INTRODUCTIONMetastatic disease to the liver in colorectal cancer is a common entity that may present synchronously or metachronously. While increasing surgical experience has improved survival outcomes, some evidence suggest that synchronous lesions should be managed differently. This review aims to update current literature on differences between the outcomes and management of synchronous and metachronous disease.

MATERIALS AND METHODSSystematic review of MEDLINE database up till November 2008.

RESULTSDiscrete differences in tumour biology have been identified in separate studies. Twenty-one articles comparing outcomes were reviewed. Definitions of metachronicity varied from anytime after primary tumour evaluation to 1 year after surgery for primary tumour. Most studies reported that synchronous lesions were associated with poorer survival rates (8% to 16% reduction over 5 years). Sixteen articles comparing combined vs staged resections for synchronous tumour showed comparable morbidity and mortality. Benefits over staged resections included shorter hospital stays and earlier initiation of chemotherapy. Suitability for combined resection depended on patient age and constitution, primary tumour characteristics, size and the number of liver metastases, and the extent of liver involvement.

CONCLUSIONSSurgery remains the only treatment option that offers a chance of long-term survival for patients amenable to curative resection. Synchronicity suggests more aggressive disease although a unifying theory for biological differences explaining the disparity in tumour behaviour has not been found. Combined resection of primary tumour and synchronous metastases is a viable option pending careful patient selection and institutional experience. Given the current evidence, management of synchronous and metachronous colorectal liver metastases needs to be individualised to the needs of each patient.

Biomarkers, Tumor ; Colorectal Neoplasms ; mortality ; pathology ; surgery ; Humans ; Liver Neoplasms ; mortality ; secondary ; surgery ; Neoplasms, Multiple Primary ; mortality ; pathology ; surgery ; Neoplasms, Second Primary ; mortality ; pathology ; surgery ; Prognosis

INTRODUCTIONThe 2005 American Association for Study of Liver Diseases (AASLD) diagnostic criteria allow non-invasive diagnosis of hepatocellular carcinoma (HCC) based on their enhancement pattern but we have observed a high incidence of atypical enhancement characteristics in HCC associated with portal vein thrombosis. This study seeks to examine the radiological features of this particular subgroup.

MATERIALS AND METHODSPatients with HCC and portal vein thrombosis who underwent pre-treatment multiphasic CT imaging were drawn from a surgical database. The arterial, portal venous and delayed phase images were assessed qualitatively and quantitatively (with region of interest [ROI] analysis) for lesion hypervascularity and washout. The background enhancement of the left and right lobes of the liver was also quantifi ed by ROI analysis.

RESULTSTwenty-fi ve lesions in 25 patients were selected for analysis. Qualitative analysis showed that 10/25 (40%) lesions demonstrated arterial hypervascularity while 16/25 (64%) lesions showed washout. Ten out of 25 (40%) lesions demonstrated both arterial hypervascularity and washout. Quantitative analysis showed that the average absolute lesion enhancement from precontrast to arterial phases was 49.1 (± 17.1) HU for hypervascular lesions compared to 23.8 (± 16.6) HU for non-hypervascular lesions (P <0.01). The mean absolute enhancement of the background liver parenchyma in the arterial phase was 13.79 (± 7.9) HU for hypervascular lesions compared to 36.6 (± 30.6) HU for non-hypervascular lesions (P = 0.03).

CONCLUSIONA large proportion of HCC with portal vein thrombosis lack characteristic arterial hypervascularity, which may be secondary to compensatory increased arterial supply to the background liver. This is a potential pitfall when applying imaging criteria for diagnosis of HCC.

Adult ; Aged ; Aged, 80 and over ; Carcinoma, Hepatocellular ; complications ; diagnostic imaging ; Female ; Humans ; Liver Neoplasms ; complications ; diagnostic imaging ; Male ; Middle Aged ; Pattern Recognition, Automated ; Portal Vein ; diagnostic imaging ; physiopathology ; Retrospective Studies ; Tomography, X-Ray Computed ; methods ; Venous Thrombosis ; diagnostic imaging ; etiology

INTRODUCTIONThis study aims to determine if the quantitative method of region-of-interest (ROI) analysis of lesion attenuation on CT may be a useful adjunct to the conventional approach of diagnosis by visual assessment in assessing tracer wash-out in hepatocellular carcinomas.

MATERIALS AND METHODSFrom a surgical database of 289 patients from 2 institutions, all patients with complete surgical, pathological and preoperative multiphasic CT scans available for review were selected. For each phase of scanning, HU readings of lesion obtained (Lesion(arterial), Lesion(PV) and Lesion(equilibrium)) were analysed using receiver operating curves (ROC) to determine the optimal method and cut-off value for quantitative assessment of tumour wash-out (Lesion(arterial - equilibrium), Lesion(PV - equilibrium) or Lesion(peak - equilibrium)).

RESULTSNinety-four patients with one lesion each met the inclusion criteria. The area under the curve (AUC) values for Lesion(arterial - equilibrium) (0.941) was higher than the AUC for Lesion(pv - equilibrium) (0.484) and for Lesion(peak - equilibrium) (0.667). Based on ROC analysis, a cut-off of 10HU value for Lesion(arterial - equilibrium) would yield sensitivity and specificity of 91.5% and 80.9%, respectively. ROI analysis detected 9/21 (42.9%) of lesions missed by visual analysis. Combined ROI and visual analysis yields a sensitivity of 82/94 (87.2%) compared to 73/94 (77.7%) for visual analysis alone.

CONCLUSIONUsing a cut-off of 10 HU attenuation difference between the arterial and equilibrium phases is a simple and objective method that can be included as an adjunct to visual assessment to improve sensitivity for determining lesion wash-out on CT.

Adult ; Aged ; Aged, 80 and over ; Carcinoma, Hepatocellular ; diagnosis ; pathology ; surgery ; Confidence Intervals ; Databases, Factual ; Female ; Humans ; Liver ; pathology ; Liver Neoplasms ; diagnosis ; pathology ; surgery ; Male ; Middle Aged ; Preoperative Period ; ROC Curve ; Retrospective Studies ; Sensitivity and Specificity ; Tomography, X-Ray Computed ; instrumentation ; Young Adult

INTRODUCTIONIn this study, we report our initial experience with robotic hepatectomy.

METHODSConsecutive patients who underwent robotic hepatectomy at Singapore General Hospital, Singapore, from February 2013 to February 2015 were enrolled in this study. The difficulty level of operations was graded using a novel scoring system for laparoscopic hepatectomies.

RESULTSDuring the two-year period, five consecutive robotic hepatectomies were performed (one left lateral sectionectomy, one non-anatomical segment II/III resection, one anatomical segment V resection with cholecystectomy, one extended right posterior sectionectomy and one non-anatomical segment V/VI resection). Two hepatectomies were performed for suspected hepatocellular carcinoma, two for solitary liver metastases and one for a large symptomatic haemangioma. The median age of the patients was 53 (range 38-66) years and the median tumour size was 2.5 (range 2.1-7.3) cm. The median total operation time was 340 (range 155-825) minutes and the median volume of blood loss was 300 (range 50-1,200) mL. There were no open conversions and no mortalities or major morbidities (> Clavien-Dindo Grade II). The difficulty level of the operations was graded as low in one case (Score 2), intermediate in three cases (Score 5, 6 and 6) and high in one case (Score 10). There was one minor morbidity, where the patient experienced Grade A bile leakage, which resolved spontaneously. The median length of postoperative hospital stay was 5 (range 4-7) days.

CONCLUSIONOur initial experience confirmed the feasibility and safety of robotic hepatectomy.

Adult ; Aged ; Carcinoma, Hepatocellular ; surgery ; Female ; Follow-Up Studies ; Hepatectomy ; methods ; Humans ; Laparoscopy ; methods ; Length of Stay ; Liver Neoplasms ; surgery ; Male ; Middle Aged ; Operative Time ; Prospective Studies ; Robotics ; Singapore