The impact of obesity on short-term outcomes after the laparoscopic liver resection: a single-institution experience.

Introduction: Obesity is a major public health problem and a well-known cause of multiple comorbidities. With the increasing application of minimally invasive surgery for benign and malignant liver lesions, the results of laparoscopic liver resection (LLR) in obese patients are of great interest. Aim: To evaluate the short-term operative outcomes after LLR in obese patients and compare them to patients with normal weight and overweight. Material and methods: All 235 consecutive patients undergoing LLR from 2008 to 2023 were retrospectively analysed. Patients were categorized into 3 groups based on their body mass index (BMI): normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), and obese (≥ 30 kg/m2). The groups were then compared regarding preoperative data and intra- and postoperative outcomes. Results: Despite higher ASA score and associated comorbidities in the obese group, there were no significant differences in intraoperative complication (blood loss, damage to surrounding structures, conversion rate) between BMI groups (20.8% vs. 16.8% vs. 22.7%, p = 0.619). There were no significant differences in overall morbidity (34.7% vs. 27.7% vs. 29.5%, p = 0.582), as well as major morbidity (15.9% vs. 11.8% vs. 11.4%, p = 0.784) or mortality rates (1.4% vs. 1.7% vs. 0.0%, p = 1.000). Univariate logistic regression did not show BMI or obesity as a predictive variable for intraoperative complication. Conclusions: Obesity is not a significant, strong risk factor for worse short-term outcomes, and LLR may be considered also in patients with overweight and obesity.

Ranking as a Procedure for Selecting a Replacement Variable in the Score Predicting the Survival of Patients Treated with Curative Intent for Colorectal Liver Metastases.

Background and Objectives: The issue of a missing variable precludes the external validation of many prognostic models. For example, the Liverpool score predicts the survival of patients undergoing surgical therapy for colorectal liver metastases, but it includes the neutrophil-lymphocyte ratio, which cannot be measured retrospectively. Materials and Methods: We aimed to find the most appropriate replacement for the neutrophil-lymphocyte ratio. Survival analysis was performed on data representing 632 liver resections for colorectal liver metastases from 2000 to 2020. Variables associated with the Liverpool score, C-reactive protein, albumins, and fibrinogen were ranked. The rankings were performed in four ways: The first two were based on the Kaplan-Meier method (log-rank statistics and the definite integral IS between two survival curves). The next method of ranking was based on univariate and multivariate Cox regression analyses. Results: The ranks were as follows: the radicality of liver resection (rank 1), lymph node infiltration of primary colorectal cancer (rank 2), elevated C-reactive protein (rank 3), the American Society of Anesthesiologists Classification grade (rank 4), the right-sidedness of primary colorectal cancer (rank 5), the multiplicity of colorectal liver metastases (rank 6), the size of colorectal liver metastases (rank 7), albumins (rank 8), and fibrinogen (rank 9). Conclusions: The ranking methodologies resulted in almost the same ranking order of the variables. Elevated C-reactive protein was ranked highly and can be considered a relevant replacement for the neutrophil-lymphocyte ratio in the Liverpool score. These methods are suitable for ranking variables in similar models for medical research.

Two-stage hepatectomy in resection of colorectal liver metastases - a single-institution experience with case-control matching and review of the literature.

BACKGROUND: Two-stage hepatectomy (TSH) has been proposed for patients with bilateral liver tumours who have a high risk of posthepatectomy liver failure after one-stage hepatectomy (OSH). This study aimed to determine the outcomes of TSH for extensive bilateral colorectal liver metastases. PATIENTS AND METHODS: A retrospective review of a prospectively maintained database of liver resections for colorectal liver metastases was conducted. The TSH group was compared to the OSH group in terms of perioperative outcomes and survival. Case-control matching was performed. RESULTS: A total of 632 consecutive liver resections for colorectal liver metastases were performed between 2000 and 2020. The study group (TSH group) consisted of 15 patients who completed TSH. The control group included 151 patients who underwent OSH. The case-control matching-OSH group consisted of 14 patients. The major morbidity and 90-day mortality rates were 40% and 13.3% in the TSH group, 20.5% and 4.6% in the OSH group and 28.6% and 7.1% in the case-control matching-OSH group, respectively. The recurrence-free survival, median overall survival, and 3- and 5-year survival rates were 5 months, 21 months, 33% and 13% in the TSH group; 11 months, 35 months, 49% and 27% in the OSH group; and 8 months, 23 months, 36% and 21%, respectively, in the case-control matching-OSH group, respectively. CONCLUSIONS: TSH used to be a favourable therapeutic choice in a select population of patients. Now, OSH should be preferred whenever feasible because it has lower morbidity and equivalent oncological outcomes to those of completed TSH.

The learning curve of laparoscopic liver resection utilising a difficulty score.

BACKGROUND: This study aimed to quantitatively evaluate the learning curve of laparoscopic liver resection (LLR) of a single surgeon. PATIENTS AND METHODS: A retrospective review of a prospectively maintained database of liver resections was conducted. 171 patients undergoing pure LLRs between April 2008 and April 2021 were analysed. The Halls difficulty score (HDS) for theoretical predictions of intraoperative complications (IOC) during LLR was applied. IOC was defined as blood loss over 775 mL, unintentional damage to the surrounding structures, and conversion to an open approach. Theoretical association between HDS and the predicted probability of IOC was utilised to objectify the shape of the learning curve. RESULTS: The obtained learning curve has resulted from thirteen years of surgical effort of a single surgeon. It consists of an absolute and a relative part in the mathematical description of the additive function described by the logarithmic function (absolute complexity) and fifth-degree regression curve (relative complexity). The obtained learning curve determines the functional dependency of the learning outcome versus time and indicates several local extreme values (peaks and valleys) in the learning process until proficiency is achieved. CONCLUSIONS: This learning curve indicates an ongoing learning process for LLR. The proposed mathematical model can be applied for any surgical procedure with an existing difficulty score and a known theoretically predicted association between the difficulty score and given outcome (for example, IOC).

Evaluation of the Iwate Model for Predicting the Difficulty of Laparoscopic Liver Resection: Does Tumor Size Matter?

BACKGROUND: This study aimed to externally validate the Iwate scoring model and its prognostic value for predicting the risks of intra- and postoperative complications of laparoscopic liver resection. METHODS: Consecutive patients who underwent pure laparoscopic liver resection between 2008 and 2019 at a single tertiary center were included. The Iwate scores were calculated according to the original proposition (four difficulty levels based on six indices). Intra- and postoperative complications were compared across difficulty levels. Fitting the obtained data to the cumulative density function of the Weibull distribution and a linear function provided the mean risk curves for intra- and postoperative complications, respectively. RESULTS: The difficulty levels of 142 laparoscopic liver resections were scored as low, intermediate, advanced, and expert level in 41 (28.9%), 53 (37.3%), 32 (22.5%), and 16 (11.3%) patients, respectively. Intraoperative complications were detected in 26 (18.3%) patients and its rates (2.4%, 7.5%, 34.3%, and 62.5%) increased gradually with statistically significant values among difficulty levels (P Ë‚ 0.001). Major postoperative complications occurred in 21 (14.8%) patients and its rates (4.8%, 5.6%, 28.1%, 43.7%; P Ë‚ 0.001) showed the same trend as for intraoperative complications. Then, the mean risk curves of both complications were obtained. Due to outliers, a new threshold for a tumor size index was proposed at 38 mm. The repeated analysis showed improved results. CONCLUSIONS: The Iwate scoring model predicts the probability of complications across difficulty levels. Our proposed tumor size threshold (38 mm) improves the quality of the prediction. The model is upgraded by a probability of complications for every difficulty score.

The external validation of a difficulty scoring system for predicting the risk of intraoperative complications during laparoscopic liver resection.

BACKGROUND: This study aimed to externally validate and upgrade the recent difficulty scoring system (DSS) proposed by Halls et al. to predict intraoperative complications (IOC) during laparoscopic liver resection (LLR). METHODS: The DSS was validated in a cohort of 128 consecutive patients undergoing pure LLRs between 2008 and 2019 at a single tertiary referral center. The validated DSS includes four difficulty levels based on five risk factors (neoadjuvant chemotherapy, previous open liver resection, lesion type, lesion size and classification of resection). As established by the validated DSS, IOC was defined as excessive blood loss (> 775 mL), conversion to an open approach and unintentional damage to surrounding structures. Additionally, intra- and postoperative outcomes were compared according to the difficulty levels with usual statistic methods. The same five risk factors were used for validation done by linear and advanced nonlinear (artificial neural network) models. The study was supported by mathematical computations to obtain a mean risk curve predicting the probability of IOC for every difficulty score. RESULTS: The difficulty level of LLR was rated as low, moderate, high and extremely high in 36 (28.1%), 63 (49.2%), 27 (21.1%) and 2 (1.6%) patients, respectively. IOC was present in 23 (17.9%) patients. Blood loss of >775 mL occurred in 8 (6.2%) patients. Conversion to open approach was required in 18 (14.0%) patients. No patients suffered from unintentional damage to surrounding structures. Rates of IOC (0, 9.5, 55.5 and 100%) increased gradually with statistically significant value among difficulty levels (P < 0.001). The relations between the difficulty level, need for transfusion, operative time, hepatic pedicle clamping, and major postoperative morbidity were statistically significant (P < 0.05). Linear and nonlinear validation models showed a strong correlation (correlation coefficients 0.914 and 0.948, respectively) with the validated DSS. The Weibull cumulative distribution function was used for predicting the mean risk probability curve of IOC. CONCLUSION: This external validation proved this DSS based on patient's, tumor and surgical factors enables us to estimate the risk of intra- and postoperative complications. A surgeon should be aware of an increased risk of complications before starting with more complex procedures.

Abandonment of surveillance, followed by emergency surgery for a second spontaneous rupture of hepatocellular carcinoma: A case report and review of the literature.

Hepatocellular carcinoma (HCC) develops in the presence of chronic liver disease, and nonalcoholic fatty liver disease is becoming a frequent cause of HCC in developed regions. Spontaneous rupture of HCC (rHCC) is a potentially life-threatening complication of a tumor. The patient's compliance with surveillance after liver resection is vital for the prevention of rHCC.

Simultaneous Pure Laparoscopic Resection of Primary Colorectal Cancer and Synchronous Liver Metastases: A Single Institution Experience with Propensity Score Matching Analysis.

BACKGROUND: The aim of the study was to compare the outcome of pure laparoscopic and open simultaneous resection of both the primary colorectal cancer and synchronous colorectal liver metastases (SCLM). PATIENTS AND METHODS: From 2000 to 2016 all patients treated by simultaneous resection were assessed for entry in this single center, clinically nonrandomized trial. A propensity score matching was used to compare the laparoscopic group (LAP) to open surgery group (OPEN). Primary endpoints were perioperative and oncologic outcomes. Secondary endpoints were overall survival (OS) and disease-free survival (DFS). RESULTS: Of the 82 patients identified who underwent simultaneous liver resection for SCLM, 10 patients underwent LAP. All these consecutive patients from LAP were matched to 10 comparable OPEN. LAP reduced the length of hospital stay (P = 0.044) and solid food oral intake was faster (P = 0.006) in this group. No patient undergoing the laparoscopic procedure experienced conversion to the open technique. No difference was observed in operative time, blood loss, transfusion rate, narcotics requirement, clinical risk score, resection margin, R0 resections rate, morbidity, mortality and incisional hernias rate. The two groups did not differ significantly in terms of the 3-year OS rate (90 vs. 75%; P = 0.842) and DFS rate (60 vs. 57%; P = 0.724). CONCLUSIONS: LAP reduced the length of hospital stay and offers faster solid food oral intake. Comparable oncologic and survival outcomes can be achieved. LAP is beneficial for well selected patients in high volume centers with appropriate expertise.