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Objectives: To compare a low-tube-voltage with or without high-iodine-load multidetector CT (MDCT) protocol with a normal-tube-voltage, normal-iodine-load (standard) protocol in patients with pancreatic ductal adenocarcinoma (PDAC) with respect to tumour conspicuity and image quality.Methods: Thirty consecutive patients (mean age: 66 years, men/women: 14/16) preoperatively underwent triple-phase 64-channel MDCT examinations twice according to: (i) 120-kV standard protocol (PS; 0.75 g iodine (I)/kg body weight, n = 30) and (ii) 80-kV protocol A (PA; 0.75 g I/kg, n = 14) or protocol B (PB; 1 g I/kg, n = 16). Two independent readers evaluated tumour delineation and image quality blindly for all protocols. A third reader estimated the pancreas-to-tumour contrast-to-noise ratio (CNR). Statistical analysis was performed with the Chi-square test.Results: Tumour delineation was significantly better in PB and PA compared with PS (P = 0.02). The evaluation of image quality was similar for the three protocols (all, P > 0.05). The highest CNR was observed with PB and was significantly better compared to PA (P = 0.02) and PS (P = 0.0002).Conclusion: In patients with PDAC, a low-tube-voltage, high-iodine-load protocol improves tumour delineation and CNR leading to higher tumour conspicuity compared to standard protocol MDCT.Key Points: • Low-tube-voltage high-iodine-load MDCT improves pancreatic cancer conspicuity compared to a standard protocol. • The pancreas-to-tumour attenuation difference increases significantly by reducing the tube voltage. • The radiation exposure dose decreases by reducing the tube voltage. [ABSTRACT FROM AUTHOR]

Background Locoregional pancreatic ductal adenocarcinoma ( PDAC) may progress rapidly and/or disseminate despite having an early stage at diagnostic imaging. A prolonged interval from imaging to resection might represent a risk factor for encountering tumour progression at laparotomy. The aim of this study was to determine the therapeutic window for timely surgical intervention. Methods This observational cohort study included patients with histologically confirmed PDAC scheduled for resection with curative intent from 2008 to 2014. The impact of imaging-to-resection/reassessment ( IR) interval, vascular involvement and tumour size on local tumour progression or presence of metastases at reimaging or laparotomy was evaluated using univariable and multivariable regression. Risk estimates were approximated using hazard ratios ( HRs). Results Median IR interval was 42 days. Of 349 patients scheduled for resection, 82 had unresectable disease (resectability rate 76·5 per cent). The unresectability rate was zero when the IR interval was 22 days or shorter, and was lower for an IR interval of 32 days or less compared with longer waiting times (13 versus 26·2 per cent; HR 0·42, P = 0·021). It was also lower for tumours smaller than 30 mm than for larger tumours (13·9 versus 32·5 per cent; HR 0·34, P < 0·001). Tumours with no or minor vascular involvement showed decreased rates of unresectable disease (20·6 per cent versus 38 per cent when there was major or combined vascular involvement; HR 0·43, P = 0·007). However, this failed to reach statistical significance on multivariable analysis ( P = 0·411), in contrast to IR interval ( P = 0·028) and tumour size ( P < 0·001). Conclusion Operation within 32 days of diagnostic imaging reduced the risk of tumour progression to unresectable disease by half compared with a longer waiting time. The results of this study highlight the importance of efficient clinical PDAC management. [ABSTRACT FROM AUTHOR]

Objectives: To compare respiratory-triggered, free-breathing, and breath-hold DWI techniques regarding (1) image quality, and (2) signal intensity (SI) and ADC measurements in pancreatic ductal adenocarcinoma (PDAC).Methods: Fifteen patients with histopathologically proven PDAC underwent DWI prospectively at 1.5 T (b = 0, 50, 300, 600 and 1,000 s/mm(2)) with the three techniques. Two radiologists, independently and blindly, assigned total image quality scores [sum of rating diffusion images (lesion detection, anatomy, presence of artefacts) and ADC maps (lesion characterisation, overall image quality)] per technique and ranked them. The lesion SI, signal-to-noise ratio, mean ADC and coefficient of variation (CV) were compared.Results: Total image quality scores for respiratory-triggered, free-breathing and breath-hold techniques were 17.9, 16.5 and 17.1 respectively (respiratory-triggered was significantly higher than free-breathing but not breath-hold). The respiratory-triggered technique had a significantly higher ranking. Lesion SI on all b-values and signal-to-noise ratio on b300 and b600 were significantly higher for the respiratory-triggered technique. For respiratory-triggered, free-breathing and breath-hold techniques the mean ADCs were 1.201, 1.132 and 1.253 × 10(-3) mm(2)/s, and mean CVs were 8.9, 10.8 and 14.1 % respectively (respiratory-triggered and free-breathing techniques had a significantly lower mean CV than the breath-hold technique).Conclusion: In both analyses, respiratory-triggered DWI showed superiority and seems the optimal DWI technique for demonstrating PDAC.Key Points: • Diffusion-weighted magnetic resonance imaging is increasingly used to detect pancreatic cancer • Images are acquired using various breathing techniques and multiple b-values • Breathing techniques used: respiratory-triggering, free-breathing and breath-hold • Respiratory-triggering seems the optimal breathing technique for demonstrating pancreatic cancer. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the added value of pre- and intraoperative contrast-enhanced ultrasound (transabdominal, or TCEUS and intraoperative, or ICEUS, respectively) in patients with known or highly suspected colorectal cancer liver metastases (CRLM) who have previously undergone extensive gadobenate dimeglumine (Gd-BOPTA) liver MRI.Methods: Fifteen patients with a total of 31 lesions were included in the comparison of TCEUS vs. MRI and nine patients with a total of 19 lesions were included in the comparison of ICEUS vs. MRI. MRI examinations were performed before TCEUS and ICEUS. The analysis was performed lesion by lesion. Sensitivity, positive predictive value (PPV) and accuracy were calculated and compared.Results: On comparing TCEUS with MRI, sensitivity differed significantly, with values of 87% and 100%, respectively (p value < 0.05), but there was no significant difference in PPV and accuracy. The comparison of ICEUS with MRI, however, showed no significant difference in sensitivity, PPV or accuracy.Conclusions: Transabdominal and intraoperative contrast-enhanced ultrasound have no added value in the preoperative evaluation of patients with CRLM undergoing extensive gadobenate dimeglumine liver MRI. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the accuracy of diffusion-weighted imaging (DWI) in diagnosis of pancreas cancer, to compare DWI with a conventional comprehensive MRI (MRI-c) and to analyse apparent diffusion coefficient (ADC) values of lesions. Thirty-six patients with pancreatic lesions (12 malignant and 24 benign) and 39 patients without lesions were included. MRI-c and DWI (free breathing, b values 0 and 500 s/mm(2)) were performed prospectively and consecutively in a 1.5-T system. The analysis was retrospectively performed blinded by two radiologists in consensus. The sensitivity, specificity, accuracy, and positive and negative predictive values of DWI and MRI-c were 92, 97, 96, 85, 98% and 100, 97, 97, 86, 100%, respectively. Mean ADC values of malignant lesions were significantly lower than those of benign lesions. DWI has a similar accuracy to MRI-c in diagnosis of pancreas cancer. [ABSTRACT FROM AUTHOR]

An editorial is presented which discusses computed tomography (CT) and magnetic resonance imaging (MRI) of pancreatic cancer (PC). It mentions that CT is the recommended method for the evaluation of patients with PC since it provides information on the local extent of the primary tumor as well as on the presence of intra- and extra-abdominal metastases.