[en] This study was performed to evaluate the potential clinical value of concurrent chemotherapy and pulsed high intensity focused ultrasound (HIFU) therapy (CCHT), as well as the safety of pulsed HIFU, for the treatment of unresectable pancreatic cancer. Twelve patients were treated with HIFU from October 2008 to May 2010, and three of them underwent CCHT as the main treatment (the CCHT group). The overall survival (OS), the time to tumor progression (TTP), the complications and the current performance status in the CCHT and non-CCHT groups were analyzed. Nine patients in the non-CCHT group were evaluated to determine why CCHT could not be performed more than twice. The OS of the three patients in the CCHT group was 26.0, 21.6 and 10.8 months, respectively, from the time of diagnosis. Two of them were alive at the time of preparing this manuscript with an excellent performance status, and one of them underwent a surgical resection one year after the initiation of CCHT. The TTP of the three patients in the CCHT group was 13.4, 11.5 and 9.9 months, respectively. The median OS and TTP of the non-CCHT group were 10.3 months and 4.4 months, respectively. The main reasons why the nine patients of the non-CCHT group failed to undergo CCHT more than twice were as follows: pancreatitis (n = 1), intolerance of the pain during treatment (n = 4), palliative use of HIFU for pain relief (n = 1) and a poor physical condition due to disease progression (n = 3). No major complications were encountered except one case of pancreatitis. This study shows that CCHT is a potentially effective and safe modality for the treatment of unresectable pancreatic cancer

[en] To investigate the image quality (IQ) and apparent diffusion coefficient (ADC) of reduced field-of-view (FOV) diffusion-weighted imaging (DWI) of pancreas in comparison with full FOV DWI. In this retrospective study, 2 readers independently performed qualitative analysis of full FOV DWI (FOV, 38 × 38 cm; b-value, 0 and 500 s/mm"2) and reduced FOV DWI (FOV, 28 × 8.5 cm; b-value, 0 and 400 s/mm"2). Both procedures were conducted with a two-dimensional spatially selective radiofrequency excitation pulse, in 102 patients with benign or malignant pancreatic diseases (mean size, 27.5 ± 14.4 mm). The study parameters included 1) anatomic structure visualization, 2) lesion conspicuity, 3) artifacts, 4) IQ score, and 5) subjective clinical utility for confirming or excluding initially considered differential diagnosis on conventional imaging. Another reader performed quantitative ADC measurements of focal pancreatic lesions and parenchyma. Wilcoxon signed-rank test was used to compare qualitative scores and ADCs between DWI sequences. Mann Whitney U-test was used to compare ADCs between the lesions and parenchyma. On qualitative analysis, reduced FOV DWI showed better anatomic structure visualization (2.76 ± 0.79 at b = 0 s/mm"2 and 2.81 ± 0.64 at b = 400 s/mm"2), lesion conspicuity (3.11 ± 0.99 at b = 0 s/mm"2 and 3.15 ± 0.79 at b = 400 s/mm"2), IQ score (8.51 ± 2.05 at b = 0 s/mm"2 and 8.79 ± 1.60 at b = 400 s/mm"2), and higher clinical utility (3.41 ± 0.64), as compared to full FOV DWI (anatomic structure, 2.18 ± 0.59 at b = 0 s/mm"2 and 2.56 ± 0.47 at b = 500 s/mm"2; lesion conspicuity, 2.55 ± 1.07 at b = 0 s/mm"2 and 2.89 ± 0.86 at b = 500 s/mm"2; IQ score, 7.13 ± 1.83 at b = 0 s/mm"2 and 8.17 ± 1.31 at b = 500 s/mm"2; clinical utility, 3.14 ± 0.70) (p < 0.05). Artifacts were significantly improved on reduced FOV DWI (2.65 ± 0.68) at b = 0 s/mm"2 (full FOV DWI, 2.41 ± 0.63) (p < 0.001). On quantitative analysis, there were no significant differences between the 2 DWI sequences in ADCs of various pancreatic lesions and parenchyma (p > 0.05). ADCs of adenocarcinomas (1.061 × 10"-"3 mm"2/s ± 0.133 at reduced FOV and 1.079 × 10"-"3 mm"2/s ± 0.135 at full FOV) and neuroendocrine tumors (0.983 × 10"-"3 mm"2/s ± 0.152 at reduced FOV and 1.004 × 10"-"3 mm"2/s ± 0.153 at full FOV) were significantly lower than those of parenchyma (1.191 × 10"-"3 mm"2/s ± 0.125 at reduced FOV and 1.218 × 10-3 mm"2/s ± 0.103 at full FOV) (p < 0.05). Reduced FOV DWI of the pancreas provides better overall IQ including better anatomic detail, lesion conspicuity and subjective clinical utility

[en] 

Objectives

To differentiate between large (≥ 1 cm in diameter) gallbladder (GB) non-neoplastic and neoplastic polyps using quantitative analysis of contrast-enhanced ultrasound (CEUS) findings.

Methods

From September 2017 to May 2018, 29 patients (10 males; median age, 63 years) with GB polyps of ≥ 1 cm in diameter who were undergoing cholecystectomy were consecutively enrolled. All patients underwent preoperative conventional US and CEUS examinations. Quantitative analysis of CEUS findings using time-intensity curves between the two groups was independently performed by two radiologists. The interobserver agreement for the quantitative analysis of the CEUS results was measured using the intraclass correlation coefficient. Receiver operating characteristic analysis was performed to evaluate the diagnostic performance of CEUS examination.

Results

After the cholecystectomy, the patients were classified into the non-neoplastic polyp group (n = 12) and the neoplastic polyp group (n = 17) according to the pathological results. The interobserver agreement for quantitative assessment between the two radiologists was near perfect to substantial. Quantitative assessment of the CEUS findings revealed that the rise time, mean transit time, time to peak, and fall time of non-neoplastic GB polyps were significantly shorter than those of neoplastic polyps (p < 0.001, p = 0.008, p = 0.013, and p = 0.002, respectively). The sensitivity and specificity of the quantitative CEUS parameters for the differentiation between the two groups were 76.5–100% and 75%, respectively, with an area under the curve of 0.765–0.887.

Conclusions

Quantitative analysis of CEUS findings could be valuable in differentiating GB neoplastic polyps from non-neoplastic polyps.

Key Points

• Quantitative analysis of CEUS findings could be valuable in differentiating gallbladder neoplastic polyps from non-neoplastic polyps.

• Quantitative analysis of CEUS findings in gallbladder polyps provides cut-off values for differentiation between neoplastic polyps and non-neoplastic polyps with near-perfect to substantial interobserver agreement.