Contrast-enhanced ultrasound for evaluating response to pulsed-wave high-intensity focused ultrasound therapy in advanced pancreatic cancer

Evaluations of the combined use of blood- and tissue-based protein biomarkers for pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with a low 5-year survival rate. Biomarkers may be of value for the early diagnosis of pancreatic cancer. This study assessed blood- and tumour tissue-based biomarkers associated with pancreatic cancer.

METHODS

We studied 61 patients who underwent pancreatic resection. Of these 61 patients, 46 patients had PDAC, and 15 patients had inflammatory tumours. Blood and tumour tissue levels of VEGF, hypoxia-inducible factor 1α (HIF-1α) and glucose transporter 1 (GLUT1) were measured.

RESULTS

Blood concentrations of VEGF (p < 0.000001) and HIF-1α (p = 0.000002) were significantly higher in the PDAC group than in the inflammatory tumour group. Tumour tissue concentrations of VEGF (p < 0.000001), HIF-1α (p = 0.000005) and GLUT1 (0.000002) were also significantly higher in the PDAC group. Univariate analyses revealed that age, BMI, and blood levels of CA19-9, VEGF, and HIF-1α were potential predictors of PDAC. Potential predictors of PDAC in tumour tissue were VEGF, HIF-1α and GLUT1. Multivariate analyses found that VEGF was the most powerful independent predictor of PDAC in blood (OR = 1.016; 95% CI: 1.007-1.025; 0.001) and tumour tissue (OR = 1.02; 95% CI: 1.008-1.032, p = 0.001). The cut-off point for blood VEGF was 134.56 pg/ml, with a sensitivity of 97.8%, specificity of 86.7%, PPV of 95.7%, and NPV of 92.9%. The cut-off point for tissue tumour VEGF in PDAC was 208.59 pg/mg, with a sensitivity, specificity, PPV and NPV of 97.7%, 92.9%, 97.7%, and 92.9%, respectively.

CONCLUSIONS

There are significant differences in blood-based biomarkers for differentiating between PDAC and inflammatory tumours of the pancreas. VEGF was an independent predictor of PDAC independent of its addition to the routinely used tumour marker CA19-9 antigen.

Risk factors for unresectable pancreatic cancer following high-intensity focused ultrasound treatment

PURPOSE

Pancreatic cancer is one of the most aggressive malignant tumors with poor prognosis. High-intensity focused ultrasound (HIFU) is an effective and safe treatment option for advanced pancreatic cancer, however, the survival time of patients after the treatment was different. So, the purpose of this study was to evaluate the relationship between the high-risk characteristics and prognosis of unresectable pancreatic cancer after HIFU treatment.

PATIENTS AND METHODS

This prospective study included 30 patients with unresectable pancreatic cancer who received HIFU at Beijing Friendship Hospital. Data on patients' tumor size, pain scores, peripheral blood lymphocyte subsets, CA19-9 and contrast enhanced ultrasound (CEUS) features were collected to assess the relationship with overall survival (OS) after HIFU.

RESULTS

The median OS from the start of HIFU treatment was 159 days, 95% confidence interval (95% CI): 108-210. The levels of pain were determined by visual analogue scale (VAS) score, and the quartile of the score decreased from 6 (2, 7) to 4 (2, 5) immediately after one session of the treatment (p = 0.001). The diagnostic model showed that high post VAS score and decreasing of peripheral CD4+ T cells were significantly correlated with poor prognosis (p < 0.05), and showed good discrimination ability (AUC = 0.848, 95% CI = 0.709-0.987).

CONCLUSION

HIFU can effectively relieve pain in patients with unresectable pancreatic cancer. Post treatment VAS and change of peripheral CD4+ T cells are independent risk factors affecting the prognosis in patients with unresectable pancreatic cancer after HIFU treatment.

Influence factors on registration of three-dimensional contrast-enhanced ultrasound fusion imaging in evaluating the ablative margin - A phantom study

BACKGROUND

Registration of three-dimensional contrast-enhanced ultrasound fusion imaging (3DCEUS-FI) is time-consuming to obtain high success rate.

OBJECTIVE

To investigate the influence factors on registration success rate of 3DCEUS-FI.

METHODS

Water tank phantoms were made to obtain mimicked pre- and post- radiofrequency ablation three-dimensional contrast-enhanced ultrasound (3DCEUS) and CT images. Orthogonal trials were designed according to factors including size, depth, enhancement level of mimicked tumor, diameter and number of mimicked adjacent vessels. Mimicked pre- and post-RFA 3DCEUS images of 72 trials were fused to assess ablative margin (AM) by two radiologists. With CT images as standard, 3DCEUS-FI accuracy was considered as the consistency of AM evaluation. The inter-observer agreement and the influence factors on registration success rates were analyzed.

RESULTS

The intraclass correlation coefficient (ICC) for the consistency of AM evaluation between CT and 3DCEUS-FI in x-axis, y-axis or z-axis was 0.840∼0.948 (P < 0.001). The ICC for inter-observer agreement was 0.840∼0.948 (P < 0.001). The success rates of registration within mimicked vessels with diameter of 2 mm were significantly lower than those with diameter of 3 mm and 4 mm.

CONCLUSIONS

The mimicked AM measured by 3DCEUS-FI had high accuracy and inter-observer agreement. Diameter of the mimicked adjacent vessels was significantly related to success rate of registration.

Early Assessment of Chemoradiotherapy Response for Locally Advanced Pancreatic Ductal Adenocarcinoma by Dynamic Contrast-Enhanced Ultrasound

Objective: To evaluate the value of dynamic contrast-enhanced ultrasound (DCE-US) and quantitative parameters in early prediction of tumor response to chemoradiotherapy (CRT) in patients with locally advanced pancreatic ductal adenocarcinoma (LAPC). Patients and Methods: In this prospective study, patients with biopsy-proved and histopathologically proved LAPC who underwent regular CRT were recruited. DCE-US evaluations were performed before and four months after CRT. SonoVue-enhanced contrast-enhanced ultrasound (CEUS) was performed by an ultrasound system (ACUSON Sequoia; Siemens Medical Solutions, USA) equipped with a 5C1 MHz convex array transducer. Time−intensity curves were created by VueBox software (Bracco, Italy), and various DCE-US quantitative parameters were obtained. Taking Response Evaluation Criteria in Solid Tumors (RECIST) based on computed tomography (CT) or magnetic resonance imaging (MRI) as the gold standard, DCE-US parameters were compared between the treatment responder group (RG) and non-responder group (NRG). The correlation between the DCE-US parameters and the serum carbohydrate antigen 19-9 (CA 19-9) level was also analyzed. Results: Finally, 21 LAPC patients (mean age 59.3 ± 7.2 years) were included. In comparing the RG (n = 18) and NRG (n = 3), no significant change could be found among the mean size of the lesions (31.2 ± 8.1 mm vs. 27.2 ± 8.3 mm, p = 0.135). In comparing the TICs between the two groups, the LAPC lesions in the RG took a longer time to reach peak enhancement and to wash out. Among all the DCE-US parameters, RT (rise time), WiAUC (wash-in area under the curve), WoAUC (wash-out area under the curve) and WiWoAUC (wash-in and wash-out area under the curve) decreased significantly after CRT in the RG (p < 0.05). The RT ratio, WiAUC ratio, WoAUC ratio and WiWoAUC ratio were closely correlated with the change in serum CA 19-9 level in the RG (p < 0.05). Conclusion: DCE-US might be a potential imaging method for non-invasive follow-up for early response in LAPC patients treated by CRT.