Gadoxetic acid-enhanced 3.0 T MR imaging versus multidetector-row CT in the detection of colorectal metastases in fatty liver using intraoperative ultrasound and histopathology as a standard of reference.

OBJECTIVE: To compare the diagnostic value of gadoxetic acid-enhanced MRI at 3.0 T with 64-row MDCT in the detection of colorectal liver metastases in diffuse fatty infiltration of the liver after neoadjuvant chemotherapy. METHODS: Twenty-three patients with colorectal liver metastases and at moderate to severe steatosis (25-90%) underwent prospectively preoperative tri-phasic MDCT (Somatom Sensation 64, Siemens) and gadoxetic acid-enhanced MRI (3-T Magnetom Trio, Siemens). All patients underwent surgical resection of liver metastases. Intraoperative ultrasound (IOUS) was carried out, which served as the standard of reference, together with histopathology. RESULTS: Overall, 68 metastases (range, 0.4-6 cm; 31/68 metastases [46%] ≤ 1 cm) were found at histology. MDCT detected 49/68 lesions (72%), and MRI 66/68 (97%, p < 0.001). For lesions ≤ 1 cm, MDCT detected only 13/31 (41.9%) and MRI 29/31 (93%, p < 0.001). Eight false-positive lesions were detected by MDCT, seven small lesions by MRI. There was no statistically significant difference between the two modalities in the detection of lesions > 1 cm (p = 0.250). IOUS detected all metastases and revealed two false-positive diagnoses. CONCLUSION: Gadoxetic acid-enhanced 3.0 T MRI is superior to 64-row MDCT in detecting colorectal liver metastases ≤ 1 cm during preoperative staging in patients with liver steatosis. A combination of MRI and IOUS may further improve the outcome of surgical treatment.

Liver metastases.

Liver metastases are a very common site of distant metastases. Detection and accurate characterization of liver metastases is of importance to guide therapy. A variety of imaging modalities such as US (including contrast agents), MDCT, MRI with liver -specific contrast agents and PET/CT are available for this purpose. This review presents imaging techniques and summarizes the current knowledge, how the different imaging modalities should be used.

Lymph node ratio after curative surgery for intrahepatic cholangiocarcinoma.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is rare but its incidence is rising worldwide. The value of lymph node dissection for ICC is under discussion; the current staging systems do not differentiate between numbers of involved nodes. METHODS: Ninety-three patients who underwent laparotomy for ICC between 1997 and 2007 were identified retrospectively; 46 who underwent curative resection and systematic lymphadenectomy around the hepatoduodenal ligament were analysed further. Univariable and multivariable regression analysis was performed to identify prognostic factors. RESULTS: Tumour size and advanced tumour stage were associated with worse overall and recurrence-free survival in univariable analysis. An increased ratio of positive to total harvested lymph nodes (LNR) was also prognostic for adverse outcome in lymph node-positive patients: crude hazard ratio 8.93 (95 per cent confidence interval (c.i.) 1.52 to 32.50) for overall survival and 8.76 (1.96 to 39.22) for recurrence-free survival. Adjusted hazard ratios for LNR in multivariable regression analysis were 9.81 (1.52 to 43.44) and 10.63 (2.04 to 55.31) respectively. The total number of retrieved lymph nodes was not related to survival or recurrence. CONCLUSION: LNR appears to be a good prognostic factor for survival or recurrence after curative resection for ICC.

Gadoxate-enhanced T 1-weighted MR cholangiography: comparison of 1.5 T and 3.0 T.

PURPOSE: To qualitatively and quantitatively compare gadoxate-enhanced T 1-weighted MR cholangiography at magnetic field strengths of 1.5 T and 3.0 T. MATERIALS AND METHODS: A total of 40 patients with a non-dilated biliary system were retrospectively included in the study. T 1-weighted MR cholangiography 20 min after IV administration of 0.025 mmol/kg gadoxate (Primovist) was performed in 20 patients at 1.5 T and in another 20 patients at 3.0 T. Contrast-to-noise ratios (CNR) of the biliary system (common bile duct - CBD, right hepatic duct - RHD, left hepatic duct - LHD) compared to the periductal tissue were measured. Two radiologists also qualitatively assessed the visibility of the intrahepatic and extrahepatic biliary system using a six-point rating scale. The Mann-Whitney U-test and Pearson's correlation coefficient were used for statistical analysis. RESULTS: The CNRs of the intrahepatic and extrahepatic hepatic bile ducts were significantly higher at 3.0 T. Qualitative analysis showed a significant superiority for 3.0 T in the delineation of the intrahepatic biliary system (RHD, LHD, segmental ducts). CONCLUSION: Gadoxate-enhanced T 1-w MR cholangiography at 3.0 T offers better delineation of the intrahepatic biliary system in comparison to imaging at 1.5 T.

Bevacizumab protects against sinusoidal obstruction syndrome and does not increase response rate in neoadjuvant XELOX/FOLFOX therapy of colorectal cancer liver metastases.

AIM: In patients suffering from colorectal cancer liver metastases, 5-fluorouracil-based chemotherapy plus oxaliplatin ensures superior response rates at the cost of hepatic injury. Knowledge about the consequences of bevacizumab on chemotherapy-induced hepatic injury and tumor response is limited. METHODS: Resected liver specimens from patients of two prospective, non-randomized trials (5-fluorouracil/oxaliplatin+/-bevacizumab) were analyzed retrospectively. Hepatotoxicity to the non-tumor bearing liver was evaluated for sinusoidal obstruction syndrome, hepatic steatosis and fibrosis. Tumor response under chemotherapy was assessed according to Response Evaluation Criteria in Solid Tumors (RECIST). RESULTS: Bevacizumab decreased the severity of the sinusoidal obstruction syndrome. Bevacizumab had no impact on hepatic steatosis and fibrosis. The addition of bevacizumab to chemotherapy had no effect on tumor response compared to combination chemotherapy alone. CONCLUSIONS: This analysis shows that bevacizumab protects against the sinusoidal obstruction syndrome and thus provides the histological explanation of the safe use of bevacizumab prior to liver resection. Furthermore, we show that bevacizumab does not improve tumor response according to RECIST.