Single Port Robotic Liver Resection: Metastasectomy for Recurrent Fibrolamellar Hepatocellular Carcinoma.

BACKGROUND: Robotic surgery has emerged as a promising approach for managing complex hepatic malignancies. This report presents a case of a single-port robotic liver resection for a patient with recurrent hepatocellular carcinoma (HCC) and metastases, focusing on the surgical technique and outcomes. METHOD: An 18-year-old female with a history of left hepatectomy for fibrolamellar HCC underwent robotic liver resection using the Da Vinci SP Surgical System. The procedure entailed excising a 30 mm tumor in liver segment 4 (Sg4) along with peritoneal metastases in the superior pole of the spleen and cardiophrenic lymph node metastasis. Surgical techniques comprised adhesiolysis, resection of the peritoneal nodule, Sg4 partial liver resection, and excision of the cardiophrenic lymph node. RESULTS: The operative time was 310 min, with a blood loss of 37 mL. The patient experienced an uneventful postoperative course and was discharged home after 8 days. Partial liver resection of Sg4 revealed a moderately differentiated HCC with negative resection margins. Additionally, excision of peritoneal metastases in the superior pole of the spleen and cardiophrenic lymph nodes, consistent with metastasis, was performed. Notably, the Da Vinci SP system's relocation function proved useful in this case, particularly in slender patients with multiple distant metastases. CONCLUSION: This case underscores the importance of technological advancements in robotic surgery. The Da Vinci SP system, with its advantageous features, shows promise in challenging clinical scenarios. Its ability to facilitate precise navigation and manipulation within the patient's restricted abdominal cavity contributed to the observed successful outcome.

Harmonizing Definitions and Perspectives in Extreme Liver Surgery: A Delphi Experts Consensus.

OBJECTIVE: To propose to our community a common language about extreme liver surgery. BACKGROUND: The lack of a clear definition of extreme liver surgery prevents convincing comparisons of results among centers. METHODS: We used a two-round Delphi methodology to quantify consensus among liver surgery experts. For inclusion in the final recommendations, we established a consensus when the positive responses (agree and totally agree) exceeded 70%. The study steering group summarized and reported the recommendations. In general, a five-point Likert scale with a neutral central value was used, and in a few cases multiple choices. Results are displayed as numbers and percentages. RESULTS: A two-round Delphi study was completed by 38 expert surgeons in complex hepatobiliary surgery. The surgeon´s median age was 58 years old (52-63) and the median years of experience was 25 years (20-31). For the proposed definitions of total vascular occlusion, hepatic flow occlusion and inferior vein occlusion, the degree of agreement was 97%, 81% and 84%, respectively. In situ approach (64%) was the preferred, followed by ante situ (22%) and ex situ (14%). Autologous or cadaveric graft for hepatic artery or hepatic vein repair were the most recommended (89%). The use of veno-venous bypass or portocaval shunt revealed the divergence depending on the case. Overall, 75% of the experts agreed with the proposed definition for extreme liver surgery. CONCLUSION: Obtaining a consensus on the definition of extreme liver surgery is essential to guarantee the correct management of patients with highly complex hepatobiliary oncological disease. The management of candidates for extreme liver surgery involves comprehensive care ranging from adequate patient selection to the appropriate surgical strategy.

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.

Global Outcomes Benchmarks in Laparoscopic Liver Surgery for Segments 7 and 8: International Multicenter Analysis.

BACKGROUND: In recent years, there has been growing interest in laparoscopic liver resection (LLR) and the audit of the results of surgical procedures. The aim of this study was to define reference values for LLR in segments 7 and 8. METHODS: Data on LLR in segments 7 and 8 between January 2000 and December 2020 were collected from 19 expert centers. Reference cases were defined as no prior hepatectomy, ASA <3, body mass index <35 kg/m2, no chronic kidney disease, no cirrhosis and portal hypertension, no chronic obstructive pulmonary disease (FEV1<80%), and no cardiac disease. Reference values were obtained from the 75th percentile of the medians of all reference centers. RESULTS: Of 585 patients, 461 (78.8%) met the reference criteria. The overall complication rate was 27.5% (6% were Clavien-Dindo≥3a) with a mean CCI of 7.5 ± 16.5. At 90-day follow-up, the references values for overall complications were 31%, Clavien≥3a 7.4%, conversion 4.4%, hospital stay < 6 days, and readmission rate < 8.33%, respectively. Eastern centers patients categorized as low risk had a lower rate of overall complications (20.9% vs 31.2%, p=0.01) with similar Clavien-Dindo≥3a (5.5% and 4.8%, p=0.83) compared to Western centers, respectively. CONCLUSION: This study shows the need to establish standards for the postoperative outcomes in LLR based on the complexity of the resection and the location of the lesions.

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.

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.

Safety and short-term outcomes of robotic-assisted transabdominal preperitoneal repair for inguinal hernia in pioneering hospitals in Japan: A nationwide retrospective cohort study.

INTRODUCTION: We aimed to evaluate the safety and short-term outcomes of robotic-assisted transabdominal preperitoneal repair for inguinal hernia in 12 pioneering hospitals in Japan. METHODS: Clinical data of patients who underwent robotic-assisted transabdominal preperitoneal repair between September 1, 2016, and December 31, 2021 were collected. Primary outcome measures were intra-operative adverse events and post-operative complications, whereas secondary outcomes were surgical outcomes, including chronic pain, recurrence, and learning curve. RESULTS: In total, 307 patients were included. One case of inferior epigastric arterial injury was reported; no cases of bowel or bladder injury were reported. Thirty-five seromas were observed, including four (1.3%) cases that required aspiration. The median operative time of a unilateral case was 108 minutes (interquartile range: 89.8-125.5), and post-operative pain was rated 1 (interquartile range: 0-2) on the numerical rating scale. In complicated cases, such as recurrent inguinal hernias and robotic-assisted radical prostatectomy-associated hernias, dissection and suture were safely achieved, and no complications were observed, except for non-symptomatic seroma. All patients underwent robotic procedures, and there was no chronic post-operative inguinal pain, although one case of hernia recurrence was reported. Regarding the learning curve, plateau performance was achieved after 7-10 cases in terms of operative time (P < .001). CONCLUSION: Robotic-assisted transabdominal preperitoneal repair can be safely introduced in Japan. Regardless of the involvement of many surgeons, the mastery of robotic techniques was achieved relatively quickly. The advantage of robotic technology such as wristed instruments may expand the application of minimally invasive hernia repair for complicated cases.

Laparoscopically Limited Anatomic Liver Resections: A Single-Center Analysis for Oncologic Outcomes of the Conceptual Procedure.

BACKGROUND: Limited anatomic resections (LARs), such as segmentectomies, performed using a fully laparoscopic approach, have gained popularity for liver malignancies. However, the oncologic efficacy of laparoscopic LARs (Lap-LARs) needs further investigation. This cohort study evaluated the oncologic outcomes of Lap-LAR for hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM). METHODS: At a Japanese referral center, 112 patients underwent Lap-LAR using the Glissonean approach and indocyanine green (ICG) fluorescence navigation. Recurrence-free survival (RFS), overall survival (OS), time to interventional failure (TIF), and time to surgical failure (TSF) were assessed. RESULTS: Among the 112 patients (median age, 74 years [range, 66-80 years]; 80 men [71.4 %]), Lap-LAR showed promising results. The median operative time was 348 min (range, 280-460 min), and the median blood loss was 190 mL (range, 95.5-452.0 mL). The median error between the estimated and actual liver volumes was 2 % (1.2-4.8 %). Complications greater than Clavien-Dindo 3a were observed in 11.6 % of the patients. The 5-year RFS, OS, and TIF rates for HCC were 45.1 % ± 7.9 %, 73.1 % ± 6.7 %, and 74.2 % ± 6 .6 %, respectively. The 5-year RFS, OS, and TSF rates for CRLM were 36.8 % ± 8.7 %, 60.1 % ± 13.3 %, and 63.6 % ± 10.4 %, respectively. CONCLUSIONS: Lap-LAR showed favorable oncologic outcomes for HCC and CRLM. Its precise technique makes it a promising therapeutic option for liver malignancies. Further comparisons with conventional approaches are warranted.

Combining preoperative C-reactive protein values with the Tokyo Guidelines 2018 grading criteria can enhance the prediction of surgical difficulty in early laparoscopic cholecystectomy for acute cholecystitis.

BACKGROUND: Early laparoscopic cholecystectomy (ELC) is the standard treatment for acute cholecystitis (AC). However, predicting the difficulty of this procedure remains challenging. The present study aimed to develop an improved prediction model for surgical difficulty during ELC, surpassing the current Tokyo Guidelines 2018 (TG18) grading system. METHODS: We analyzed data from 201 consecutive patients who underwent ELC for AC between 2019 and 2021. Surgical difficulty was defined as the failure to achieve the critical view of safety (non-CVS). We developed a scoring system by conducting multivariate analysis on demographics, symptoms, laboratory data, and radiographic findings. The predictive accuracy of our scoring system was compared to that of the TG18 grading system (Grade I vs. Grade II/III). RESULTS: Through multivariate logistic regression analysis, a novel scoring system was formulated. This system incorporated preoperative C-reactive protein (CRP) values (≥5: 1 pt, ≥10: 2 pts, ≥15: 3 pts) and TG18 grading score (duration >72 h: 1 pt, image criteria for Grade II AC: 1 pt). Our model, a cutoff score of ≥3, exhibited a significantly elevated area under the curve (AUC) of 0.721 compared to the TG18 grading system alone (AUC 0.609) (p = 0.001). CONCLUSION: Combining preoperative CRP values with TG18 grading criteria can enhance the accuracy of predicting intraoperative difficulty in ELC for AC.

International experts consensus guidelines on robotic liver resection in 2023.

The robotic liver resection (RLR) has been increasingly applied in recent years and its benefits shown in some aspects owing to the technical advancement of robotic surgical system, however, controversies still exist. Based on the foundation of the previous consensus statement, this new consensus document aimed to update clinical recommendations and provide guidance to improve the outcomes of RLR clinical practice. The guideline steering group and guideline expert group were formed by 29 international experts of liver surgery and evidence-based medicine (EBM). Relevant literature was reviewed and analyzed by the evidence evaluation group. According to the WHO Handbook for Guideline Development, the Guidance Principles of Development and Amendment of the Guidelines for Clinical Diagnosis and Treatment in China 2022, a total of 14 recommendations were generated. Among them were 8 recommendations formulated by the GRADE method, and the remaining 6 recommendations were formulated based on literature review and experts' opinion due to insufficient EBM results. This international experts consensus guideline offered guidance for the safe and effective clinical practice and the research direction of RLR in future.

Comparing the accuracy of positive and negative indocyanine green staining in guiding laparoscopic anatomical liver resection: protocol for a randomised controlled trial.

INTRODUCTION: Knowledge of the clinical liver anatomy has evolved with advanced imaging modalities and laparoscopic surgery. Therefore, precise anatomical resection knowledge has become the standard treatment for primary and secondary liver cancer. Segmentectomy, a parenchymal-preserving approach, is regarded as an option for anatomical resections in patients with impaired liver. Indocyanine green (ICG) staining is a promising method for understanding the anatomical borders of the liver segments. There are two methods of ICG staining (positive and negative), and the superiority of either approach has not been determined to date. METHODS AND ANALYSIS: This is a prospective randomised controlled superiority clinical trial performed in a single centre tertiary hospital in Japan. A comparison between the accuracy of positive and negative ICG staining in guiding laparoscopic anatomical liver resection is planned in this study. Possible candidates are patients with liver malignant tumours in whom laparoscopic monosegmentectomy or subsegmentectomy is planned. Fifty patients will be prospectively allocated into the following two groups: group A, ICG-negative staining group, and group B, ICG-positive staining group. The optimal dose of ICG for positive staining will be determined during the preparation phase. To assess the ability of the ICG fluorescence guidance in anatomical resection, the primary endpoint is the success rate of ICG staining, which consists of a SOS based on three components: superficial demarcation in the liver surface, visualisation of the parenchymal borders and consistency with the preoperative three-dimensional simulation. The secondary endpoints are the evaluation of short-term surgical outcomes and recurrence-free survival. ETHICS AND DISSEMINATION: The study was approved by Ageo Central General Hospital Clinical Research Ethical Committee (No: 1044) and it carried out following the Declaration of Helsinki (2013 revision). Informed consent will be taken from the patients before participating. The findings will be disseminated through peer-reviewed publications, scientific meetings and conferences. TRIAL REGISTRATION NUMBER: UMIN000049815.

Time required for indocyanine green fluorescence emission for evaluating bowel perfusion in left-sided colon and rectal cancer surgery.

BACKGROUND: Indocyanine green fluorescence imaging (ICG-FI) has been reported to be useful in reducing the incidence of anastomotic leakage (AL) in colectomy. This study aimed to investigate the correlation between the required time for ICG fluorescence emission and AL in left-sided colon and rectal cancer surgery using the double-stapling technique (DST) anastomosis. METHODS: This retrospective study included 217 patients with colorectal cancer who underwent left-sided colon and rectal surgery using ICG-FI-based perfusion assessment at our department between November 2018 and July 2022. We recorded the time required to achieve maximum fluorescence emission after ICG systemic injection and assessed its correlation with the occurrence of AL. RESULTS: Among 217 patients, AL occurred in 21 patients (9.7%). The median time from ICG administration to maximum fluorescence emission was 32 s (range 25-58 s) in the AL group and 28 s (range 10-45 s) in the non-AL group (p < 0.001). The cut-off value for the presence of AL obtained from the ROC curve was 31 s. In 58 patients with a required time for ICG fluorescence of 31 s or longer, the following risk factors for AL were identified: low preoperative albumin [3.4 mg/dl (range 2.6-4.4) vs. 3.9 mg/dl (range 2.6-4.9), p = 0.016], absence of preoperative mechanical bowel preparation (53.8% vs. 91.1%, p = 0.005), obstructive tumor (61.5% vs. 17.8%, p = 0.004), and larger tumor diameter [65 mm (range 40-90) vs. 35 mm (range 4.0-100), p < 0.001]. CONCLUSION: The time required for ICG fluorescence emission was associated with AL.

Robotic versus laparoscopic liver resection for huge (≥10 cm) liver tumors: an international multicenter propensity-score matched cohort study of 799 cases.

Background: The use of laparoscopic (LLR) and robotic liver resections (RLR) has been safely performed in many institutions for liver tumours. A large scale international multicenter study would provide stronger evidence and insight into application of these techniques for huge liver tumours ≥10 cm. Methods: This was a retrospective review of 971 patients who underwent LLR and RLR for huge (≥10 cm) tumors at 42 international centers between 2002-2020. Results: One hundred RLR and 699 LLR which met study criteria were included. The comparison between the 2 approaches for patients with huge tumors were performed using 1:3 propensity-score matching (PSM) (73 vs. 219). Before PSM, LLR was associated with significantly increased frequency of previous abdominal surgery, malignant pathology, liver cirrhosis and increased median blood. After PSM, RLR and LLR was associated with no significant difference in key perioperative outcomes including media operation time (242 vs. 290 min, P=0.286), transfusion rate rate (19.2% vs. 16.9%, P=0.652), median blood loss (200 vs. 300 mL, P=0.694), open conversion rate (8.2% vs. 11.0%, P=0.519), morbidity (28.8% vs. 21.9%, P=0.221), major morbidity (4.1% vs. 9.6%, P=0.152), mortality and postoperative length of stay (6 vs. 6 days, P=0.435). Conclusions: RLR and LLR can be performed safely for selected patients with huge liver tumours with excellent outcomes. There was no significant difference in perioperative outcomes after RLR or LLR.

Latest Findings on Minimally Invasive Anatomical Liver Resection.

Minimally invasive liver resection (MILR) is being widely utilized owing to recent advancements in laparoscopic and robot-assisted surgery. There are two main types of liver resection: anatomical (minimally invasive anatomical liver resection (MIALR)) and nonanatomical. MIALR is defined as a minimally invasive liver resection along the respective portal territory. Optimization of the safety and precision of MIALR is the next challenge for hepatobiliary surgeons, and intraoperative indocyanine green (ICG) staining is considered to be of considerable importance in this field. In this article, we present the latest findings on MIALR and laparoscopic anatomical liver resection using ICG at our hospital.

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.

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.

Early laparoscopic cholecystectomy for acute cholecystitis following the Tokyo Guidelines 2018: a prospective single-center study of 201 consecutive cases.

BACKGROUND: Early laparoscopic cholecystectomy (ELC) for acute cholecystitis (AC) poses multiple challenges. The Tokyo Guidelines 2018 (TG18) eliminated the time limit (< 72 h) and expanded the surgical indication to severe AC. This study aimed to evaluate the clinical outcomes of ELC for AC following the TG18 in a single high-volume center. METHODS: From 2019 to 2021, we managed all AC patients with a TG18 flowchart and prospectively enrolled those who underwent ELC within 7 days of symptom onset. The primary outcome was overall morbidity, with a comparison between mild (Grade I) and moderate/severe (Grade II/III) AC. RESULTS: During the study period, 201 patients underwent ELC was for Grade I (56.2%), II (40.3%), and III (3.5%) ACs. Mean age was 69 ± 15.2 years and time to surgery from symptom onset was 0 (12.9%), 1-3 (66.7%), and 4-7 days (20.4%). Mean operative time and blood loss were 118.9 ± 42.7 min and 57.8 ± 99.4 mL, respectively. The critical view of safety (CVS) was achieved in 76.1% of patients, and bailout procedures were performed in 21.4%. There were no open conversions or bile duct injuries. Major morbidities (Clavien-Dindo classification ≥ IIIa) were observed in 5.5% of cases and mortality in 0.5%. Comparing Grades II/III to Grade I, operative time was longer (112.3 vs. 127.3 min, p = 0.014), blood loss was higher (40.3 vs. 80.1 mL, p = 0.005), the CVS rate was lower (83.2 vs. 67.0%, p = 0.012), and the major morbidity rate was higher (1.8 vs. 10.2%, p = 0.012). In the subgroup analysis of Grade II/III, there were no significant differences in major morbidities (p = 0.288) between the two groups (0-3 vs. 4-7 days). CONCLUSION: ELC for AC following TG18 is feasible with low morbidity rates. However, ELC for Grade II/III ACs remains challenging, and surgeons must carefully assess intraoperative difficulties and surgical risks before proceeding.