Open Conversion in Laparoscopic and Robotic Minor Liver Resections: An International Multicenter Study of 10,541 Patients

INTRODUCTION

Despite the increasing widespread adoption and experience in minimally invasive liver resections (MILR), open conversion occurs not uncommonly even with minor resections and as been reported to be associated with inferior outcomes. We aimed to identify risk factors for and outcomes of open conversion in patients undergoing minor hepatectomies. We also studied the impact of approach (laparoscopic or robotic) on outcomes.

METHODS

This is a post-hoc analysis of 20,019 patients who underwent RLR and LLR across 50 international centers between 2004-2020. Risk factors for and perioperative outcomes of open conversion were analysed. Multivariate and propensity score-matched analysis were performed to control for confounding factors.

RESULTS

Finally, 10,541 patients undergoing either laparoscopic (LLR; 89.1%) or robotic (RLR; 10.9%) minor liver resections (wedge resections, segmentectomies) were included. Multivariate analysis identified LLR, earlier period of MILR, malignant pathology, cirrhosis, portal hypertension, previous abdominal surgery, larger tumor size, and posterosuperior location as significant independent predictors of open conversion. The most common reason for conversion was technical issues (44.7%), followed by bleeding (27.2%), and oncological reasons (22.3%). After propensity score matching (PSM) of baseline characteristics, patients requiring open conversion had poorer outcomes compared with successful MILR cases as evidenced by longer operative times, more blood loss, higher requirement for perioperative transfusion, longer duration of hospitalization and higher morbidity, reoperation, and 90-day mortality rates.

CONCLUSIONS

Multiple risk factors were associated with conversion of MILR even for minor hepatectomies, and open conversion was associated with significantly poorer perioperative outcomes.

Effect of Preoperative Malnutrition Based on Albumin and BMI on Hepatocellular Carcinoma Surgery and Prediction of Risk Factors of Complications

BACKGROUND

To investigate the correlation between preoperative malnutrition and perioperative variables in patients with hepatocellular carcinoma (HCC) and to analyze the risk factors of complications after HCC resection.

METHODS

All patients who underwent hepatectomy because of HCC in the First Affiliated Hospital of Chongqing Medical University from June 1, 2018, to December 1, 2021, were analyzed retrospectively. Preoperative malnutrition was defined as body mass index (BMI) < 18.5 kg/m2 or serum albumin level < 3.5 g/dL within 30 days before operation.

RESULTS

A total of 415 patients with HCC hepatectomy were included, and 75 (18.1%) were classified as malnutrition group. In the malnutrition group, blood loss (662.1 ± 748.1 VS 404.6 ± 681.9, P = 0.002), transfusion rate (36.0% VS 13.5%, P < 0.001), postoperative hospital stays (13.3 ± 9.6 VS 10.1 ± 4.2, P < 0.001), 30-day postoperative mortality (4.0 VS 0.6%, P = 0.043), complications rate (68% VS 34.8%, P < 0.001), and severe complication rate (17.3% VS 2.4%, P < 0.001) were significantly higher than those in the well-nourished group. Multivariate analysis showed that age (HR 1.037, 95% CI 1.015-1.059, P = 0.001), preoperative malnutrition (HR 2.933, 95% CI 1.515-5.679, P = 0.001), simultaneous cholecystectomy (HR 2.004, 95% CI 1.168-3.440, P = 0.012), cirrhosis (HR 4.997, 95% CI 2.864-8.718, P < 0.001), and transfusion (HR 5.166, 95% CI 2.272-11.748, P < 0.001) were independent risk factors for postoperative complications. In addition, preoperative malnutrition (HR 8.209, 95% CI 2.711-24.864, P < 0.001) and operation time (HR 1.088, 95% CI 1.003-1.103, P = 0.004) were independent risk factors for severe complications.

CONCLUSION

Preoperative malnutrition can adversely affect the outcome of HCC resection. For patients with advanced age, cirrhosis, and malnutrition, preoperative planning is very important, and we should be more careful during the operation to avoid transfusion caused by bleeding and not to carry out preventive cholecystectomy, which are helpful to reduce the occurrence of postoperative complications.

Early experience with pure laparoscopic donor hepatectomy: comparison with open donor hepatectomy and non-donor laparoscopic hepatectomy

BACKGROUND

Pure laparoscopic donor hepatectomy (L-DH) has seen a rise in uptake in recent years following the popularization of minimally invasive modality for major hepatobiliary surgery. Our study aimed to determine the safety and compare the perioperative outcomes of L-DH with open donor hepatectomy (O-DH) and laparoscopic non donor hepatectomy (L-NDH) based on our single institution experience.

METHODS

Eighty of 113 laparoscopic hemi-hepatectomies performed between 2015 and 2022 met study inclusion criteria. Of these, 11 were L-DH. PSM in a 1:2 ratio of L-DH versus L-NDH and 1:1 ratio of L-DH versus O-DH were performed, identifying patients with similar baseline clinicopathological characteristics.

RESULTS

After 2:1 matching, the L-DH cohort were significantly younger (P < 0.001) and had lower ASA scores (P < 0.001) than the L-NDH cohort. L-DH was associated with a longer median operating time (P < 0.001) and shorter median postoperative stay (P < 0.001) than L-NDH. After 1:1 matching, there were no significant differences in baseline demographic between the L-DH and O-DH cohorts. L-DH was associated with lower median blood loss (P = 0.040) and shorter length of stay compared to O-DH (P = 0.004). There were no significant differences in recipient outcomes for both cohorts.

CONCLUSION

L-DH can be adopted safely by surgeons experienced in L-NDH and ODH. It is associated with decreased blood loss and shorter length of stay compared to O-DH.

Propensity Score-Matching Analysis Comparing Robotic Versus Laparoscopic Limited Liver Resections of the Posterosuperior Segments: An International Multicenter Study

OBJECTIVE

The purpose of this study was to compare the outcomes of robotic limited liver resections (RLLR) versus laparoscopic limited liver resections (LLLR) of the posterosuperior segments.

BACKGROUND

Both laparoscopic and robotic liver resections have been used for tumors in the posterosuperior liver segments. However, the comparative performance and safety of both approaches have not been well examined in the existing literature.

METHODS

This is a post hoc analysis of a multicenter database of 5446 patients who underwent RLLR or LLLR of the posterosuperior segments (I, IVa, VII, and VIII) at 60 international centers between 2008 and 2021. Data on baseline demographics, center experience and volume, tumor features, and perioperative characteristics were collected and analyzed. Propensity score-matching (PSM) analysis (in both 1:1 and 1:2 ratios) was performed to minimize selection bias.

RESULTS

A total of 3510 cases met the study criteria, of whom 3049 underwent LLLR (87%), and 461 underwent RLLR (13%). After PSM (1:1: and 1:2), RLLR was associated with a lower open conversion rate [10 of 449 (2.2%) vs 54 of 898 (6.0%); P =0.002], less blood loss [100 mL [IQR: 50-200) days vs 150 mL (IQR: 50-350); P <0.001] and a shorter operative time (188 min (IQR: 140-270) vs 222 min (IQR: 158-300); P <0.001]. These improved perioperative outcomes associated with RLLR were similarly seen in a subset analysis of patients with cirrhosis-lower open conversion rate [1 of 136 (0.7%) vs 17 of 272 (6.2%); P =0.009], less blood loss [100 mL (IQR: 48-200) vs 160 mL (IQR: 50-400); P <0.001], and shorter operative time [190 min (IQR: 141-258) vs 230 min (IQR: 160-312); P =0.003]. Postoperative outcomes in terms of readmission, morbidity and mortality were similar between RLLR and LLLR in both the overall PSM cohort and cirrhosis patient subset.

CONCLUSIONS

RLLR for the posterosuperior segments was associated with superior perioperative outcomes in terms of decreased operative time, blood loss, and open conversion rate when compared with LLLR.

Impact of Liver Cirrhosis, Severity of Cirrhosis, and Portal Hypertension on the Difficulty and Outcomes of Laparoscopic and Robotic Major Liver Resections for Primary Liver Malignancies

BACKGROUND

Minimally invasive liver resections (MILR) offer potential benefits such as reduced blood loss and morbidity compared with open liver resections. Several studies have suggested that the impact of cirrhosis differs according to the extent and complexity of resection. Our aim was to investigate the impact of cirrhosis on the difficulty and outcomes of MILR, focusing on major hepatectomies.

METHODS

A total of 2534 patients undergoing minimally invasive major hepatectomies (MIMH) for primary malignancies across 58 centers worldwide were retrospectively reviewed. Propensity score (PSM) and coarsened exact matching (CEM) were used to compare patients with and without cirrhosis.

RESULTS

A total of 1353 patients (53%) had no cirrhosis, 1065 (42%) had Child-Pugh A and 116 (4%) had Child-Pugh B cirrhosis. Matched comparison between non-cirrhotics vs Child-Pugh A cirrhosis demonstrated comparable blood loss. However, after PSM, postoperative morbidity and length of hospitalization was significantly greater in Child-Pugh A cirrhosis, but these were not statistically significant with CEM. Comparison between Child-Pugh A and Child-Pugh B cirrhosis demonstrated the latter had significantly higher transfusion rates and longer hospitalization after PSM, but not after CEM. Comparison of patients with cirrhosis of all grades with and without portal hypertension demonstrated no significant difference in all major perioperative outcomes after PSM and CEM.

CONCLUSIONS

The presence and severity of cirrhosis affected the difficulty and impacted the outcomes of MIMH, resulting in higher blood transfusion rates, increased postoperative morbidity, and longer hospitalization in patients with more advanced cirrhosis. As such, future difficulty scoring systems for MIMH should incorporate liver cirrhosis and its severity as variables.

Impact of liver cirrhosis, severity of cirrhosis and portal hypertension on the difficulty of laparoscopic and robotic minor liver resections for primary liver malignancies in the anterolateral segments

INTRODUCTION

We performed this study in order to investigate the impact of liver cirrhosis (LC) on the difficulty of minimally invasive liver resection (MILR), focusing on minor resections in anterolateral (AL) segments for primary liver malignancies.

METHODS

This was an international multicenter retrospective study of 3675 patients who underwent MILR across 60 centers from 2004 to 2021.

RESULTS

1312 (35.7%) patients had no cirrhosis, 2118 (57.9%) had Child A cirrhosis and 245 (6.7%) had Child B cirrhosis. After propensity score matching (PSM), patients in Child A cirrhosis group had higher rates of open conversion (p = 0.024), blood loss >500 mls (p = 0.001), blood transfusion (p < 0.001), postoperative morbidity (p = 0.004), and in-hospital mortality (p = 0.041). After coarsened exact matching (CEM), Child A cirrhotic patients had higher open conversion rate (p = 0.05), greater median blood loss (p = 0.014) and increased postoperative morbidity (p = 0.001). Compared to Child A cirrhosis, Child B cirrhosis group had longer postoperative stay (p = 0.001) and greater major morbidity (p = 0.012) after PSM, and higher blood transfusion rates (p = 0.002), longer postoperative stay (p < 0.001), and greater major morbidity (p = 0.006) after CEM. After PSM, patients with portal hypertension experienced higher rates of blood loss >500 mls (p = 0.003) and intraoperative blood transfusion (p = 0.025).

CONCLUSION

The presence and severity of LC affect and compound the difficulty of MILR for minor resections in the AL segments. These factors should be considered for inclusion into future difficulty scoring systems for MILR.

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.

Comparing Outcomes of Minimally Invasive and Open Hepatectomy for Primary Liver Malignancies in Patients with Low-MELD Cirrhosis

INTRODUCTION

Cirrhotic patients with primary liver cancer may undergo curative-intent resection when selected appropriately. Patients with T1 tumors and low-MELD are generally referred for resection. We aim to evaluate whether minimally invasive hepatectomy (MIH) is associated with improved outcomes versus open hepatectomy (OH).

METHODS

NSQIP hepatectomy database 2014-2021 was used to select patients with T1 Hepatocellular Carcinoma (HCC) or Intra-hepatic Cholangiocarcionoma (IHCC) and low-MELD cirrhosis (MELD ≤ 10) who underwent partial hepatectomy. Propensity score matching was applied between OH and MIH patients, and 30-day postoperative outcomes were compared. Multivariable regression was used to identify predictors of post-hepatectomy liver failure (PHLF) in the selected population.

RESULTS

There were 922 patients: 494 (53.6%) OH, 372 (40.3%) MIH, and 56 (6.1%) began MIH converted to OH (analyzed with the OH cohort). We matched 354 pairs of patients with an adequate balance between the groups. MIH was associated with lower rates of bile leak (HR 0.37 [0.19-0.72)], PHLF (HR 0.36 [0.15-0.86]), collections requiring drainage (HR 0.30 [0.15-0.63]), postoperative transfusion (HR 0.36 [0.21-0.61]), major (HR 0.45 [0.27-0.77]), and overall morbidity (HR 0.44 [0.31-0.63]), and a two-day shorter median hospitalization (3 vs. 5 days; HR 0.61 [0.45-0.82]). No difference was noted in operative time, wound, respiratory, and septic complications, or mortality. Regression analysis identified ascites, prior portal vein embolization (PVE), additional hepatectomies, Pringle's maneuver, and OH (vs. MIH) as independent predictors of PHLF.

CONCLUSION

MIH for early-stage HCC/IHCC in low-MELD cirrhotic patients was associated with improved postoperative outcomes over OH. These findings suggest that MIH should be considered an acceptable approach in this population of patients.

Open Versus Laparoscopic Right Hepatectomy for Hepatocellular Carcinoma Following Sequential TACE-PVE: A Multicentric Comparative Study

BACKGROUND

Right hepatectomy (RH) for hepatocellular carcinoma (HCC) is ideally preceded by transcatheter arterial chemoembolization (TACE) and portal vein embolization (PVE). Laparoscopic approach improves short-term outcome and textbook outcome (TO), which reflects the "ideal" surgical outcome, after RH. However, laparoscopic RH on an underlying diseased liver and after TACE/PVE remains a challenging procedure. The aim of this study was to compare the outcomes in patients who underwent laparoscopic liver resection (LLR) or open liver resection (OLR) following TACE/PVE.

PATIENTS AND METHODS

All patients with HCC who underwent RH after TACE/PVE in five French centers were retrospectively included. Outcomes were compared between the LLR group and the OLR group using propensity score matching (PSM). Quality of surgical care was defined by TO.

RESULTS

Between 2005 and 2019, 117 patients were included (41 in LLR group, 76 in OLR group). Overall morbidity was comparable (51% versus 53%, p = 0.24). In LLR group, TO was completed in 66% versus 37% in OLR group (p = 0.02). LLR and absence of clamping were the only factors associated with TO completion [hazard ratio (HR) 4.27, [1.77-10.28], p = 0.001]. After PSM, 5-year overall survival (OS) and progression-free survival (PFS) were 55% in matched LLR versus 77% in matched OLR, p = 0.35, and 13% in matched LLR versus 17% in matched OLR, p = 0.97. TO completion was independently associated with a better 5-year OS (65.2% versus 42.5%, p = 0.007).

CONCLUSION

Major LLR after TACE/PVE should be considered as a valuable option in expert centers to increase the chance of TO, the latter being associated with a better 5-year OS.

Impact of liver cirrhosis and portal hypertension on minimally invasive limited liver resection for primary liver malignancies in the posterosuperior segments: An international multicenter study

INTRODUCTION

To assess the impact of cirrhosis and portal hypertension (PHT) on technical difficulty and outcomes of minimally invasive liver resection (MILR) in the posterosuperior segments.

METHODS

This is a post-hoc analysis of patients with primary malignancy who underwent laparoscopic and robotic wedge resection and segmentectomy in the posterosuperior segments between 2004 and 2019 in 60 centers. Surrogates of difficulty (i.e, open conversion rate, operation time, blood loss, blood transfusion, and use of the Pringle maneuver) and outcomes were compared before and after propensity-score matching (PSM) and coarsened exact matching (CEM).

RESULTS

Of the 1954 patients studied, 1290 (66%) had cirrhosis. Among the cirrhotic patients, 310 (24%) had PHT. After PSM, patients with cirrhosis had higher intraoperative blood transfusion (14% vs. 9.3%; p = 0.027) and overall morbidity rates (20% vs. 14.5%; p = 0.023) than those without cirrhosis. After coarsened exact matching (CEM), patients with cirrhosis tended to have higher intraoperative blood transfusion rate (12.1% vs. 6.7%; p = 0.059) and have higher overall morbidity rate (22.8% vs. 12.5%; p = 0.007) than those without cirrhosis. After PSM, Pringle maneuver was more frequently applied in cirrhotic patients with PHT (62.2% vs. 52.4%; p = 0.045) than those without PHT.

CONCLUSION

MILR in the posterosuperior segments in cirrhotic patients is associated with higher intraoperative blood transfusion and postoperative morbidity. This parameter should be utilized in the difficulty assessment of MILR.

Impact of liver cirrhosis, the severity of cirrhosis, and portal hypertension on the outcomes of minimally invasive left lateral sectionectomies for primary liver malignancies

BACKGROUND

The impact of cirrhosis and portal hypertension on perioperative outcomes of minimally invasive left lateral sectionectomies remains unclear. We aimed to compare the perioperative outcomes between patients with preserved and compromised liver function (noncirrhotics versus Child-Pugh A) when undergoing minimally invasive left lateral sectionectomies. In addition, we aimed to determine if the extent of cirrhosis (Child-Pugh A versus B) and the presence of portal hypertension had a significant impact on perioperative outcomes.

METHODS

This was an international multicenter retrospective analysis of 1,526 patients who underwent minimally invasive left lateral sectionectomies for primary liver malignancies at 60 centers worldwide between 2004 and 2021. In the study, 1,370 patients met the inclusion criteria and formed the final study group. Baseline clinicopathological characteristics and perioperative outcomes of these patients were compared. To minimize confounding factors, 1:1 propensity score matching and coarsened exact matching were performed.

RESULTS

The study group comprised 559, 753, and 58 patients who did not have cirrhosis, Child-Pugh A, and Child-Pugh B cirrhosis, respectively. Six-hundred and thirty patients with cirrhosis had portal hypertension, and 170 did not. After propensity score matching and coarsened exact matching, Child-Pugh A patients with cirrhosis undergoing minimally invasive left lateral sectionectomies had longer operative time, higher intraoperative blood loss, higher transfusion rate, and longer hospital stay than patients without cirrhosis. The extent of cirrhosis did not significantly impact perioperative outcomes except for a longer duration of hospital stay.

CONCLUSION

Liver cirrhosis adversely affected the intraoperative technical difficulty and perioperative outcomes of minimally invasive left lateral sectionectomies.

Risk Factors and Outcomes of Open Conversion During Minimally Invasive Major Hepatectomies: An International Multicenter Study on 3880 Procedures Comparing the Laparoscopic and Robotic Approaches

INTRODUCTION

Despite the advances in minimally invasive (MI) liver surgery, most major hepatectomies (MHs) continue to be performed by open surgery. This study aimed to evaluate the risk factors and outcomes of open conversion during MI MH, including the impact of the type of approach (laparoscopic vs. robotic) on the occurrence and outcomes of conversions.

METHODS

Data on 3880 MI conventional and technical (right anterior and posterior sectionectomies) MHs were retrospectively collected. Risk factors and perioperative outcomes of open conversion were analyzed. Multivariate analysis, propensity score matching, and inverse probability treatment weighting analysis were performed to control for confounding factors.

RESULTS

Overall, 3211 laparoscopic MHs (LMHs) and 669 robotic MHs (RMHs) were included, of which 399 (10.28%) had an open conversion. Multivariate analyses demonstrated that male sex, laparoscopic approach, cirrhosis, previous abdominal surgery, concomitant other surgery, American Society of Anesthesiologists (ASA) score 3/4, larger tumor size, conventional MH, and Institut Mutualiste Montsouris classification III procedures were associated with an increased risk of conversion. After matching, patients requiring open conversion had poorer outcomes compared with non-converted cases, as evidenced by the increased operation time, blood transfusion rate, blood loss, hospital stay, postoperative morbidity/major morbidity and 30/90-day mortality. Although RMH showed a decreased risk of conversion compared with LMH, converted RMH showed increased blood loss, blood transfusion rate, postoperative major morbidity and 30/90-day mortality compared with converted LMH.

CONCLUSIONS

Multiple risk factors are associated with conversion. Converted cases, especially those due to intraoperative bleeding, have unfavorable outcomes. Robotic assistance seemed to increase the feasibility of the MI approach, but converted robotic procedures showed inferior outcomes compared with converted laparoscopic procedures.

Impact of body mass index on the difficulty and outcomes of laparoscopic left lateral sectionectomy

INTRODUCTION

Currently, the impact of body mass index (BMI) on the outcomes of laparoscopic liver resections (LLR) is poorly defined. This study attempts to evaluate the impact of BMI on the peri-operative outcomes following laparoscopic left lateral sectionectomy (L-LLS).

METHODS

A retrospective analysis of 2183 patients who underwent pure L-LLS at 59 international centers between 2004 and 2021 was performed. Associations between BMI and selected peri-operative outcomes were analyzed using restricted cubic splines.

RESULTS

A BMI of >27kg/m2 was associated with increased in blood loss (Mean difference (MD) 21 mls, 95% CI 5-36), open conversions (Relative risk (RR) 1.13, 95% CI 1.03-1.25), operative time (MD 11 min, 95% CI 6-16), use of Pringles maneuver (RR 1.15, 95% CI 1.06-1.26) and reductions in length of stay (MD -0.2 days, 95% CI -0.3 to -0.1). The magnitude of these differences increased with each unit increase in BMI. However, there was a "U" shaped association between BMI and morbidity with the highest complication rates observed in underweight and obese patients.

CONCLUSION

Increasing BMI resulted in increasing difficulty of L-LLS. Consideration should be given to its incorporation in future difficulty scoring systems in laparoscopic liver resections.

Impact of neoadjuvant chemotherapy on the difficulty and outcomes of laparoscopic and robotic major liver resections for colorectal liver metastases: A propensity-score and coarsened exact-matched controlled study

BACKGROUND

Minimal invasive liver resections are a safe alternative to open surgery. Different scoring systems considering different risks factors have been developed to predict the risks associated with these procedures, especially challenging major liver resections (MLR). However, the impact of neoadjuvant chemotherapy (NAT) on the difficulty of minimally invasive MLRs remains poorly investigated.

METHODS

Patients who underwent laparoscopic and robotic MLRs for colorectal liver metastases (CRLM) performed across 57 centers between January 2005 to December 2021 were included in this analysis. Patients who did or did not receive NAT were matched based on 1:1 coarsened exact and 1:2 propensity-score matching. Pre- and post-matching comparisons were performed.

RESULTS

In total, the data of 5189 patients were reviewed. Of these, 1411 procedures were performed for CRLM, and 1061 cases met the inclusion criteria. After excluding 27 cases with missing data on NAT, 1034 patients (NAT: n = 641; non-NAT: n = 393) were included. Before matching, baseline characteristics were vastly different. Before matching, the morbidity rate was significantly higher in the NAT-group (33.2% vs. 27.2%, p-value = 0.043). No significant differences were seen in perioperative outcomes after the coarsened exact matching. After the propensity-score matching, statistically significant higher blood loss (mean, 300 (SD 128-596) vs. 250 (SD 100-400) ml, p-value = 0.047) but shorter hospital stay (mean, 6 [4-8] vs. 6 [5-9] days, p-value = 0.043) were found in the NAT-group.

CONCLUSION

The current study demonstrated that NAT had minimal impact on the difficulty and outcomes of minimally-invasive MLR for CRLM.

Predictors of recurrence following laparoscopic minor hepatectomy for hepatocellular carcinoma in the UK

AIMS

Minor hepatectomy, which is increasingly carried out laparoscopically (LLR), is a cornerstone of curative treatment for hepatocellular carcinoma (HCC). The majority of relevant publications however originate from regions with endemic viral hepatitis. Although the incidence of HCC in the UK is increasing, little is known about outcomes following LLR.

METHODS

Consecutive patients undergoing minor (involving ≤2 segments) LLR or open resection (OLR) at our institute between 2014 and 2021 were compared. Selection from a plethora of factors potentially impacting on overall (OS) and disease free survival (DFS) was optimised with Lasso regression. To enable analysis of patients having repeat resection, multivariate frailty modelling was utilised to calculate hazard ratios (HR).

RESULTS

The analysis of 111 liver resections included 55 LLR and 56 OLR. LLR was associated with a shorter hospital stay (5 ± 2 vs. 7 ± 2 days; p < 0.001) and a lower comprehensive complication index (4.43 vs. 9.96; p = 0.006). Mean OS (52.3 ± 2.3 vs. 49.9 ± 3.0 months) and DFS (33.9 ± 3.4 vs. 36.5 ± 3.6 months; p = 0.59) were comparable between LLR and OLR, respectively (median not reached). Presence of mixed cholangiocarcinoma/HCC, satellite lesions and AFP level predicted OS and DFS. In addition tumour size was predictive of DFS.

CONCLUSIONS

In the studied population minor LLR was associated with shorter hospital stay and fewer complications while offering non-inferior long-term outcomes. A number of predictors for disease free survival have been elucidated that may aid in identifying patients with a high risk of disease recurrence and need for further treatment.

Laparoscopic versus open resection of hepatocellular carcinoma in patients with cirrhosis

Hepatocellular carcinoma (HCC) is the sixth commonest malignancy worldwide, and the fourth-leading cause of cancer related death. Partial liver resection (LR) forms the mainstay of therapy for suitable patients with preserved liver function. In recent years, significant advances in surgical technology, refinement of operative techniques and improvements in peri-operative care have facilitated the widespread adoption of laparoscopic liver resection (LLR) with encouraging outcomes. Liver cirrhosis (LC) is present in up to 80% of patients with HCC, and adds a further dimension of complexity to LR. Cirrhotic patients have a propensity for greater intraoperative blood loss as well as increased postoperative complications such as refractory ascites and posthepatectomy liver failure. Tumor localization within the fibrotic parenchyma is challenging, giving rise to concerns about resection margin status. Patients are also at higher risk of developing metachronous lesions, which affects long-term survival. Presently, the exact role of LLR in HCC patients with underlying LC is not well-defined. Current evidence suggests that LLR offers a multitude of benefits in the short-term such as reduced blood loss and blood transfusion requirements and lower morbidity, when compared to open resection. Oncologic adequacy and long-term survival do not appear to be compromised. Special consideration must be given for LLR in patients with advanced cirrhosis, or those who require extensive major hepatectomies. We present here a brief review of the literature surrounding LLR for HCC on a background of LC.

The preoperative M2BPGi score predicts operative difficulty and the incidence of postoperative complications in laparoscopic liver resection

BACKGROUND

Liver fibrosis or cirrhosis frequently makes parenchymal transection more difficult, but the difficulty score of laparoscopic liver resection (LLR), including the IWATE criteria, does not include a factor related to liver fibrosis. Therefore, this study aimed to evaluate M2BPGi as a predictor of the difficulty of parenchymal transection and the incidence of postoperative complications in LLR.

METHODS

Data from 54 patients who underwent laparoscopic partial liver resection (LLR-P) and 24 patients who underwent laparoscopic anatomical liver resection between 2017 and 2019 in our institution were retrospectively analyzed. All cases were classified according to M2BPGi scores, and reserve liver function, intraoperative blood loss, and postoperative complications were compared among these groups.

RESULTS

Sixteen cases (29.6%) were M2BPGi negative (cut-off index < 1.0), 25 cases (46.3%) were 1+ (1.0 ≤ cut-off index < 3.0), and 13 cases (24.1%) were 2+ (cut-off index ≥ 3.0). M2BPGi-positive cases had significantly worse hepatic reserve function (K-ICG: 0.16 vs 0.14 vs 0.08, p < 0.0001). Intraoperative bleeding was significantly greater in M2BPGi-positive cases [50 ml vs 150 ml vs 200 ml, M2BPGi (-) or (1+) vs M2BPGi (2+), p = 0.045]. Postoperative complications (Clavien-Dindo ≥ II) were significantly more frequent in M2BPGi-positive cases [0% vs 4% vs 33%, M2BPGi (-) or (1+) vs M2BPGi (2+), p = 0.001].

CONCLUSION

M2BPGi could predict surgical difficulty and complications in LLR-P. In particular, it might be better not to select M2BPGi (2+) cases as teaching cases because of the massive bleeding during parenchymal transection.

Association of standardized liver volume and body mass index with outcomes of minimally invasive liver resections

INTRODUCTION

While minimally invasive liver resections (MILR) have demonstrated advantages in improved post-operative recovery, widespread adoption is hampered by inherent technical difficulties. Our study attempts to analyze the role of anthropometric measures in MILR-related outcomes.

METHODS

Between 2012 and 2020, 676 consecutive patients underwent MILR at the Singapore General Hospital of which 565 met study criteria and were included. Patients were stratified based on Body Mass Index (BMI) as well as Standardized Liver Volumes (SLV). Associations between BMI and SLV to selected peri-operative outcomes were analyzed using restricted cubic splines.

RESULTS

A BMI of ≥ 29 was associated with increase in blood loss [Mean difference (MD) 69 mls, 95% CI 2 to 137] as well as operative conversions [Relative Risk (RR) 1.63, 95% CI 1.02 to 2.62] among patients undergoing MILR while a SLV of 1600 cc or higher was associated with an increase in blood loss (MD 30 mls, 95% CI 10 to 49). In addition, a BMI of ≤ 20 was associated with an increased risk of major complications (RR 2.25, 95% 1.16 to 4.35). The magnitude of differences observed in these findings increased with each unit change in BMI and SLV.

CONCLUSION

Both BMI and SLV were useful anthropometric measures in predicting peri-operative outcomes in MILR and may be considered for incorporation in future difficulty scoring systems for MILR.

Utility of the Iwate difficulty scoring system for laparoscopic right posterior sectionectomy: do surgical outcomes differ for tumors in segments VI and VII?

INTRODUCTION

The Iwate Score (IS) have not been well-validated for specific procedures, especially for right posterior sectionectomy (RPS). In this study, the utility of the IS was determined for laparoscopic (L)RPS and the effect of tumor location on surgical outcomes was investigated.

METHODS

Post-hoc analysis of 647 L-RPS performed in 40 international centers of which 596L-RPS cases met the inclusion criteria. Baseline characteristics and perioperative outcomes of patients stratified based on the Iwate score were compared to determine whether a correlation with surgical difficulty existed. A 1:1 Mahalanobis distance matching was utilized to investigate the effect of tumor location on L-RPS outcomes.

RESULTS

The patients were stratified into 3 levels of difficulty (31 intermediate, 143 advanced, and 422 expert) based on the IS. When using a stepwise increase of the IS excluding the tumor location score, only Pringle's maneuver was more frequently used in the higher surgical difficulty level (35.5%, 54.6%, and 65.2%, intermediate, advanced, and expert levels, respectively, Z = 3.34, p = 0.001). Other perioperative results were not associated with a statistical gradation toward higher difficulty level. 80 of 85 patients with a segment VI lesion and 511 patients with a segment VII lesion were matched 1:1. There were no significant differences in the perioperative outcomes of the two groups including open conversion, operating time, blood loss, intraoperative blood transfusion, postoperative stay, major morbidity, and mortality.

CONCLUSION

Among patients undergoing L-RPS, the IS did not significantly correlate with most outcome measures associated with intraoperative difficulty and postoperative outcomes. Similarly, tumor location had no effect on L-RPS outcomes.

Poor utility of current nomograms assessing the risk of intraoperative blood transfusion in patients undergoing liver resection for hepatocellular carcinoma and proposal of a new model

BACKGROUND

The Memorial Sloan Kettering Cancer Center nomogram, the predictive scoring system of Yamamoto et al, and the 3-point transfusion risk score of Lemke et al are models used to determine the probability of receiving intraoperative blood transfusion in patients undergoing liver resection. However, the external validity of these models remains unknown. The objective of this study was to evaluate their predictive performance in an external cohort of patients with hepatocellular carcinoma. We also aimed to identify predictors of blood transfusion and develop a new predictive model for blood transfusion.

METHODS

Post hoc analysis of our prospective database of 1,081 patients undergoing liver resection for hepatocellular carcinoma from 2001 to 2018. The predictive performance of current prediction models was evaluated using C statistics. Demographic and clinical variables as predictors of blood transfusion were assessed. Using logistic regression, an alternative model was created.

RESULTS

The Lemke transfusion risk score performed better than the Memorial Sloan Kettering Cancer Center nomogram (0.69, 95% confidence interval 0.66-0.73 vs 0.66, 95% liver resection 0.62-0.69) (P < .001). The model from Yamamoto et al performed comparably with no statistically significant differences found through pairwise comparison. In our alternative model, hemoglobin level, albumin level, liver resection type, and tumor size were independent predictors of blood transfusion. The new HATS model obtained a C statistic of 0.74 (95% confidence interval 0.71-0.78), performing significantly better than the previous 3 models (P ≤ 0.001 for all).

CONCLUSION

The existing Memorial Sloan Kettering Cancer Center, Yamamoto et al, and Lemke et al had nomograms with the suboptimal accuracy of predicting risk of intraoperative blood transfusion in patients undergoing liver resection for hepatocellular carcinoma. The proposed HATS model was more accurate at predicting patients at risk of blood transfusion.

Robotic liver resection for hepatocellular carcinoma: analysis of surgical margins and clinical outcomes from a western tertiary hepatobiliary center

This study was undertaken to determine surgical outcomes of patients undergoing robotic hepatectomy for hepatocellular carcinoma (HCC) and to investigate the correlation between tumor distance to margin and perioperative outcomes, as well as overall survival (OS). To our knowledge, this study represents the largest series of robotic liver resection for HCC in North America. We retrospectively analyzed 58 consecutive patients who underwent robotic liver resection for HCC. Patients were further stratified by tumor distance to margin (≤ 1 mm, 1.1-9.9 mm, ≥ 10 mm) and their clinical outcomes including OS were compared. A majority of patients attained a greater than 1 mm tumor distance to margin (81%). There were no differences in tumor size between patient cohorts who attained ≤ 1 mm, 1.1-9.9 mm, and ≥ 10 mm margins. There were no differences in pre-, intra-, and postoperative outcomes among the three cohorts. Cost variables of interest were also similar. OS was highest in the > 10 mm margin cohort, and this was statistically significant at 3 and 5 years. Robotic HCC resection was associated with adequate tumor distance to margin. Wide margins ≥ 10 mm are associated with the best OS.

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 < 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 < 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.

Risk factors for and management of morbidity in pure laparoscopic resection of the right posterosuperior segments of the liver: A multicenter retrospective study

BACKGROUND

This study aimed to determine the risk factors for severe postoperative complications in patients undergoing pure laparoscopic liver resection (LLR) for tumors in the right posterosuperior (PS) segments.

METHODS

The study included 289 patients who underwent parenchyma-sparing pure LLR for tumors in the right PS segments at eight treatment centers between January 2009 and December 2019.

RESULTS

Multivariate analysis revealed tumor size ≥3 cm (P = .016), segmentectomy (P = .044), and liver cirrhosis (P = .029) as independent risk factors for severe postoperative complications. The severe complication rates (2.7% vs 12.1%, P = .0025), median intraoperative blood loss (100 mL vs 150 mL, P = .001), and median operation time (248 minutes vs 299.5 minutes, P = .0013) were lower in the patients without all these three risk factors than those with at least one risk factor. The median length of postoperative hospital stay was shorter in patients with no risk factors than those with at least one risk factor (9 days vs. 10 days, P = .001).

CONCLUSIONS

Tumor size ≥3 cm, segmentectomy, and liver cirrhosis were the risk factors for severe postoperative complications after parenchyma-sparing pure LLR for tumors in the right PS segments. Patients without these three risk factors would be appropriate candidates for safely performing parenchyma-sparing pure LLR in the right PS segments at the outset.

Laparoscopic versus open caudate lobe liver resections: a 1:2 propensity score-matched controlled study based on a single institution experience

BACKGROUND

Despite the wide use of laparoscopy for liver resection, laparoscopic caudate lobe resections(L-CLR) remain technically challenging, only attempted by experts in the field. The primary objective of this study was to determine the safety and compare the perioperative outcomes of L-CLR with O-CLR based on our single institution experience in a 1:2 propensity score-matched controlled study based on our single institution experience.

METHODS

Between 2004 and 2020, 67 consecutive patients who underwent CLR at Singapore General Hospital were identified. Propensity score matching (PSM) of laparoscopic versus open caudate lobe resections(O-CLR) was performed in a 1:2 ratio with no replacements using nearest neighbour matching method.

RESULTS

L-CLR was associated with a significantly decreased median blood loss (150 mL versus 500 mL, P = 0.001) and a decreased median post-operative stay (3 days versus 7.5 days, P = <0.01) in the unmatched cohorts. After 1:2 propensity score matching, these results were again demonstrated with a significantly lower blood loss (150 mL versus 400 mL, P = 0.016) and a shorter postoperative stay (3 days versus 7 days, P = <0.01) in favour of L-CLR. 30-day readmission and major morbidity (Clavien-Dindo grade > 2) rates were all in favour of L-CLR as well but could not reach statistical significance.

CONCLUSION

L-CLR can be safely performed by experienced surgeons. It is associated with decreased blood loss and shorter perioperative stay compared to O-CLR.

Impact of introduction of an enhanced recovery protocol on the outcomes of laparoscopic liver resections: A propensity-score matched study

BACKGROUND

Presently, data on the impact of enhanced recovery protocols on the outcomes of laparoscopic liver resection remain limited. We performed propensity matched analysis comparing the outcomes between patients undergoing laparoscopic liver resection before and after the introduction of an enhanced recovery protocol.

METHODS

Between 2013 and 2019, 462 consecutive patients underwent laparoscopic liver resection by 3 surgeons of which 360 met the study inclusion criteria. There were 89 patients who underwent surgery under an enhanced recovery protocol and 271 without an enhanced recovery protocol. One-to-one propensity matched analysis was performed for 84 enhanced recovery protocol patients and 84 nonenhanced recovery protocol patients.

RESULTS

Comparisons between propensity matched cohorts revealed that patients who received laparoscopic liver resection with enhanced recovery protocol had reduced median blood loss (200 vs 300 mL, P = .013), postoperative stay (3 vs 4 days, P = .003), and lower open conversion rates (0% vs 8.3%, P = .008). There was no difference in other key perioperative outcomes such as operation time, postoperative morbidity, postoperative major morbidity, and 30-day readmission rates.

CONCLUSION

A combined approach of enhanced recovery protocol and laparoscopic liver resection was associated with improved perioperative outcomes as opposed to laparoscopic liver resection alone.

Laparoscopic versus open resection of hepatocellular carcinoma in patients with cirrhosis: a meta-analysis

BACKGROUND

The exact role of laparoscopic liver resection (LLR) in patients with hepatocellular carcinoma (HCC) and underlying liver cirrhosis (LC) is not well defined. In this meta-analysis, both long- and short-term outcomes following LLR versus open liver resection (OLR) were analysed.

METHODS

PubMed, EMBASE, Scopus and Web of Science databases were searched systematically for randomised controlled trials (RCTs) and propensity-score matched (PSM) studies reporting outcomes of LLR versus OLR of HCC in patients with cirrhosis. Primary outcome was overall survival (OS). This was analysed using one-stage (individual participant data meta-analysis) and two-stage (aggregate data meta-analysis) approaches. Secondary outcomes were operation duration, blood loss, blood transfusion, Pringle manoeuvre utilization, overall and major complications, length of hospital stay (LOHS), 90-day mortality and R0 resection rates.

RESULTS

Eleven studies comprising 1618 patients (690 LLR versus 928 OLR) were included for analysis. In the one-stage meta-analysis, an approximately 18.7 per cent lower hazard rate (HR) of death in the LLR group (random effects: HR 0.81, 95 per cent confidence interval [C.I.] 0.68 to 0.96; P = 0.018) was observed. Two-stage meta-analysis resulted in a pooled HR of 0.84 (95 per cent C.I. 0.74 to 0.96; P = 0.01) in the overall LLR cohort. This indicated a 16-26 per cent reduction in the HR of death for patients with HCC and cirrhosis who underwent LLR. For secondary outcomes, LLR was associated with less blood loss (mean difference [MD] -99 ml, 95 per cent C.I. -182 to -16 ml), reduced overall complications (odds ratio 0.49, 95 per cent C.I. 0.37 to 0.66) and major complications (odds ratio 0.45, 95 per cent C.I. 0.26 to 0.79), and shorter LOHS (MD -3.22 days, 95 per cent C.I. -4.38 to -2.06 days).

CONCLUSION

Laparoscopic resection of HCC in patients with cirrhosis is associated with improved survival and perioperative outcomes.

Evolution and trends in the adoption of laparoscopic liver resection in Singapore: Analysis of 300 cases

ABSTRACT Introduction: The introduction of laparoscopic surgery has changed abdominal surgery. We evaluated the evolution and changing trends associated with adoption of laparoscopic liver resection (LLR) and the experience of a surgeon without prior LLR experience. Methods: A retrospective review of 310 patients who underwent LLR performed by a single surgeon from 2011 to 2020 was conducted. Exclusion criteria were patients who underwent laparoscopic liver surgeries such as excision biopsy, local ablation, drainage of abscesses and deroofing of liver cysts. There were 300 cases and the cohort was divided into 5 groups of 60 patients. Results: There were 288 patients who underwent a totally minimally invasive approach, including 28 robotic-assisted procedures. Open conversion occurred for 13 (4.3%) patients; the conversion rate decreased significantly from 10% in the initial period to 3.3% subsequently. There were 83 (27.7%) major resections and 131 (43.7%) resections were performed for tumours in the difficult posterosuperior location. There were 152 (50.7%) patients with previous abdominal surgery, including 52 (17.3%) repeat liver resections for recurrent tumours, and 60 patients had other concomitant operations. According to the Iwate criteria, 135 (44.7%) were graded as high/expert difficulty. Major morbidity (>grade 3a) occurred in 12 (4.0%) patients and there was no 30-day mortality. Comparison across the 5 patient groups demonstrated a significant trend towards older patients, higher American Society of Anesthesiologists (ASA) score, increasing frequency of LLR with previous abdominal surgery, increasing frequency of portal hypertension and huge tumours, decreasing blood loss and decreasing transfusion rate across the study period. Surgeon experience (≤60 cases) and Institut Mutualiste Montsouris (IMM) high grade resections were independent predictors of open conversion. Open conversion was associated with worse perioperative outcomes such as increased blood loss, transfusion rate, morbidity and length of stay. Conclusion: LLR can be safely adopted for resections of all difficulty grades, including major resections and for tumours located in the difficult posterosuperior segments, with a low open conversion rate. Keywords: Laparoscopic hepatectomy, laparoscopic liver resection, robotic hepatectomy, robotic liver resection, Singapore

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.

Impact of smoking on weight loss outcomes after bariatric surgery: a literature review

BACKGROUND

The association between smoking and surgical complications after bariatric surgery has been well-established. However, given that this patient population is inherently weight-concerned, understanding the effects of tobacco use on postoperative weight loss is essential to guiding clinicians in counseling patients. We aimed to summarize the current literature examining the effects of preoperative and postoperative smoking, as well as changes in smoking status, on bariatric surgery weight loss outcomes.

METHODS

Ovid MEDLINE, PubMed, and SCOPUS databases were queried to identify relevant published studies.

RESULTS

Overall, 20 studies were included. Preoperative and postoperative smoking rates varied widely across studies, as did requirements for smoking cessation prior to bariatric surgery. Reported preoperative smoking prevalence ranged from 1 to 62%, and postoperative smoking prevalence ranged from 6 to 43%. The majority of studies which examined preoperative and/or postoperative smoking habits found no association between smoking habits and postoperative weight loss outcomes. A minority of studies found relatively small differences in postoperative weight loss between smokers and nonsmokers; these often became nonsignificant with longer follow-up. No studies found significant associations between changes in smoking status and weight loss outcomes.

CONCLUSION

While smoking has been associated with weight loss in the general population, most current evidence demonstrates that smoking habits are not associated with weight loss outcomes after bariatric surgery. However, due to the heterogeneity in study design and analysis, no definitive conclusions can be made, and more robust studies are needed to investigate any relationship between smoking and long-term weight loss outcomes. Given the established increased risk of surgical complications and mortality in smokers, smoking cessation should be encouraged.

Laparoscopic liver resection for huge (≥10 cm) hepatocellular carcinoma: A coarsened exact-matched single-surgeon study

INTRODUCTION

Laparoscopic liver resection (LLR) is increasingly being utilised worldwide for the management of both benign and malignant liver tumours. However, there is limited data to date regarding the safety and feasibility of this approach for huge (≥10 cm) hepatocellular carcinomas (HCCs). We present here our early experience performing LLR for huge HCCs.

METHODS

We conducted a retrospective review of 280 consecutive patients who underwent LLR by a single surgeon from 2012 to August 2020.15 patients had a preoperative radiological diagnosis of huge (≥10 cm) HCC. Coarsened exact-matched (CEM) weighting was used to compare them to 101 patients who underwent LLR for non-huge HCC.

RESULTS

After CEM-weighting, both groups were well-balanced for baseline variables. There was no difference in the rates of open conversion. The huge HCC patients had a higher mean Iwate difficulty score than the non-huge HCC patients (9.13 vs 6.53, p = 0.007). As such, the median operating time for the huge HCC group was longer (360 min vs 240min, p = 0.049). However, there were no significant differences in estimated blood loss, proportion of patients requiring blood transfusion, utilization of Pringle maneuver or median Pringle duration. Post-operatively, there were no significant differences in median LOS, overall and major morbidity rates, and 90-day mortality rates between both groups. Median resection margins were also similar for both cohorts.

CONCLUSION

LLR may be performed successfully for selected patients with huge HCC, with encouraging perioperative outcomes and no compromise in oncologic efficacy.