Differential diagnosis of solid pancreatic lesions using contrast-enhanced three-dimensional ultrasonography

Differential Diagnosis of Solid Pancreatic Lesions Using Detective Flow Imaging Endoscopic Ultrasonography

The differential diagnosis of solid pancreatic lesions (SPLs) using B-mode endoscopic ultrasonography (EUS) is challenging. Detective flow imaging (DFI) offers the potential for detecting low-flow vessels in the pancreas, thus enhancing diagnostic accuracy. This retrospective study aimed to investigate DFI-EUS findings of SPLs and analyze their differential diagnostic accuracy for pancreatic cancer. We included 104 patients with pathologically confirmed SPLs who underwent EUS between April 2021 and June 2023. Expert endosonographers, blinded to the patients' clinical data, evaluated images obtained through B-mode, eFLOW, and DFI-EUS. The frame rate and vessel detection sensitivity were compared between eFLOW and DFI, and the diagnostic criteria for pancreatic cancer were established. The visualization rate for vessels in SPLs was significantly higher with DFI-EUS (96%) compared to eFLOW (27%). Additionally, DFI showed a superior frame rate, sensitivity (99%), and accuracy (88%) for detecting pancreatic cancer, although with a modest specificity (43%). On DFI-EUS, characteristics such as hypovascularity, peritumoral vessel distribution, or spotty vessel form were suggestive of pancreatic cancer. DFI-EUS significantly improved the visualization of vascular structures within the SPLs, highlighting its efficacy as a diagnostic modality for pancreatic cancer.

Contrast-enhanced ultrasound of solid pancreatic head lesions: a prospective study

OBJECTIVE

To evaluate the role of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of solid pancreatic head lesions (SPHL).

METHODS

This prospective study comprised consecutive patients with SPHL who underwent CEUS evaluation of the pancreas. Findings recorded at CEUS were enhancement patterns (degree, completeness, centripetal enhancement, and percentage enhancement) and presence of central vessels. In addition, time to peak (TTP) and washout time (WT) were recorded. The final diagnosis was based on histopathology or cytology. Multivariate analysis was performed to identify parameters that were significantly associated with pancreatic ductal adenocarcinoma (PDAC).

RESULTS

Ninety-eight patients (median age 53.8 years, 59 males) were evaluated. The final diagnosis was PDAC (n = 64, 65.3%), inflammatory mass (n = 16, 16.3%), neuroendocrine tumor (NET, n = 14, 14.3%), and other tumors (n = 4, 4.1%). Hypoenhancement, incomplete enhancement, and centripetal enhancement were significantly more common in PDAC than non-PDAC lesions (p = 0.001, p = 0.031, and p = 0.002, respectively). Central vessels were present in a significantly greater number of non-PDAC lesions (p = 0.0001). Hypoenhancement with < 30% enhancement at CEUS had sensitivity and specificity of 80.6% and 67.7%, respectively, for PDAC. There was no significant difference in the TTP and WT between PDAC and non - PDAC lesions. However, the WT was significantly shorter in PDAC compared to NET (p = 0.011). In multivariate analysis, lack of central vessels was significantly associated with a PDAC diagnosis.

CONCLUSION

CEUS is a useful tool for the evaluation of SPHL. CEUS can be incorporated into the diagnostic algorithm to differentiate PDAC from non-PDAC lesions.

KEY POINTS

• Hypoenhancement and incomplete enhancement at CEUS were significantly more common in PDAC than in non-PDAC. • Central vessels at CEUS were significantly associated with PDAC. • There was no difference in TTP and WT between PDAC and non-PDAC lesions.

Value of Low-Mechanical-Index Contrast-Enhanced Transabdominal Ultrasound for Diagnosis of Pancreatic Cancer: A Meta-analysis

The incidence and mortality rates of pancreatic cancer (PC) are increasing. It is important to discriminate PC from the other pancreatic lesions; however, differential diagnosis based on conventional transabdominal ultrasound (US) remains challenging even though US is often the first examination performed. Transabdominal contrast-enhanced ultrasound (CEUS) has high diagnostic accuracy for PC. This meta-analysis aimed to examine the utility of low-mechanical-index CEUS with enhancement for PC diagnosis. A systematic meta-analysis of all potentially relevant articles was performed. Fixed-effects or random-effects models were used to investigate pooled sensitivity, specificity, positive likelihood ratio (LR) and negative LR. The study enrolled 983 patients from nine eligible studies. The pooled estimates of sensitivity and specificity were 92% (95% confidence interval [CI]: 0.89-0.94) and 76% (95% CI: 0.71-0.81), respectively. The diagnostic odds ratio (DOR) for CEUS was high (53.62). The area under the summary receiver operating characteristic curve was 0.95. Funnel plots revealed no publication bias, and there was no significant relationship between the DORs and study characteristics, including continent, type of contrast agent, contrast agent dosage and scan phase. Only number of patients affected diagnostic ability. This meta-analysis indicates that CEUS with enhancement pattern is useful for diagnosis of PC.

Anticancer Effect of Heparin-Taurocholate Conjugate on Orthotopically Induced Exocrine and Endocrine Pancreatic Cancer

Simple Summary

Pancreatic cancer has a less than 9% 5-year survival rate among patients because it is very difficult to detect and diagnose early. Combinatorial chemotherapy with surgery or radiotherapy is a potential remedy to treat pancreatic cancer. However, these strategies still have side effects such as hair loss, skin soreness and fatigue. To overcome these side effects, angiogenesis inhibitors such as sunitinib are used to deliver targeted blood vessels around tumor tissues, including pancreatic cancer tumors. It is still controversial whether antiangiogenesis therapy is sufficient to treat pancreatic cancer. So far, many scientists have not been focused on the tumor types of pancreatic cancer when they have developed antipancreatic cancer medication. Here, we used heparin–taurocholate (LHT) as an anticancer drug to treat pancreatic cancer through inhibition of angiogenic growth factors. In this study, we examined the anticancer efficacy of LHT on various types of pancreatic cancer in an orthotopic model.

Abstract

Pancreatic cancers are classified based on where they occur, and are grouped into those derived from exocrine and those derived from neuroendocrine tumors, thereby experiencing different anticancer effects under medication. Therefore, it is necessary to develop anticancer drugs that can inhibit both types. To this end, we developed a heparin–taurocholate conjugate, i.e., LHT, to suppress tumor growth via its antiangiogenic activity. Here, we conducted a study to determine the anticancer efficacy of LHT on pancreatic ductal adenocarcinoma (PDAC) and pancreatic neuroendocrine tumor (PNET), in an orthotopic animal model. LHT reduced not only proliferation of cancer cells, but also attenuated the production of VEGF through ERK dephosphorylation. LHT effectively reduced the migration, invasion and tube formation of endothelial cells via dephosphorylation of VEGFR, ERK1/2, and FAK protein. Especially, these effects of LHT were much stronger on PNET (RINm cells) than PDAC (PANC1 and MIA PaCa-2 cells). Eventually, LHT reduced ~50% of the tumor weights and tumor volumes of all three cancer cells in the orthotopic model, via antiproliferation of cancer cells and antiangiogenesis of endothelial cells. Interestingly, LHT had a more dominant effect in the PNET-induced tumor model than in PDAC in vivo. Collectively, these findings demonstrated that LHT could be a potential antipancreatic cancer medication, regardless of pancreatic cancer types.

Intraoperative contrast-enhanced ultrasound can have a crucial role in surgical decision-making during hepato-pancreatico-biliary surgery - Analysis of impact and input

OBJECTIVE

To assess the impact and procedural input of intraoperative ultrasound (IOUS) with contrast-enhanced ultrasound (CEUS) and ultrasound elastography on surgical decision making during the procedure and consequently the outcome after hepato-pancreatico-biliary (HPB) surgery.

MATERIALS AND METHODS

Data of 50 consecutive patients, who underwent HPB surgery from 04/2018 to 07/2018 were prospectively collected for this study. During surgery, IOUS with a high-resolution ultrasound device using CEUS after bolus injection of 2.4-5 ml dulphur hexafluoride microbubbles using a 6-9 MHz probe and a share wave and strain elastography was performed by an experienced examiner. Process and time analysis were carried out using mobile phone timer.

RESULTS

The IOUS with CEUS and elastography correctly identified 42 malignant tumors and 4 benign lesions. In 3 cases, the examination provided false positive result (identifying 3 benign lesions as malignant) and in 1 case a malignant lesion was incorrectly assessed as benign (sensitivity 97,7%, specificity 57,1%, PPV 93,3% and NPV 80%).The specific question by the surgeon could be answered successfully in 98% of the cases. In 76% of the cases, there was a modification (42%) or a fundamental change (34%) of the planned surgical approach due to the information provided by the IOUS. Within the last group, the IOUS had a major impact on therapy outcome. In 7 patients an additional tumor resection was required, in 5 patients the tumor was assessed as inoperable, and in total in 5 patients an intraoperative RFA (4/5) or postoperative RITA (1/5) was required.Regarding procedural input, there was only a slight, but significant difference between the transport and set-up times before the intraoperative use (mean: 14 min 22 s) and the return transport (mean 13 min 6 s), (p = 0,038). The average examination time was 14 minutes, which makes only one third of the overall time demand.

CONCLUSION

Combination of IOUS with CEUS and elastography in oncological HPB surgery provides valuable information that affects surgical decision-making. The procedural input of about 45 minutes seems to be a good investment considering the improvement of the surgical procedure and a significant modification of the therapy approach in the majority of the cases.

The AFSUMB Consensus Statements and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound using Sonazoid

The first edition of the guidelines for the use of ultrasound contrast agents was published in 2004, dealing with liver applications. The second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some nonliver applications. The third edition of the contrast-enhanced ultrasound (CEUS) guidelines was the joint World Federation for Ultrasound in Medicine and Biology-European Federation of Societies for Ultrasound in Medicine and Biology (WFUMB-EFSUMB) venture in conjunction with other regional US societies such as Asian Federation of Societies for Ultrasound in Medicine and Biology, resulting in a simultaneous duplicate on liver CEUS in the official journals of both WFUMB and EFSUMB in 2013. However, no guidelines were described mainly for Sonazoid due to limited clinical experience only in Japan and Korea. The new proposed consensus statements and recommendations provide general advice on the use of Sonazoid and are intended to create standard protocols for the use and administration of Sonazoid in hepatic and pancreatobiliary applications in Asian patients and to improve patient management.

The AFSUMB Consensus Statements and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound using Sonazoid

The first edition of the guidelines for the use of ultrasound contrast agents was published in 2004, dealing with liver applications. The second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some nonliver applications. The third edition of the contrast-enhanced ultrasound (CEUS) guidelines was the joint World Federation for Ultrasound in Medicine and Biology-European Federation of Societies for Ultrasound in Medicine and Biology (WFUMB-EFSUMB) venture in conjunction with other regional US societies such as Asian Federation of Societies for Ultrasound in Medicine and Biology, resulting in a simultaneous duplicate on liver CEUS in the official journals of both WFUMB and EFSUMB in 2013. However, no guidelines were described mainly for Sonazoid due to limited clinical experience only in Japan and Korea. The new proposed consensus statements and recommendations provide general advice on the use of Sonazoid and are intended to create standard protocols for the use and administration of Sonazoid in hepatic and pancreatobiliary applications in Asian patients and to improve patient management.

Clinical application of dynamic contrast enhanced ultrasound in monitoring the treatment response of chemoradiotherapy of pancreatic ductal adenocarcinoma

OBJECTIVES

To investigate the value of dynamic contrast enhanced ultrasound (D-CEUS) in monitoring the chemoradiotherapy (CRT) therapeutic response of local advanced pancreatic ductal adenocarcinoma (LAPC).

PATIENTS AND METHODS

From October 2017 to December 2018, 11 patients diagnosed as LAPC were included (7 men, 4 women; mean age: 61.1±8.6 years). The algorithm of CRT was as following: the radiotherapy dose was 50.4 Gy/28Fx with S-1 40 mg bid orally taken in radiotherapy day. Conventional ultrasound scan and CEUS were performed before and 4 weeks after CRT. All ultrasound examinations were performed by an ACUSON Oxana 2 ultrasound equipment (Siemens Medical Solutions, Germany) with a C 6-1 convex array transducer (1-6 MHz). Time intensity curves (TICs) were generated in the region of interests (ROIs) both in LAPC lesions and in its surrounding pancreas parenchyma by SonoLiver software (TOMTEC Imaging Systems). Quantitative perfusion parameters including maximum intensity (MI), rise time (RT), mean transit time (mTT) and time to peak (TTP) were analyzed and compared before and after CRT.

RESULTS

No significant difference could be found by conventional B mode ultrasound scan after CRT. TICs of CEUS showed lower ascending and descending slopes rate after CRT. Among all perfusion quantitative parameters, MI decreased significantly after CRT (42.1±18.8% vs 27.8±17.2%, P < 0.05).

CONCLUSIONS

Depending on its unique advantages as non-radiation, effective and convenient, D-CEUS analysis and quantitative parameters, particularly MI, has potential application value in following up of the CRT treatment response in LAPC patients.

Ultrasound diagnosis of pancreatic solid tumors

INTRODUCTION

Advances and widespread use of various diagnostic imaging modalities have dramatically improved our ability to visualize and diagnose pancreatic diseases. In particular, ultrasonography in pancreatic diseases plays an important role from screening to diagnosis as a simple and safe examination method.

METHODS

The basic scanning method of transabdominal pancreatic ultrasonography, characterization, and differential diagnosis by ultrasonography including contrast-enhanced ultrasonography (CEUS) for solid pancreatic tumors are reviewed with reference to various papers.

RESULTS

In recent years, the ability to visualize and diagnose pancreatic mass lesions has been dramatically improved with advances in ultrasound equipment. In particular, CEUS using an ultrasound contrast agent has made it possible to evaluate hemodynamics in organs or lesions as well as in the flow signal of arterial blood vessels, and it has played an important role not only in diagnosis of the presence of a lesion but also in the qualitative diagnosis. The enhancement behavior and pattern with CEUS of pancreatic solid tumors is shown in text and Fig. 9. Moreover, the flow chart for diagnosing pancreatic solid tumors with CEUS classifying the enhancement behavior and pattern for pancreatic solid tumors on CEUS is shown (Fig. 10). In meta-analyses, the pooled sensitivity in the differential diagnosis of pancreatic adenocarcinomas and other pancreatic focal masses with CEUS was 86-90%, and the pooled specificity was 75-88%.

CONCLUSION

CEUS is a minimally invasive and useful diagnostic method that can be used to make a simple and quick qualitative diagnosis of pancreatic diseases. CEUS provides a lot of information important for diagnosis, and has led to changes in the conventional diagnostic systems in pancreatic diseases.

Differential diagnosis of gallbladder polypoid lesions using contrast-enhanced ultrasound

PURPOSE

The purpose of the study is to evaluate the utility of contrast-enhanced ultrasound (CEUS) for the differential diagnosis of gallbladder polypoid lesions (GPLs).

METHODS

Thirty-six patients with GPLs (17 with gallbladder cancer, 19 with benign polyps) who underwent CEUS were enrolled in the study. The mean age of patients was 65.7 ± 12.6 years. Perflubutane-based contrast agent and high-mechanical index mode, which can eliminate the background B-mode and provide precise visualization of tumor vessels, were used for CEUS, and two blinded readers evaluated the images, retrospectively.

RESULTS

Patient age and size of malignant GPLs (72.4 ± 9.4 years and 23.4 ± 7.5 mm) were significantly greater than those for benign lesions (59.6 ± 12.3 years and 12.4 ± 2.9 mm) (P < 0.01, respectively), and the receiver operating characteristic analysis showed the cut-off value as over 65 years and 16 mm. Univariate analysis showed that heterogeneity in B-mode (80% [12/15]), sessile shape (76% [13/17]), dilated vessel (71% [12/17]), irregular vessel (82% [14/17]), and heterogeneous enhancement (59% [10/17]) on CEUS were significantly correlated with malignant GPLs (P < 0.01, respectively). On CEUS, the diagnostic criterion for malignant GPLs was defined as having one or more of the above four features because of the highest accuracy. Sensitivity, specificity, and accuracy for malignant GBLs were 88%, 68%, and 78% for patient age; 76%, 89%, and 83% for size of GPLs; 80%, 68%, and 74% for B-mode; and 94%, 89%, and 92% for CEUS, respectively.

CONCLUSIONS

CEUS is useful for the differential diagnosis of malignant and benign GPLs.

Pancreatic Blood Flow with Special Emphasis on Blood Perfusion of the Islets of Langerhans

The pancreatic islets are more richly vascularized than the exocrine pancreas, and possess a 5- to 10-fold higher basal and stimulated blood flow, which is separately regulated. This is reflected in the vascular anatomy of the pancreas where islets have separate arterioles. There is also an insulo-acinar portal system, where numerous venules connect each islet to the acinar capillaries. Both islets and acini possess strong metabolic regulation of their blood perfusion. Of particular importance, especially in the islets, is adenosine and ATP/ADP. Basal and stimulated blood flow is modified by local endothelial mediators, the nervous system as well as gastrointestinal hormones. Normally the responses to the nervous system, especially the parasympathetic and sympathetic nerves, are fairly similar in endocrine and exocrine parts. The islets seem to be more sensitive to the effects of endothelial mediators, especially nitric oxide, which is a permissive factor to maintain the high basal islet blood flow. The gastrointestinal hormones with pancreatic effects mainly influence the exocrine pancreatic blood flow, whereas islets are less affected. A notable exception is incretin hormones and adipokines, which preferentially affect islet vasculature. Islet hormones can influence both exocrine and endocrine blood vessels, and these complex effects are discussed. Secondary changes in pancreatic and islet blood flow occur during several conditions. To what extent changes in blood perfusion may affect the pathogenesis of pancreatic diseases is discussed. Both type 2 diabetes mellitus and acute pancreatitis are conditions where we think there is evidence that blood flow may contribute to disease manifestations. © 2019 American Physiological Society. Compr Physiol 9:799-837, 2019.

Differentiation of pancreatic neuroendocrine carcinoma from pancreatic ductal adenocarcinoma using magnetic resonance imaging: The value of contrast-enhanced and diffusion weighted imaging

Pancreatic neuroendocrine carcinoma (PNEC) is often misdiagnosed as pancreatic ductal adenocarcinoma (PDAC). This retrospective study differentiated PNEC from PDAC using magnetic resonance imaging (MRI), including contrast-enhanced (CE) and diffusion-weighted imaging (DWI). Clinical data and MRI findings, including the T1/T2 signal, tumor boundary, size, enhancement degree, and apparent diffusion coefficient (ADC), were compared between 37 PDACs and 13 PNECs. Boundaries were more poorly defined in PDAC than PNEC (97.3% vs. 61.5%, p<0.01). Hyper-/isointensity was more common in PNEC than PDAC at the arterial (38.5% vs. 0.0), portal (46.2% vs. 2.7%) and delayed phases (46.2% vs. 5.4%) (all p<0.01). Lymph node metastasis (97.3% vs. 61.5%, p<0.01) and local invasion/distant metastasis (86.5% vs. 46.2%, p<0.01) were more common in PDAC than PNEC. Enhancement degree via CE-MRI was higher in PNEC than PDAC at the arterial and portal phases (p<0.01). PNEC ADC values were lower than those of normal pancreatic parenchyma (p<0.01) and PDAC (p<0.01). Arterial and portal phase signal intensity ratios and ADC values showed the largest areas under the receiver operating characteristic curve and good sensitivities (92.1%–97.2%) and specificities (76.9%–92.3%) for differentiating PNEC from PDAC. Thus the enhancement degree at the arterial and portal phases and the ADC values may be useful for differentiating PNEC from PDAC using MRI.