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.

Defining Global Benchmarks for Laparoscopic Right Posterior Sectionectomy/H67: An International Multicenter Study.

OBJECTIVE: We aimed to establish global benchmark outcomes indicators for L-RPS/H67. BACKGROUND: Minimally invasive liver resections has seen an increase in uptake in recent years. Over time, challenging procedures as laparoscopic right posterior sectionectomies (L-RPS)/H67 are also increasingly adopted. METHODS: This is a post hoc analysis of a multicenter database of 854 patients undergoing minimally invasive RPS (MI-RPS) in 57 international centers in 4 continents between 2015 and 2021. There were 651 pure L-RPS and 160 robotic RPS (R-RPS). Sixteen outcome indicators of low-risk L-RPS cases were selected to establish benchmark cutoffs. The 75th percentile of individual center medians for a given outcome indicator was set as the benchmark cutoff. RESULTS: There were 573 L-RPS/H67 performed in 43 expert centers, of which 254 L-RPS/H67 (44.3%) cases qualified as low risk benchmark cases. The benchmark outcomes established for operation time, open conversion rate, blood loss ≥500 mL, blood transfusion rate, postoperative morbidity, major morbidity, 90-day mortality and textbook outcome after L-RPS were 350.8 minutes, 12.5%, 53.8%, 22.9%, 23.8%, 2.8%, 0% and 4% respectively. CONCLUSIONS: The present study established the first global benchmark values for L-RPS/H6/7. The benchmark provided an up-to-date reference of best achievable outcomes for surgical auditing and benchmarking.

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.

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.

Explainable artificial intelligence prediction-based model in laparoscopic liver surgery for segments 7 and 8: an international multicenter study.

BACKGROUND: Artificial intelligence (AI) is becoming more useful as a decision-making and outcomes predictor tool. We have developed AI models to predict surgical complexity and the postoperative course in laparoscopic liver surgery for segments 7 and 8. METHODS: We included patients with lesions located in segments 7 and 8 operated by minimally invasive liver surgery from an international multi-institutional database. We have employed AI models to predict surgical complexity and postoperative outcomes. Furthermore, we have applied SHapley Additive exPlanations (SHAP) to make the AI models interpretable. Finally, we analyzed the surgeries not converted to open versus those converted to open. RESULTS: Overall, 585 patients and 22 variables were included. Multi-layer Perceptron (MLP) showed the highest performance for predicting surgery complexity and Random Forest (RF) for predicting postoperative outcomes. SHAP detected that MLP and RF gave the highest relevance to the variables "resection type" and "largest tumor size" for predicting surgery complexity and postoperative outcomes. In addition, we explored between surgeries converted to open and non-converted, finding statistically significant differences in the variables "tumor location," "blood loss," "complications," and "operation time." CONCLUSION: We have observed how the application of SHAP allows us to understand the predictions of AI models in surgical complexity and the postoperative outcomes of laparoscopic liver surgery in segments 7 and 8.

Short-term outcomes of laparoscopic extended hepatectomy versus major hepatectomy: a single-center experience.

INTRODUCTION: Laparoscopic major hepatectomy (LMH) remains restricted to a few specialized centers and poses a challenge to surgeons performing laparoscopic resections. Laparoscopic extended resections are even more complex and rarely conducted. METHODS: From a single-institution database, we compared the short-term outcomes of patients who underwent major and extended laparoscopic resections, stratifying the entire retrospective cohort into four groups: right hepatectomy, left hepatectomy, right extended hepatectomy, and left extended hepatectomy. Patient demographics, tumor characteristics, operative variables, and especially postoperative outcomes were evaluated. RESULTS: 250 patients underwent major and extended laparoscopic liver resections, including 160 right, 31 right extended, 36 left, and 23 left extended laparoscopic hepatectomies. The most common indication for resection was colorectal liver metastases (64%). Laparoscopic extended hepatectomy (LEH) showed significantly longer operative time, more blood loss, need for Pringle maneuver, conversion to open surgery, higher rates of liver failure, postoperative ascites, and intra-abdominal hemorrhage, R1 margins and length of stay when compared with the LMH group. Mortality rates were similar between groups. Multivariate analysis revealed intraoperative blood transfusion (OR = 5.1[CI-95%: 1.15-6.79]; p = 0.02) as an independent predictor for major complications. CONCLUSIONS: LEH showed to be feasible, however with higher blood loss and significantly associated to major complications.

Defining Global Benchmarks for Laparoscopic Liver Resections: An International Multicenter Study.

OBJECTIVE: To establish global benchmark outcomes indicators after laparoscopic liver resections (L-LR). BACKGROUND: There is limited published data to date on the best achievable outcomes after L-LR. METHODS: This is a post hoc analysis of a multicenter database of 11,983 patients undergoing L-LR in 45 international centers in 4 continents between 2015 and 2020. Three specific procedures: left lateral sectionectomy (LLS), left hepatectomy (LH), and right hepatectomy (RH) were selected to represent the 3 difficulty levels of L-LR. Fifteen outcome indicators were selected to establish benchmark cutoffs. RESULTS: There were 3519 L-LR (LLS, LH, RH) of which 1258 L-LR (40.6%) cases performed in 34 benchmark expert centers qualified as low-risk benchmark cases. These included 659 LLS (52.4%), 306 LH (24.3%), and 293 RH (23.3%). The benchmark outcomes established for operation time, open conversion rate, blood loss ≥500 mL, blood transfusion rate, postoperative morbidity, major morbidity, and 90-day mortality after LLS, LH, and RH were 209.5, 302, and 426 minutes; 2.1%, 13.4%, and 13.0%; 3.2%, 20%, and 47.1%; 0%, 7.1%, and 10.5%; 11.1%, 20%, and 50%; 0%, 7.1%, and 20%; and 0%, 0%, and 0%, respectively. CONCLUSIONS: This study established the first global benchmark outcomes for L-LR in a large-scale international patient cohort. It provides an up-to-date reference regarding the "best achievable" results for L-LR for which centers adopting L-LR can use as a comparison to enable an objective assessment of performance gaps and learning curves.

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.

Impact of Tumor Size on the Difficulty of Laparoscopic Major Hepatectomies: An International Multicenter Study.

INTRODUCTION: Although tumor size (TS) is known to affect surgical outcomes in laparoscopic liver resection (LLR), its impact on laparoscopic major hepatectomy (L-MH) is not well studied. The objectives of this study were to investigate the impact of TS on the perioperative outcomes of L-MH and to elucidate the optimal TS cutoff for stratifying the difficulty of L-MH. METHODS: This was a post-hoc analysis of 3008 patients who underwent L-MH at 48 international centers. A total 1396 patients met study criteria and were included. The impact of TS cutoffs was investigated by stratifying TS at each 10-mm interval. The optimal cutoffs were determined taking into consideration the number of endpoints which showed a statistically significant split around the cut-points of interest and the magnitude of relative risk after correction for multiple risk factors. RESULTS: We identified 2 optimal TS cutoffs, 50 mm and 100 mm, which segregated L-MH into 3 groups. An increasing TS across these 3 groups (≤ 50 mm, 51-100 mm, > 100 mm), was significantly associated with a higher open conversion rate (11.2%, 14.7%, 23.0%, P < 0.001), longer operating time (median, 340 min, 346 min, 365 min, P = 0.025), increased blood loss (median, 300 ml,  ml, 400 ml, P = 0.002) and higher rate of intraoperative blood transfusion (13.1%, 15.9%, 27.6%, P < 0.001). Postoperative outcomes such as overall morbidity, major morbidity, and length of stay were comparable across the three groups. CONCLUSION: Increasing TS was associated with poorer intraoperative but not postoperative outcomes after L-MH. We determined 2 TS cutoffs (50 mm and 10 mm) which could optimally stratify the surgical difficulty of L-MH.

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.

Long-term oncological outcomes for HALS/Hybrid vs pure laparoscopic approach in colorectal liver metastases: a propensity score matched analysis.

BACKGROUND: Studies comparing hand-assisted laparoscopic (HALS)/Hybrid and pure laparoscopic (PLS) resection for colorectal cancer liver metastasis have focused on short-term results, while long-term oncological outcomes remain understudied. METHODS: We established a multi-institutional retrospective cohort study from four centers with experience in minimally invasive surgery between 2004 and 2020. Primary endpoints were overall survival (OS) and disease-free survival (DFS). Other endpoints analyzed were intraoperative and postoperative outcomes. Propensity score matching (PSM) was used to minimize baseline differences. RESULTS: A total of 219 HALS/Hybrid (57.8%) and 160 PLS (42.2%) patients were included. After PSM, 155 patients remained in each group. Operative time (182 vs. 248 min, p = 0.012), use of intraoperative ablation (12.3 vs. 4.5%, p = 0.024), positive resection margin (4.5 vs 13.2%, p = 0.012), and pringle time (21 vs. 37 min, p = 0.001) were higher in PLS group. DFS at 1, 3, 5, and 7 years in HALS/Hybrid and PLS groups were 65.4%, 39.3%, 37.5%, and 36.3% vs. 64.9%, 38.0%, 33.1%, and 33.1%, respectively (p = 0.84). OS at 1, 3, 5, and 7 years in HALS/Hybrid and PLS groups were 94.5%, 71.4%, 54.3%, and 46.0% vs. 96.0%, 68.5%, 51.2%, and 41.2%, respectively (p = 0.73). CONCLUSION: Our study suggests no differences in long-term oncologic outcomes between the two techniques. We discovered that longer total operative, pringle time, higher rates of intraoperative ablation, and positive resection margins were associated with PLS. These differences in favor of HALS/Hybrid could be due to a shorter learning curve and a greater ability to control hemorrhage.

Robotic versus laparoscopic liver resections for hepatolithiasis: an international multicenter propensity score matched analysis.

INTRODUCTION: Minimally invasive liver resection (MILR) is widely recognized as a safe and beneficial procedure in the treatment of both malignant and benign liver diseases. Hepatolithiasis has traditionally been reported to be endemic only in East Asia, but has seen a worldwide uptrend in recent decades with increasingly frequent and invasive endoscopic instrumentation of the biliary tract for a myriad of conditions. To date, there has been a woeful lack of high-quality evidence comparing the laparoscopic (LLR) and robotic (RLR) approaches to treatment hepatolithiasis. METHODS: This is an international multicenter retrospective analysis of 273 patients who underwent RLR or LRR for hepatolithiasis at 33 centers in 2003-2020. The baseline clinicopathological characteristics and perioperative outcomes of these patients were assessed. To minimize selection bias, 1:1 (48 and 48 cases of RLR and LLR, respectively) and 1:2 (37 and 74 cases of RLR and LLR, respectively) propensity score matching (PSM) was performed. RESULTS: In the unmatched cohort, 63 (23.1%) patients underwent RLR, and 210 (76.9%) patients underwent LLR. Patient clinicopathological characteristics were comparable between the groups after PSM. After 1:1 and 1:2 PSM, RLR was associated with less blood loss (p = 0.003 in 1:2 PSM; p = 0.005 in 1:1 PSM), less patients with blood loss greater than 300 ml (p = 0.024 in 1:2 PSM; p = 0.027 in 1:1 PSM), and lower conversion rate to open surgery (p = 0.003 in 1:2 PSM; p < 0.001 in 1:1 PSM). There was no significant difference between RLR and LLR in use of the Pringle maneuver, median Pringle maneuver duration, 30-day readmission rate, postoperative morbidity, major morbidity, reoperation, and mortality. CONCLUSION: Both RLR and LLR were safe and feasible for hepatolithiasis. RLR was associated with significantly less blood loss and lower open conversion rate.

A core set of quality performance indicators for HPB procedures: a global consensus for hepatectomy, pancreatectomy, and complex biliary surgery.

BACKGROUND: Surgery for hepatopancreaticobiliary (HPB) conditions is performed worldwide. This investigation aimed to develop a set of globally accepted procedural quality performance indicators (QPI) for HPB surgical procedures. METHODS: A systematic literature review generated a dataset of published QPI for hepatectomy, pancreatectomy, complex biliary surgery and cholecystectomy. Using a modified Delphi process, three rounds were conducted with working groups composed of self-nominating members of the International Hepatopancreaticobiliary Association (IHPBA). The final set of QPI was circulated to the full membership of the IHPBA for review. RESULTS: Seven "core" indicators were agreed for hepatectomy, pancreatectomy, and complex biliary surgery (availability of specific services on site, a specialised surgical team with at least two certified HPB surgeons, a satisfactory institutional case volume, synoptic pathology reporting, undertaking of unplanned reintervention procedures within 90 days, the incidence of post-procedure bile leak and Clavien-Dindo grade ≥III complications and 90-day post-procedural mortality). Three further procedure specific QPI were proposed for pancreatectomy, six for hepatectomy and complex biliary surgery. Nine procedure-specific QPIs were proposed for cholecystectomy. The final set of proposed indicators were reviewed and approved by 102 IHPBA members from 34 countries. CONCLUSIONS: This work presents a core set of internationally agreed QPI for HPB surgery.

Non-Alcoholic Fatty Liver Disease-Related Hepatocellular Carcinoma: Immunohistochemical Assessment of Markers of Cancer Cell Metabolism.

INTRODUCTION: Hepatocellular carcinoma (HCC) has been associated to non-alcoholic fatty liver disease (NAFLD). We sought to investigate the immunoexpression of several glycolytic metabolism-associated markers in patients with HCC associated to NAFLD and associate these factors to their clinical-pathological characteristics. METHODS: We evaluated 35 HCC specimens from 21 patients diagnosed with non-alcoholic steatohepatitis (NASH) undergoing liver resection (12 patients), liver transplantation (8 patients), or both (1 patient). Histological features, clinical aspects, demographic and biochemical data, as well as the immunohistochemical reactivity for monocarboxylate transporters 1, 2, and 4; their chaperone CD147; carbonic anhydrase IX; and glucose transporter-1 (GLUT1) were assessed. RESULTS: Metabolic-associated cirrhosis was present in 12 of the 21 patients (8 child A and 4 child B scores). From 9 patients without cirrhosis, 3 presented NASH F3 and 6 NASH F2. Sixteen (76%) had diabetes mellitus, 17 (81%) arterial hypertension, and 19 (90%) body mass index above 25 kg/m2; 8 (38%) had dyslipidemia. From 35 nodules, steatosis was found in 26, ballooning in 31 nodules, 25 of them diagnosed as steatohepatitic subtype of HCC. MCT4 immunoexpression was associated with extensive intratumoral fibrosis, advanced clinical stages, and shorter overall survival. GLUT1 was noticeable in nodules with extensive intratumoral steatosis, higher intratumoral fibrosis, and advanced clinical stages. Immunohistochemical expression of the metabolic biomarkers MCT4 and GLUT1 was higher in patients with Barcelona-clinic liver cancer B or C. GLUT1 correlated with higher degree of steatosis, marked ballooning, intratumoral fibrosis, and higher parenchymal necroinflammatory activity. CONCLUSION: Our data indicate that the expression of the glycolytic phenotype of metabolic markers, especially GLUT1 and MCT4, correlates with a more severe course of HCC occurring in NASH patients.

Liver Surgery: Important Considerations for Pre- and Postoperative Imaging.

Liver surgery may be a curative treatment option not only for primary liver neoplasms but also for liver metastases in selected patients. The number of liver surgeries performed worldwide has increased, but surgical morbidity associated with these surgeries remains significant. Therefore, radiologists need to understand the terminology, surgical techniques, resectability and unresectability criteria, and possible postoperative complications as these are part of the decision-making process. Because vascular and biliary variations are common, an adequate preoperative anatomic evaluation determines the best surgical technique, helps identify patients in whom additional surgical steps will be required, and reduces the risk of inadvertent injury. The surgeon must ensure that the future liver remnant is sufficient to maintain adequate function, aided by the radiologist who can provide valuable information such as the presence of steatosis, biliary dilatation, signs of cirrhosis, and portal hypertension, in addition to the volume of the future liver remnant. Postoperative complications must also be understood and evaluated. The most common postoperative complications are vascular (bleeding, thrombosis, and ischemia), biliary (fistulas, bilomas, and strictures), infectious (incisional or deep), those related to liver failure, and even tumor recurrence. An invited commentary by Winslow is available online. Online supplemental material is available for this article. ©RSNA, 2022.

Repeat hepatectomy for recurrent colorectal liver metastases: A comparative analysis of short- and long-term results.

BACKGROUND: Liver recurrence after resection of colorectal liver metastases (CRLM) is frequent. Repeat hepatectomy has been shown to have satisfactory perioperative results. However, the long-term outcomes and the benefits for patients with early recurrence have not been clarified. The aim of this study was to compare the short- and long-term outcomes of patients undergoing single hepatectomy and repeat hepatectomy for CRLM. Additionally, the oncological outcomes of patients with early (≤ 6 months) and late recurrence who underwent repeat hepatectomy were compared. METHODS: Consecutive adult patients undergoing hepatectomy for CRLM between June 2000 and February 2020 were included and divided into two groups: single hepatectomy and repeat hepatectomy. RESULTS: A total of 709 patients were included: 649 in the single hepatectomy group and 60 in the repeat hepatectomy group. Patients in the repeat hepatectomy group underwent more cycles of preoperative chemotherapy [4 (3-6) vs. 3 (2-4), P = 0.003]. Patients in the single hepatectomy group more frequently underwent major hepatectomies (34.5% vs. 16.7%, P = 0.004) and had a greater number of lesions resected (2.9 ± 3.6 vs. 1.9 ± 1.8, P = 0.011). There was no increase in operative time, estimated blood loss, length of hospital stay, complications, or mortality in the repeat hepatectomy group. There were no differences in overall survival (P = 0.626) and disease-free survival (P = 0.579) between the two groups. Similarly, for patients underwent repeat hepatectomy, no difference was observed between the early and late recurrence groups in terms of overall survival (P = 0.771) or disease-free survival (P = 0.350). CONCLUSIONS: Repeat hepatectomy is feasible and safe, with similar short- and long-term outcomes when compared to single hepatectomy. Surgical treatment of early liver recurrence offers similar oncological outcomes to those obtained for late recurrence.

Preoperative inflammatory markers as prognostic predictors after hepatocellular carcinoma resection: data from a western referral center.

BACKGROUND: Recent studies from eastern centers have demonstrate an association between inflammatory response and long-term outcomes after hepatocellular carcinoma (HCC) resection. However, the prognostic impact of inflammatory markers in western patients, with distinct tumor and epidemiologic features, is still unknown. AIM: To evaluate the prognostic impact of preoperative neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR), as well as their impact according to tumor size (< 5 cm, 5-10 cm, > 10 cm) in patients undergoing HCC resection with curative intent. METHODS: Optimal cut-off values for NLR, PLR, and MLR were determined by plotting the receiver operator curves. Overall survival (OS) and disease-free survival (DFS) curves were calculated using the Kaplan-Meier method and compared using the log-rank test. The Cox method was used to identify independent predictors of OS and DFS. RESULTS: In total, 161 consecutive adult patients were included. A high NLR (> 1.715) was associated with worse OS (P = 0.018). High NLR (> 2.475; P = 0.047) and PLR (> 100.25; P = 0.028) were predictors of short DFS. In HCC < 5 cm, MLR (> 1.715) was associated with worse OS (P = 0.047). In the multivariate analysis, high PLR was an independent predictor of worse DFS [hazard ratio (HR) 3.029; 95%CI 1.499-6.121; P = 0.002]. CONCLUSION: Inflammatory markers are useful tools to predict long-term outcomes after liver resection in western patients, high NLR was able to stratify subgroups of patients with short OS and DFS, an increased PLR was an independent predictor of short DFS, while high MLR was associated with short OS in patients with early HCC.

Infiltrative Tumor Borders in Colorectal Liver Metastasis: Should We Enlarge Margin Size?

BACKGROUND: Surgery is the only potentially curative treatment for colorectal cancer liver metastases (CRLMs). Despite an improvement in results following resection, recurrence rates remain high. Many histopathological features have been reported as prognostic factors. Infiltrative borders are known to be associated with worse prognosis; however, margin size has never been evaluated together with the type of tumor border. In the present study, we analyzed the prognosis of patients with resected CRLM according to tumor growth pattern (TGP) and whether a larger margin size would bring any prognostic benefit. PATIENTS AND METHODS: Medical records from a prospective database of 645 patients who underwent hepatic resection for CRLM between January 2004 and December 2019 at a single center were reviewed, and 266 patients were included in the analytic cohort. TGP (pushing or infiltrative) was evaluated regarding the impact in overall and disease-free survival. The impact of margin size (≤ or > 1 cm) on survival and hepatic recurrence according to TGP was also evaluated. RESULTS: TGP was defined as infiltrative in 182 cases (68.4%) and pushing in 84 patients (31.6%). Patients with infiltrative-type border presented worse overall survival and disease-free survival, as well as higher intrahepatic recurrence (p < 0.05). Larger margin size did not impact the prognosis of patients with infiltrative borders. CONCLUSIONS: Patients with infiltrative-type border present worse prognosis and higher intrahepatic recurrence. Larger margin size (> 1 cm) does not change the prognosis in patients with infiltrative border, showing that tumor biology is the most important factor for survival.

Combined liver and multivisceral resections: A comparative analysis of short and long-term outcomes.

BACKGROUND: En bloc liver and adjacent organs resections are technically demanding procedures. Few case series and nonmatched comparative studies reported the outcomes of multivisceral liver resections (MLRs). OBJECTIVES: To compare the short and long-term outcomes of patients submitted MLRs with those submitted to isolated hepatectomies. METHODS: From a prospective database, a case-matched 1:2 study was performed comparing MLRs and isolated hepatectomy. Additionally, a risk analysis was performed to evaluate the association between MLRs and perioperative morbidity, mortality, and long-term survival. RESULTS: Fifty-three MLRs were compared with 106 matched controls. Patients undergoing MLRs had longer operative time (430 [320-525] vs 360 [270-440] minutes, P = .005); higher estimated blood loss (600 [400-800] vs 400 [100-600] mL; P = .011); longer hospital stay (8 [6-14] vs 7 [5-9] days; P = .003); and higher postoperative mortality (9.4% vs 1.9%, P = .042). Number of resected organs was not an independent prognostic factor for perioperative major complications (odds ratio [OR], 1 organ = 1.8 [0.54-6.05]; OR ≥ 2, organs = 4.0 [0.35-13.84]) or perioperative mortality (OR, 1, organ = 5.2 [0.91-29.51]; OR ≥ 2, organs = 6.5 [0.52-79.60]). No differences in overall (P = .771) and disease-free survival (P = .28) were observed. CONCLUSION: MLRs are feasible with acceptable morbidity but relatively high perioperative mortality. MLRs did not negatively affect long-term outcomes.

Minimally invasive versus open right hepatectomy: comparative study with propensity score matching analysis.

BACKGROUND: Minimally invasive liver resections (MILRs) have been increasingly performed in recent years. However, the majority of MILRs are actually minor or limited resections of peripheral lesions. Due to the technical complexity major hepatectomies remain challenging for minimally invasive surgery. The aim of this study was to compare the short and long-term outcomes of patients undergoing minimally invasive right hepatectomies (MIRHs) with contemporary patients undergoing open right hepatectomies (ORHs) METHODS: Consecutive patients submitted to anatomic right hepatectomies between January 2013 and December 2018 in two tertiary referral centers were studied. Study groups were compared on an intention-to-treat basis after propensity score matching (PSM). Overall survival (OS) analyses were performed for the entire cohort and specific etiologies subgroups RESULTS: During study period 178 right hepatectomies were performed. After matching, 37 patients were included in MIRH group and 60 in ORH group. The groups were homogenous for all baseline characteristics. MIRHs had significant lower blood loss (400 ml vs. 500 ml, P = 0.01), lower rate of minor complications (13.5% vs. 35%, P = 0.03) and larger resection margins (10 mm vs. 5 mm, P = 0.03) when compared to ORHs. Additionally, a non-significant decrease in hospital stay (ORH 9 days vs. MIRH 7 days, P = 0.09) was observed. No differences regarding the use of Pringle's maneuver, operative time, overall morbidity or perioperative mortality were observed. OS was similar between the groups (P = 0.13). Similarly, no difference in OS was found in subgroups of patients with primary liver tumors (P = 0.09) and liver metastasis (P = 0.80). CONCLUSIONS: MIRHs are feasible and safe in experienced hands. Minimally invasive approach was associated with less blood loss, a significant reduction in minor perioperative complications, and did not negatively affect long-term outcomes.