Contrast-Enhanced Ultrasound for differential diagnosis of pancreatic mass lesions: a meta-analysis.

AIM: To evaluate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) as a method for diagnosing pancreatic lesions with regard to the ductal pancreatic carcinoma and the differentiation of neoplastic from non-neoplastic lesions. MATERIAL AND METHODS: Relevant studies published by September 6, 2015 were retrieved from PubMed, Embase, and Cochrane Central Trials databases. The articles included were mainly based on the following criteria: use of CEUS as the diagnostic tool, and the use of histology as the reference method. Two independent reviewers inspected all these papers to confirm the matching of the inclusion criteria. One reviewer with methodological expertise extracted the data from the included studies. Sensitivity, specificity and diagnostic odds ratio (DOR) were used to obtain overall estimates. RESULTS: Eighteen studies out of 734 articles initially identified met the inclusion criteria. The primary study objective with respect to ductal adenocarcinoma was verified in 15 studies. The pooled estimate of CEUS sensitivity for the differential diagnosis of duct adenocarcinomas was 0.90 (95 % CI, 0.89-0.92), and the specificity was 0.88 (0.84-0.90). The pooled estimate for DOR was 56.38 (29.91-106.33). The area under the curve under the summary receiver operating characteristic (SROC) was 0.95. 12 out of 18 studies examined CEUS sensitivity and the average specificity with regard to the secondary study objective, distinguishing between neoplastic lesions and non-neoplastic lesions, were 0.95 (0.94-0.96) and 0.83 (0.77-0.87). The pooled estimate for DOR was 73.25 (45.31-118.43). The area under the SROC curve was 0.96. CONCLUSIONS: CEUS is a promising, reliable modality for the differential diagnosis of pancreatic adenocarcinoma in patients with pancreatic mass lesions. The presence of a hypoenhanced lesion was a sensitive predictor of pancreatic adenocarcinomas. It seems to be a useful tool in clinical practice.

Imaging findings of bile duct hamartomas: a case report and literature review.

Bile duct hamartomas (BHs), also called von Meyenburg complex (VMC), are benign biliary malformations that originate from disorganization of the small intrahepatic bile ducts. This disorganization is often associated with the abnormal involution of embryonic ductal end plates in the liver. This is clinically significant, as the development of BHs can cause diagnostic confusion with liver metastases and small hepatocellular carcinoma (SHCC). Currently, we report a specific case of BHs and review the literature to better define and diagnose BHs. In the following case, a 37 year-old male bearing a lesion in his liver is presented and undergoes both radiological and pathological diagnosis. The lesion is preliminarily suspected to be a hepatic hemangioma by examination of conventional ultrasound (US), contrast enhanced ultrasound (CEUS), computerized tomographic scanning (CT) and magnetic resonance imaging (MRI). However, SHCC is suspected by follow-up analysis of US and CEUS, due to the patient's background history of hepatitis B and growth of the lesion and a tumor-feeding vessel in BHs via CEUS. However, BHs are finally diagnosed by biopsy pathology under the guidance of ultrasound. Therefore, we believe pathology is imperative for correct diagnosis of BHs over other similar diseases when the imaging findings are atypical. Here we report the novel and unique detection of a tumor-feeding vessel, which mimicked SHCC strongly, during the course of CEUS. We also present a comprehensive review of the previous reported radiological examination related to BHs.

Ultrasound contrast-enhanced imaging and in vitro antitumor effect of paclitaxel-poly(lactic-co-glycolic acid)-monomethoxypoly (ethylene glycol) nanocapsules with ultrasound-targeted microbubble destruction.

A combination of diagnostic and therapeutic ultrasound (US) techniques may be able to provide the basis of specific therapeutic protocols, particularly for the treatment of tumors. Nanotechnology may aid the progression towards the use of US for tumor diagnosis and targeted therapy. The current study investigated in vivo and in vitro US contrast imaging using nanocapsules (NCs), and also US and US­targeted microbubble destruction (UTMD) therapy using drug­loaded NCs for pancreatic cancer in vitro. In the current study, the NCs were made from the polymer nanomaterial poly(lactic­co­glycolic acid)­monomethoxypoly(ethylene glycol) (PLGA­mPEG), encapsulated with paclitaxel (PTX), to create PTX­PLGA­mPEG NCs. The PTX­PLGA­mPEG NCs were used as a US contrast agent (UCA), which produced satisfactory US contrast­enhanced images in vitro and in vivo of the rabbit kidneys, with good contrast compared with lesions in the peripheral regions. However, clear contrast­enhanced images were not obtained using PTX­PLGA­mPEG NCs as a UCA, when imaging the superficial pancreatic tumors of nude mice in vivo. Subsequently, fluorescence and flow cytometry were used to measure the NC uptake rate of pancreatic tumor cells under various US or UTMD conditions. An MTT assay was used to evaluate the efficiency of PTX and PTX­PLGA­mPEG NCs in killing tumor cells following 24 or 48 h of US or UTMD therapy, compared with controls. The specific US or UTMD conditions had been previously demonstrated to be optimal through repeated testing, to determine the conditions by which cells were not impaired and the efficiency of uptake of nanoparticles was highest. The current study demonstrated high cellular uptake rates of PLGA­mPEG NCs and high tumor cell mortality with PTX­PLGA­mPEG NCs under US or UTMD optimal conditions. It was concluded that the use of NCs in US­mediated imaging and antitumor therapy may provide a novel application for US.

Drug-loaded nano-microcapsules delivery system mediated by ultrasound-targeted microbubble destruction: A promising therapy method.

The nano-microcapsules drug delivery system is currently a promising method for the treatment of many types of diseases, particularly tumors. However, the drug delivery efficiency does not reach a satisfactory level to meet treatment demands. Therefore, the effectiveness of delivery needs to be improved. Based on the alterations in the structure and modification of nano-microcapsules, ultrasound-targeted microbubble destruction (UTMD), a safe physical targeted method, may increase tissue penetration and cell membrane permeability, aiding the drug-loaded nano-microcapsules ingress the interior of targeted tissues and cells. The effectiveness and exact mechanism of action of the drug-loaded nano-microcapsules delivery system mediated by UTMD have yet to be fully elucidated. In this study, the latest advancement in UTMD-mediated drug loaded nano-microcapsules system technology was reviewed and the hindrances of UTMD-mediated drug delivery were assessed, in combination with a prospective study. The findings suggested that the drug delivery efficiency of nano-microcapsules mediated by UTMD was distinctly improved. Thus, the UTMD-mediated drug-loaded nano-microcapsules delivery system may significantly improve the efficiency of drug delivery, which may be a promising new therapeutic method.