Minimally Invasive Liver Surgery Research Articles

What Is the Role of Minimally Invasive Liver Surgery in Treating Patients with Hepatocellular Carcinoma on Cirrhosis?

Minimally invasive liver surgery (MILS) has been slowly introduced in the past two decades and today represents a major weapon in the fight against HCC, for several reasons. This narrative review conveys the major emerging concepts in the field. The rise in metabolic-associated steatotic liver disease (MASLD)-related HCC means that patients with significant cardiovascular risk will benefit more profoundly from MILS. The advent of efficacious therapy is leading to conversion from non-resectable to resectable cases, and therefore more patients will be able to undergo MILS. In fact, resection outcomes with MILS are superior compared to open surgery both in the short and long term. Furthermore, indications to surgery may be further expanded by its use in Child B7 patients and by the use of laparoscopic ablation, a curative technique, instead of trans-arterial approaches in cases not amenable to radiofrequency. Therefore, in a promising new approach, multi-parametric treatment hierarchy, MILS is hierarchically superior to open surgery and comes second only to liver transplantation.

Concomitant training in robotic and laparoscopic liver resections of low-to-intermediate difficulty score: a retrospective analysis of the learning curve

In the setting of minimally invasive liver surgery (MILS), training in robotic liver resections (RLR) usually follows previous experience in laparoscopic liver resections (LLR). The aim of our study was to assess the learning curve of RLR in case of concomitant training with LLR. We analyzed consecutive RLRs and LLRs by a surgeon trained simultaneously in both techniques (Surg1); while a second surgeon trained only in LLRs was used as control (Surg2). A regression model was used to adjust for confounders and a Cumulative Sum (CUSUM) analysis was carried out to assess the learning phases according to operative time and difficulty of the procedures (IWATE score). Two-hundred-forty-five procedures were identified (RobSurg1, n = 75, LapSurg1, n = 102, LapSurg2, n = 68). Mean IWATE was 4.0, 4.3 and 5.8 (p < 0.001) in each group. The CUSUM analysis of the adjusted operative times estimated the learning phase in 40 cases (RobSurg1), 40 cases (LapSurg1), 48 cases (LapSurg2); for IWATE score it was 38 cases (RobSurg1), 33 cases (LapSurg1), 38 cases (LapSurg2) respectively. Our preliminary experience showed a similar learning curve of 40 cases for low and intermediate difficulty RLR and LLR. Concomitant training in both techniques was safe and may be a practical option for starting a MILS program.

Prevention of Post-Hepatectomy Liver Failure in Cirrhotic Patients Undergoing Minimally Invasive Liver Surgery for HCC: Has the Round Ligament to Be Preserved?

Post-hepatectomy liver failure (PHLF) represents a major cause of morbidity and mortality after liver resection. The factors related to PHLF are represented not only by the volume and function of the future liver remnant but also by the severity of portal hypertension. The aim of this study was to assess whether the preservation of the round ligament (RL) may mitigate portal hypertension, thus decreasing the risk of PHLF and ascites in cirrhotic patients while undergoing minimally invasive liver surgery (MILS). All the cirrhotic patients who underwent MILS for HCC from 2016 to 2021 in two international tertiary referral centers were retrospectively analyzed, comparing cases with the RL preserved vs. those with the RL divided. Only patients with cirrhosis ≥ Child A6, portal hypertension, and ICG-R15 > 10% were included. Main postoperative outcomes were compared, and the risk factors for postoperative ascites (severe PHLF, grade B/C) were investigated through a logistic regression. After the application of the selection criteria, a total of 130 MILS patients were identified, with 86 patients with the RL preserved and 44 with the RL divided. The RL-preserved group showed lower incidences of severe PHLF (7.0% vs. 20.5%, p = 0.023) and ascites (5.8% vs. 18.2%, p = 0.026) in comparison with the RL-divided group. After uni/multivariate analysis, the risk factors related to postoperative ascites were RL division and platelets < 92 × 103/µL, calculated with ROC analysis. The preservation of the round ligament during MILS may mitigate portal hypertension, preventing PHLF and ascites in cirrhotic patients with borderline liver function.

Global practice patterns of preoperative image reconstruction for liver surgery

BackgroundThree-dimensional (3-D) liver modeling is used globally; however, its actual practice is limited to a few centers. This study aimed to assess practice patterns and barriers to the use of 3-D modeling among liver surgeons worldwide. MethodsA survey approved by the International Hepato-Pancreato-Biliary Association research council consisting of 27 questions was conducted using an online questionnaire. Incomplete responses were excluded. ResultsOf 235 respondents from 46 countries, 81.3% reported experience with 3-D modeling; however, only 21% used it in > 75% of cases. Surgeons using 3-D reconstruction were older (P = .025), worked more frequently at academic facilities (P = .007), and had more years of experience (P = .001), especially in minimally invasive liver surgery (MILS) (P = .038). In addition, 3-D rendering was performed by surgeons in 50.8% of cases. Liver volumetry was the most frequent indication (80.1%), and decreased postoperative complications were the main perceived benefit (53.6%). ConclusionsMore experience in liver surgery because of seniority, case volume, and openness to novel technology (MILS) is associated with a greater appreciation for the value of 3-D modeling. Our results suggest the need for senior surgeons to help early-career surgeons consider 3-D modeling for the reported benefit of reduced intra- and postoperative complications.

Minimal Invasive Versus Open Surgery for Colorectal Liver Metastases: A Multicenter German StuDoQ|Liver Registry-Based Cohort Analysis in Germany.

To compare the outcome of minimally invasive liver surgery (MILS) to open liver surgery (OLS) for resection of colorectal liver metastases (CRLM) on a nationwide level. Colorectal cancer is the third most common malignancy worldwide. Up to 50% of all patients with colorectal cancer develop CRLM. MILS represents an attractive alternative to OLS for treatment of CRLM. Retrospective cohort study using the prospectively recorded German Quality management registry for liver surgery. Propensity-score matching was performed to account for variance in the extent of resection and patient demographics. In total, 1037 patients underwent liver resection for CRLM from 2019 to 2021. MILS was performed in 31%. Operative time was significantly longer in MILS (234 vs 222 minutes, P = 0.02) compared with OLS. After MILS, median length of hospital stay (LOS) was significantly shorter (7 vs 10 days; P < 0.001). Despite 76% of major resections being OLS, postoperative complications and 90-day morbidity and mortality did not differ. The Pringle maneuver was more frequently used in MILS (48% vs 40%, P = 0.048). After propensity-score matching for age, body mass index, Eastern Cooperative Oncology Group, and extent of resection, LOS remained shorter in the MILS cohort (6 vs 10 days, P < 0.001) and operative time did not differ significantly (P = 0.2). MILS is not the standard for resection of CRLM in Germany. Drawbacks, such as a longer operative time remain. However, if technically possible, MILS is a reasonable alternative to OLS for resection of CRLM, with comparable postoperative complications, reduced LOS, and equal oncological radicality.

Robotic versus laparoscopic liver resections: propensity-matched comparison of two-center experience.

The advantages of the robotic approach in minimally invasive liver surgery (MILS) are still debated. This study compares the short-term outcomes between laparoscopic (LLR) and robotic (RLR) liver resections in propensity score matched cohorts. Data regarding minimally invasive liver resections in two liver surgery units were retrospectively reviewed. A propensity score matched analysis (1:1 ratio) identified two groups of patients with similar characteristics. Intra- and post-operative outcomes were then compared. The difficulty of MILS was based on the IWATE criteria. Two hundred sixty-nine patients underwent MILS between January 2014 and December 2021 (LLR = 192; RLR = 77). Propensity score matching identified 148 cases (LLR = 74; RLR = 74) consisting of compensated cirrhotic patients (100%) underwent non-anatomic resection of IWATE 1-2 class (90.5%) for a solitary tumor < 5cm in diameter (93.2%). In such patients, RLRs had shorter operative time (227 vs. 250min, p = 0.002), shorter Pringle's cumulative time (12 vs. 28min, p < 0.0001), and less blood loss (137 vs. 209cc, p = 0.006) vs. LLRs. Conversion rate was nihil (both groups). In RLRs compared to LLRs, R0 rate (93 vs. 96%, p>0.71) and major morbidity (4.1 vs. 5.4%, p>0.999) were similar, without post-operative mortality. Hospital stay was shorter in the robotic group (6.2 vs. 6.6, p = 0.0001). This study supports the non-inferiority of RLR over LLR. In compensated cirrhotic patients underwent resection of low-to-intermediate difficulty for a solitary nodule < 5cm, RLR was faster, with less blood loss despite the shorter hilar clamping, and required shorter hospitalization compared to LLR.

Short and long-term outcomes after minimally invasive liver resection for single small hepatocellular carcinoma: An analysis of 714 patients from the IGoMILS (Italian group of minimally invasive liver surgery) registry

BackgroundWidespread use of minimally invasive liver surgery (MILS) contributed to the reduction of surgical risk of liver resection for hepatocellular carcinoma (HCC). Aim of this study was to analyze outcomes of MILS for single ≤3 cm HCC. MethodsPatients who underwent MILS for single ≤3 cm HCC (November 2014 - December 2019) were identified from the Italian Group of Minimally Invasive Liver Surgery (IGoMILS) Registry. ResultsOf 714 patients included, 641 (93.0%) were Child-Pugh A; 65.7% were limited resections and 2.2% major resections, with a conversion rate of 5.2%. Ninety-day mortality rate was 0.3%. Overall morbidity rate was 22.4% (3.8% major complications). Mean postoperative stay was 5 days. Robotic resection showed longer operative time (p = 0.004) and a higher overall morbidity rate (p < 0.001), with similar major complications (p = 0.431). Child-Pugh B patients showed worse mortality (p = 0.017) and overall morbidity (p = 0.021), and longer postoperative stay (p = 0.005). Five-year overall survival was 79.5%; cirrhosis, satellite micronodules, and microvascular invasion were independently associated with survival. ConclusionsMILS for ≤3 cm HCC was associated with low morbidity and mortality rates, showing high safety, and supporting the increasing indications for surgical resection in these patients.

Validation of the Enhanced Recovery after Surgery (ERAS) society recommendations for liver surgery: a prospective, observational study.

Twenty-three recommendations were summarized by the Enhanced Recovery After Surgery (ERAS) society for liver surgery. The aim was to validate the protocol especially with regard to adherence and the impact on morbidity. Using the ERAS Interactive Audit System (EIAS), ERAS items were evaluated in patients undergoing liver resection. Over a period of 26 months, 304 patients were prospectively enrolled in an observational study (DRKS00017229). Of those, 51 patients (non-ERAS) were enrolled before and 253 patients (ERAS) after the implementation of the ERAS protocol. Perioperative adherence and complications were compared between the two groups. Overall adherence increased from 45.2% in the non-ERAS group to 62.7% in the ERAS group (P<0.001). This was associated with significant improvements in the preoperative and postoperative phase (P<0.001), rather than in the outpatient and intraoperative phase (both P>0.05). Overall complications decreased from 41.2% (n=21) in the non-ERAS group to 26.5% (n=67) in the ERAS group (P=0.0423), which was mainly due to the reduction of grade 1-2 complications from 17.6% (n=9) to 7.6% (n=19) (P=0.0322). As for patients undergoing open surgery, implementation of ERAS lead to a reduction of overall complications in patients scheduled for minimally invasive liver surgery (MILS) (P=0.036). Implementation of the ERAS protocol for liver surgery according to the ERAS guidelines of the ERAS Society reduced Clavien-Dindo grade 1-2 complications particularly in patients who underwent MILS. The ERAS guidelines are beneficial for the outcome, while adherence to the various items has not yet been satisfactorily defined.

Surgical Strategies for Combined Hepatocellular-Cholangiocarcinoma (cHCC-CC).

Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a tumor entity presenting features of hepatocellular and cholangiocellular epithelial differentiation. Due to the likeness between cHCC-CC, HCC and CC, accurate pretherapeutical diagnosis is challenging and advanced stages are prevalent. Radical oncological surgery is the only curative therapeutical option in patients with cHCC-CC. To reach this goal a profound understanding of this rare liver tumor is crucial. Factors such as clinicopathological characteristics, growth patterns and biological behavior are of central importance. To explore onco-surgical strategies and aspects for complete resection of cHCC-CC and to answer important key questions, an extensive review of the literature was conducted to answer the following questions: What are the best surgical options? Is there a significance for nonanatomical resections? Is there a prognostic value of concomitant lymphadenectomy? What about multimodal concepts in local advanced cHCC-CC? The role of minimally invasive liver surgery (MILS) including the role of robotic liver surgery for cHCC-CC will be discussed. While liver transplantation (LT) is standard for patients with unresectable HCC, the role of LT in cHCC-CC patients is still controversial. How can patients with high risk for early tumor recurrence be identified to avoid aggressive surgical treatment without clinical benefit? The comprehensive understanding of this challenging liver tumor will help to improve future treatment options for these patients.

Transatlantic registries for minimally invasive liver surgery: towards harmonization.

Several registries focus on patients undergoing minimally invasive liver surgery (MILS). This study compared transatlantic registries focusing on the variables collected and differences in baseline characteristics, indications, and treatment in patients undergoing MILS. Furthermore, key variables were identified. The five registries for liver surgery from North America (ACS-NSQIP), Italy, Norway, the Netherlands, and Europe were compared. A set of key variables were established by consensus expert opinion and compared between the registries. Anonymized data of all MILS procedures were collected (January 2014-December 2019). To summarize differences for all patient characteristics, treatment, and outcome, the relative and absolute largest differences (RLD, ALD) between the smallest and largest outcome per variable among the registries are presented. In total, 13,571 patients after MILS were included. Both 30- and 90-day mortality after MILS were below 1.1% in all registries. The largest differences in baseline characteristics were seen in ASA grade 3-4 (RLD 3.0, ALD 46.1%) and the presence of liver cirrhosis (RLD 6.4, ALD 21.2%). The largest difference in treatment was the use of neoadjuvant chemotherapy (RLD 4.3, ALD 20.6%). The number of variables collected per registry varied from 28 to 303. From the 46 key variables, 34 were missing in at least one of the registries. Despite considerable variation in baseline characteristics, indications, and treatment of patients undergoing MILS in the five transatlantic registries, overall mortality after MILS was consistently below 1.1%. The registries should be harmonized to facilitate future collaborative research on MILS for which the identified 46 key variables will be instrumental.

Robotic vs. laparoscopic resection for hepatocellular carcinoma

Minimally invasive liver surgery (MILS) has become increasingly popular over the last two decades, with hepatocellular carcinoma (HCC) representing a common indication. While data has shown the benefits of a laparoscopic vs. an open approach, robotic liver surgery is rapidly emerging. In this context, among the two minimal access approaches [robotic (RLR) vs. laparoscopic liver resection (LLR)], a differential benefit is still under investigation. While the advantages of RLR include increased dexterity, reduction of physiological tremors, and wrist articulation, it currently has no haptic feedback or specialized liver parenchymal transection devices and is associated with increased operative time and cost. However, RLR has proved to be a safe and effective approach for select patients with HCC. Some benefits of RLR include similar oncological outcomes to open or laparoscopic surgery, possibly reduced conversion rates, and an easier transition from open surgery to a minimally invasive approach. Moreover, while already today RLR can facilitate resection for HCC in hard-to-reach anatomic locations (e.g., transthoracic approach to posterior-superior liver), the future of robotics with the development of advanced image processing technologies, haptic feedback, liver-specific devices, lower cost, and more robot choices seems even more promising.

Minimally invasive ver-sus open liver resection for hepatocellular carcinoma in the elderly: international multicentre propensity score-matched study.

Hepatocellular carcinoma (HCC) is a disease with a high burden mainly affecting elderly patients. Most patients have underlying liver cirrhosis1,2. Elderly patients are increasingly seeking treatment for HCC in parallel with rising incidence and general life expectancy2–4. Resection is considered the most suitable curative option in elderly patients. Improvements in perioperative care and surgical techniques have mitigated the risks of resection, thereby expanding the pool of patients considered for resection1,5. One such improvement has been the adoption of minimally invasive liver surgery (MILS)6. For HCC, MILS has been associated with a shorter hospital stay, less blood loss, fewer transfusions, as well as lower mortality, and overall and liver-specific morbidity rates7–10. Concerns have been expressed, however, regarding its safety in elderly patients. The specific physiological stress endured during minimally invasive surgery might increase the morbidity and mortality risk in patients with limited reserve, but this hypothesis has not yet been supported by strong evidence11,12.

Selecting the Best Approach for the Treatment of Multiple Non-Metastatic Hepatocellular Carcinoma

According to the Barcelona Clinic Liver Cancer (BCLC) staging system, the optimal strategy for patients with multiple HCC within the Milan Criteria is liver transplantation (LT). However, LT cannot be offered to all the patients due to organ shortages and long waiting lists, as well as because of the advanced disease carrying a high risk of poor outcomes. For early stages, liver resection (LR) or thermal ablation (TA) can be proposed, while trans-arterial chemoembolization (TACE) still remains the treatment of choice for intermediate stages (BCLC-B). Asian guidelines and the National Comprehensive Cancer Network suggest LR for resectable multinodular HCCs, even beyond Milan criteria. In this scenario, a growing body of evidence shows better outcomes after surgical resection when compared with TACE. Trans-arterial radioembolization (TARE) and stereotaxic body radiation therapy (SBRT) can also play an important role in this setting. Furthermore, the role of minimally invasive liver surgery (MILS) specifically for patients with multiple HCC is still not clear. This review aims to summarize current knowledge about the best therapeutical strategy for multiple HCC while focusing on the role of minimally invasive surgery and on the most attractive future perspectives.

Current status of minimally invasive liver surgery for cancers

Hepatocellular carcinoma (HCC) patients have chronic liver disease with functional deterioration and multicentric oncogenicity. Liver surgeries for the patients should be planned on both oncological effects and sparing liver function. In colorectal patients with post-chemotherapy liver injury and multiple bilateral tumors, handling multiple tumors in a fragile/easy-to-bleed liver is an important issue. Liver surgery for biliary tract cancers is often performed as a resection of large-volume functioning liver with extensive lymphadenectomy and bile duct resection/reconstruction. Minimally invasive liver surgery (MILS) for HCC is applied with the advantages of laparoscopic for cases of cirrhosis or repeat resections. Small anatomical resections using the Glissonian, indocyanine green-guided, and hepatic vein-guided approaches are under discussion. In many cases of colorectal liver metastases, MILS is applied combined with chemotherapy owing to its advantage of better hemostasis. Two-stage hepatectomy and indocyanine green-guided tumor identification for multiple bilateral tumors are under discussion. In the case of biliary tract cancers, MILS with extensive lymphadenectomy and bile duct resection/reconstruction are developing. A robot-assisted procedure for dissection of major vessels and handling fragile livers may have advantages, and well-simulated robot-assisted procedure may decrease the difficulty for biliary tract cancers.

Indications, trends, and perioperative outcomes of minimally invasive and open liver surgery in non-obese and obese patients: An international multicentre propensity score matched retrospective cohort study of 9963 patients

BackgroundDespite the worldwide increase of both obesity and the use of minimally invasive liver surgery (MILS), evidence regarding the safety and eventual benefits of MILS in obese patients is scarce. The aim of this study was therefore to compare the outcomes of non-obese and obese patients (BMI 18.5–29.9 and BMI≥30, respectively) undergoing MILS and OLS, and to assess trends in MILS use among obese patients. MethodsIn this retrospective cohort study, patients operated at 20 hospitals in eight countries (2009–2019) were included and the characteristics and outcomes of non-obese and obese patients were compared. Thereafter, the outcomes of MILS and OLS were compared in both groups after propensity-score matching (PSM). Changes in the adoption of MILS during the study period were investigated. ResultsOverall, 9963 patients were included (MILS: n = 4687; OLS: n = 5276). Compared to non-obese patients (n = 7986), obese patients(n = 1977) were more often comorbid, less often received preoperative chemotherapy or had a history of previous hepatectomy, had longer operation durations and more intraoperative blood loss (IOBL), paralleling significantly higher rates of wound- and respiratory-related complications. After PSM, MILS, compared to OLS, was associated, among both non-obese and obese patients, with less IOBL (200 ml vs 320 ml, 200 ml vs 400 ml, respectively), lower rates of transfusions (6.6% vs 12.8%, 4.7% vs 14.7%), complications (26.1% vs 35%, 24.9% vs 34%), bile leaks(4% vs 7%, 1.8% vs 4.9%), liver failure (0.7% vs 2.3%, 0.2% vs 2.1%), and a shorter length of stay(5 vs 7 and 4 vs 7 days). A cautious implementation of MILS over time in obese patients (42.1%–53%, p < .001) was paralleled by stable severe morbidity (p = .433) and mortality (p = .423) rates, despite an accompanying gradual increase in surgical complexity. ConclusionsMILS is increasingly adopted and associated with perioperative benefits in both non-obese and obese patients.

Robotic Left Hepatectomy using Indocyanine Green Fluorescence Imaging for an Intrahepatic Complex Biliary Cyst

Biliary cysts (BC) are rare congenital dilatations of intra- and extrahepatic parts of the biliary tract and bear a significant risk of carcinogenesis. Surgery is the cornerstone treatment for patients with BC. While total BC excision and Roux-Y hepaticojejunostomy is the treatment method of the choice in patients with extrahepatic BC (i.e., Todani I-IV), patients with intrahepatic BC (i.e., Todani V) benefit the most from a surgical liver resection. In recent years, minimally invasive liver surgery (MILS) including robotic MILS has gained more acceptance as a feasible, safe, and effective procedure for the treatment of both benign and malignant indications. Robotic major MILS is still considered technically demanding and a detailed description of the technical approach during robotic major MILS has only been limitedly discussed in the literature. The current article describes the main steps for a robotic left hepatectomy in a patient with a large BC Todani Type V. The patient is in French position with 5 trocars placed (4 robotic, 1 laparoscopic assistant). After mobilizing the left hemiliver, the left and right hepatic artery are dissected carefully followed by a cholecystectomy. Intraoperative ultrasound is performed to confirm localization and margins of the BC. The Left hepatic artery and left portal vein are isolated, clipped, and divided. Indocyanine green (ICG) fluorescence imaging is used regularly during the entire procedure to visualize and confirm biliary tract anatomy and the BC. Parenchymal transection is performed with robotic cautery hook for the superficial part and robotic cautery spatula, bipolar cautery, and vessel sealer for the deeper parenchyma. The postoperative course was uncomplicated. A robotic left hepatectomy is technically demanding, yet a feasible and safe procedure. ICG-fluorescence imaging aids in delineating the BC and bile duct anatomy. Further, comparative studies are needed to confirm clinical benefits of robotic MILS for benign and malignant indications.

Robotic Left Hepatectomy using Indocyanine Green Fluorescence Imaging for an Intrahepatic Complex Biliary Cyst.

Biliary cysts (BC) are rare congenital dilatations of intra- and extrahepatic parts of the biliary tract and bear a significant risk of carcinogenesis. Surgery is the cornerstone treatment for patients with BC. While total BC excision and Roux-Y hepaticojejunostomy is the treatment method of the choice in patients with extrahepatic BC (i.e., Todani I-IV), patients with intrahepatic BC (i.e., Todani V) benefit the most from a surgical liver resection. In recent years, minimally invasive liver surgery (MILS) including robotic MILS has gained more acceptance as a feasible, safe, and effective procedure for the treatment of both benign and malignant indications. Robotic major MILS is still considered technically demanding and a detailed description of the technical approach during robotic major MILS has only been limitedly discussed in the literature. The current article describes the main steps for a robotic left hepatectomy in a patient with a large BC Todani Type V. The patient is in French position with 5 trocars placed (4 robotic, 1 laparoscopic assistant). After mobilizing the left hemiliver, the left and right hepatic artery are dissected carefully followed by a cholecystectomy. Intraoperative ultrasound is performed to confirm localization and margins of the BC. The Left hepatic artery and left portal vein are isolated, clipped, and divided. Indocyanine green (ICG) fluorescence imaging is used regularly during the entire procedure to visualize and confirm biliary tract anatomy and the BC. Parenchymal transection is performed with robotic cautery hook for the superficial part and robotic cautery spatula, bipolar cautery, and vessel sealer for the deeper parenchyma. The postoperative course was uncomplicated. A robotic left hepatectomy is technically demanding, yet a feasible and safe procedure. ICG-fluorescence imaging aids in delineating the BC and bile duct anatomy. Further, comparative studies are needed to confirm clinical benefits of robotic MILS for benign and malignant indications.

Leaping the Boundaries in Laparoscopic Liver Surgery for Hepatocellular Carcinoma.

The minimally invasive approach for hepatocellular carcinoma (HCC) had a slower diffusion compared to other surgical fields, mainly due to inherent peculiarities regarding the risks of uncontrollable bleeding, oncological inadequacy, and the need for both laparoscopic and liver major skills. Recently, laparoscopic liver resection (LLR) has been associated with an improved postoperative course, including reduced postoperative decompensation, intraoperative blood losses, length of hospitalization, and unaltered oncological outcomes, leading to its adoption within international guidelines. However, LLR for HCC still faces several limitations, mainly linked to the impaired function of underlying parenchyma, tumor size and numbers, and difficult tumor position. The aim of this review is to highlight the state of the art and future perspectives of LLR for HCC, focusing on key points for overcoming currents limitations and pushing the boundaries in minimally invasive liver surgery (MILS).

Pan-European survey on the implementation of robotic and laparoscopic minimally invasive liver surgery.

Laparoscopic and robotic minimally invasive liver surgery (MILS) is gaining popularity. Recent data and views on the implementation of laparoscopic and robotic MILS throughout Europe are lacking. An anonymous survey consisting of 46 questions was sent to all members of the European-African Hepato-Pancreato-Biliary Association. The survey was completed by 120 surgeons from 103 centers in 24 countries. Median annual center volume of liver resection was 100 [IQR 50-140]. The median annual volume of MILS per center was 30 [IQR 16-40]. For minor resections, laparoscopic MILS was used by 80 (67%) surgeons and robotic MILS by 35 (29%) surgeons. For major resections, laparoscopic MILS was used by 74 (62%) surgeons and robotic MILS by 33 (28%) surgeons. The majority of the surgeons stated that minimum annual volume of MILS per center should be around 21-30 procedures/year. Of the surgeons performing robotic surgery, 28 (70%) felt they missed specific equipment, such as a robotic-CUSA. Seventy (66%) surgeons provided a formal MILS training to residents and fellows. In 5 years' time, 106 (88%) surgeons felt that MILS would have superior value as compared to open liver surgery. In the participating European liver centers, MILS comprised about one third of all liver resections and is expected to increase further. Laparoscopic MILS is still twice as common as robotic MILS. Development of specific instruments for robotic liver parenchymal transection might further increase its adoption.

Complexity-Adjusted Learning Curves for Robotic and Laparoscopic Liver Resection: A Word of Caution.

Minimally invasive liver surgery (MILS) has a high variance in the type of resection and complexity, which has been underestimated in learning curve studies in the past. The aim of this work was to evaluate complexity-adjusted learning curves over time for laparoscopic liver resection (LLR) and robotic liver resection (RLR). Cumulative sum analysis (CUSUM) and complexity adjustment were performed using the Iwate score for LLR and RLR (n = 647). Lowest point of smoothed data was used to capture the cutoff of the increase in complexity. Data were collected retrospectively at the Department of Surgery of the Charité-Universitätsmedizin Berlin. A total of 132 RLR and 514 LLR were performed. According to the complexity-adjusted CUSUM analysis, the initial learning phase was reached after 117 for LLR and 93 procedures for RLR, respectively. With increasing experience, the rate of (extended) right hemihepatectomy multiplied from 8.4% to 18.9% for LLR (P = 0.031) and from 21.6% to 58.3% for RLR (P < 0.001). Complication rates remained comparable between both episodes for LLR and RLR (T1 vs T2, P > 0.05). The complexity-adjusted CUSUM analysis demonstrated for blood transfusion, conversion, and operative time an increase during the learning phase (T1), while a steady state was reached in the following (T2). The learning phase for MILS after adjusting for complexity is about 4 times longer than assumed in previous studies, which should urge caution.