Comparison of risk-scoring systems in the prediction of outcome after liver resection.

BACKGROUND: Risk prediction techniques commonly used in liver surgery include the American Society of Anesthesiologists (ASA) grading, Charlson Comorbidity Index (CCI) and cardiopulmonary exercise tests (CPET). This study compares the utility of these techniques along with the number of segments resected as predictive tools in liver surgery. METHODS: A review of a unit database of patients undergoing liver resection between February 2008 and January 2015 was undertaken. Patient demographics, ASA, CCI and CPET variables were recorded along with resection size. Clavien-Dindo grade III-V complications were used as a composite outcome in analyses. Association between predictive variables and outcome was assessed by univariate and multivariate techniques. RESULTS: One hundred and seventy-two resections in 168 patients were identified. Grade III-V complications occurred after 42 (24.4%) liver resections. In univariate analysis of CPET variables, ventilatory equivalents for CO2 (VEqCO2) was associated with outcome. CCI score, but not ASA grade, was also associated with outcome. In multivariate analysis, the odds ratio of developing grade III-V complications for incremental increases in VEqCO2, CCI and number of liver segments resected were 1.09, 1.49 and 2.94, respectively. CONCLUSIONS: Of the techniques evaluated, resection size provides the simplest and most discriminating predictor of significant complications following liver surgery.

The pre-operative rate of growth of colorectal metastases in patients selected for liver resection does not influence post-operative disease-free survival.

AIMS: To assess the potential association between the change in diameter of colorectal liver metastases between pre-operative imaging and liver resection and disease-free survival in patients who do not receive pre-operative liver-directed chemotherapy. MATERIALS AND METHODS: Analysis of a prospectively maintained database of patients undergoing liver resection for colorectal liver metastases between 2005 and 2012 was undertaken. Change in tumour size was assessed by comparing the maximum tumour diameter at radiological diagnosis determined by imaging and the maximum tumour diameter measured at examination of the resected specimen in 157 patients. RESULTS: The median interval from first scan to surgery was 99 days and the median increase in tumour diameter in this interval was 38%, equivalent to a tumour doubling time (DT) of 47 days. Tumour DT prior to liver resection was longer in patients with T1 primary tumours (119 days) than T2-4 tumours (44 days) and shorter in patients undergoing repeat surgery for intra-hepatic recurrence (33 days) than before primary resection (49 days). The median disease-free survival of the whole cohort was 1.57 years (0.2-7.3) and multivariate analysis revealed no association between tumour DT prior to surgery and disease-free survival. CONCLUSIONS: The rate of growth of colorectal liver metastases prior to surgery should not be used as a prognostic factor when considering the role of resection.

The Interaction between Diabetes, Body Mass Index, Hepatic Steatosis, and Risk of Liver Resection: Insulin Dependent Diabetes Is the Greatest Risk for Major Complications.

Background. This study aimed to assess the relationship between diabetes, obesity, and hepatic steatosis in patients undergoing liver resection and to determine if these factors are independent predictors of major complications. Materials and Methods. Analysis of a prospectively maintained database of patients undergoing liver resection between 2005 and 2012 was undertaken. Background liver was assessed for steatosis and classified as <33% and ≥33%. Major complications were defined as Grade III-V complications using the Dindo-Clavien classification. Results. 504 patients underwent liver resection, of whom 56 had diabetes and 61 had steatosis ≥33%. Median BMI was 26 kg/m(2) (16-54 kg/m(2)). 94 patients developed a major complication (18.7%). BMI ≥ 25 kg/m(2) (P = 0.001) and diabetes (P = 0.018) were associated with steatosis ≥33%. Only insulin dependent diabetes was a risk factor for major complications (P = 0.028). Age, male gender, hypoalbuminaemia, synchronous bowel procedures, extent of resection, and blood transfusion were also independent risk factors. Conclusions. Liver surgery in the presence of steatosis, elevated BMI, and non-insulin dependent diabetes is not associated with major complications. Although diabetes requiring insulin therapy was a significant risk factor, the major risk factors relate to technical aspects of surgery, particularly synchronous bowel procedures.

Assessment of the value of MRI scan in addition to CT in the pre-operative staging of colorectal liver metastases.

PURPOSE: The aims of this study were to measure the accuracy of computerised tomography (CT) and magnetic resonance imaging (MRI) scans in detecting colorectal liver metastases (CRLM) and to determine if patients who are staged with MRI in addition to CT have longer liver recurrence-free survival compared to those having CT alone in a unit performing routine intra-operative ultrasound. METHODS: A retrospective analysis of patients undergoing liver resection for CRLM was performed. Patients staged pre-operatively with CT or with additional MRI were included and those with additional PET imaging were excluded from survival analysis. Timing and site of tumour recurrence were recorded. RESULTS: During a 7-year period, 303 patients underwent resection for CRLM of whom 47 (15.5 %) were staged with CT alone and 36 (11.9 %) with additional MRI. The overall accuracy of CT (63 %) and MRI (61.9 %) was similar in the detection of tumour nodules (P = 0.905). There was no difference in the rate of intra-hepatic recurrence between groups with 13/47 and 8/36 cases, respectively (P = 0.737). There was no difference in the disease-free survival curves between the groups (P = 0.487). CONCLUSIONS: Our recommendation is that MRI should not be a mandatory imaging modality in referral guidelines for patients with hepatic CRLM, as the cost and delay associated with the scan outweigh any potential benefit in terms of improved sensitivity compared to CT.

Renal dysfunction is an independent risk factor for mortality after liver resection and the main determinant of outcome in posthepatectomy liver failure.

Introduction. The aim of this study was to assess the interaction of liver and renal dysfunction as risk factors for mortality after liver resection. Materials and Methods. A retrospective analysis of 501 patients undergoing liver resection in a single unit was undertaken. Posthepatectomy liver failure (PHLF) was defined according to the International Study Group of Liver Surgery (ISGLS) definition (assessed on day 5) and renal dysfunction according to RIFLE criteria. 90-day mortality was recorded. Results. Twenty-three patients died within 90 days of surgery (4.6%). The lowest mortality occurred in patients without evidence of PHLF or renal dysfunction (2.7%). The mortality rate in patients with isolated PHLF or renal dysfunction was 20% compared to 45% in patients with both. Diabetes (P = 0.028), renal dysfunction (P = 0.030), and PHLF on day 5 (P = 0.011) were independent predictors of 90-day mortality. Discussion. PHLF and postoperative renal dysfunction are independent predictors of 90-day mortality following liver resection but the predictive value for mortality is significantly higher when failure of both organ systems occurs simultaneously.

The Preoperative Assessment of Hepatic Tumours: Evaluation of UK Regional Multidisciplinary Team Performance.

Introduction. In the UK, patients where liver resection is contemplated are discussed at hepatobiliary multidisciplinary team (MDT) meetings. The aim was to assess MDT performance by identification of patients where radiological and pathological diagnoses differed. Materials and Methods. A retrospective review of a prospectively maintained database of all cases undergoing liver resection from March 2006 to January 2012 was performed. The presumed diagnosis as a result of radiological investigation and MDT discussion is recorded at the time of surgery. Imaging was reviewed by specialist gastrointestinal radiologists, and resultswereagreedonby consensus. Results. Four hundred and thirty-eight patients were studied. There was a significant increase in the use of preoperative imaging modalities (P ≤ 0.01) but no change in the rate of discrepant diagnosis over time. Forty-two individuals were identified whose final histological diagnosis was different to that following MDT discussion (9.6%). These included 30% of patients diagnosed preoperatively with hepatocellular carcinoma and 25% with cholangiocarcinoma of a major duct. Discussion. MDT assessment of patients preoperatively is accurate in terms of diagnosis. The highest rate of discrepancies occurred in patients with focal lesions without chronic liver disease or primary cancer, where hepatocellular carcinoma was overdiagnosed and peripheral cholangiocarcinoma underdiagnosed, where particular care should be taken. Additional care should be taken in these groups and preoperative multimodality imaging considered.

Partial Preservation of Segment IV Confers No Benefit When Performing Extended Right Hepatectomy for Colorectal Liver Metastases.

Introduction. Reducing the volume of resected liver parenchyma may lead to lower morbidity and mortality. The aim of this study was to determine whether partial preservation of segment IV leads to improved outcomes when undertaking extended right hepatectomy for colorectal liver metastases (CRLM). Materials and Methods. A retrospective analysis of patients undergoing right-sided hepatectomy for CRLM was performed. Rates of 90-day mortality and organ dysfunction were compared in 117 patients undergoing right hepatectomy (n = 85), partially extended right hepatectomy with preservation of part of segment IV (n = 20), and fully extended right hepatectomy (n = 12). Results. The 90-day mortality rate of those undergoing right hepatectomy (3/85) was similar to that of those undergoing extended right hepatectomy (0/12) (P = 1.000) but lower than that of those undergoing partially extended right hepatectomy (4/20) (P = 0.024). The rates of hepatic and renal dysfunction were similar between patients undergoing right hepatectomy, partially extended or extended hepatectomy. Discussion. Preservation of part of segment IV confers little clinical benefit when performing extended right hepatectomy for CRLM.