Imaging of pancreatic cancer: An overview

Diagnosing Pancreatic Adenocarcinoma With Contrast-Enhanced Ultrasonography: A Literature Review of Research in Europe and Asia

The National Cancer Institute names pancreatic cancer the 11^th most common type of cancer in the United States. However, even with a somewhat low prevalence, in 2017, the American Cancer Society reported pancreatic cancer as the fourth leading cause of cancer-related death. With a lack of symptomology and a broad range of risk factors, pancreatic cancer is frequently diagnosed in a later phase than many other types of cancers, thus resulting in higher metastasis along with a poorer prognosis. This highlights the need for early detection and diagnosis. Currently, abdominal ultrasound or contrast-enhanced CT imaging of the abdomen are standard of care. A new technology: contrast-enhanced ultrasound (CEUS), which employs contrast agents to act as acoustic enhancers for ultrasound, has FDA approval for use in hepatic and renal lesions, but not pancreatic. By examining seven individual studies from Europe and Asia, this review aims to examine the diagnostic value of CEUS to initially diagnose pancreatic adenocarcinomas, potentially followed by a biopsy to confirm, when compared against modalities currently used such as conventional ultrasound and CT imaging. CEUS would potentially be more accurate when compared to conventional ultrasound due to the addition of contrast, and when compared against CT and MRI, CEUS would be advantageous in its low cost, similar sensitivities, and specificities, limited renal toxicity, lack of ionizing radiation, short half-life, and its safe use in both adult and pediatric patients. Due to this, additional research is warranted for further FDA approval and future clinical implementation.

Structured CT reporting of pancreatic ductal adenocarcinoma: impact on completeness of information and interdisciplinary communication for surgical planning

PURPOSE

With the rise in popularity of structured reports in radiology, we sought to evaluate whether free-text CT reports on pancreatic ductal adenocarcinoma (PDAC) staging at our institute met published guidelines and assess feedback of pancreatic surgeons comparing free-text and structured report styles with the same information content.

METHODS

We retrospectively evaluated 298 free-text preoperative CT reports from 2015 to 2017 for the inclusion of key tumor descriptors. Two surgeons independently evaluated 50 free-text reports followed by evaluation of the same reports in a structured format using a 7-question survey to assess the usefulness and ease of information extraction. Fisher's exact test and Chi-square test for independence were utilized for categorical responses and an independent samples t test for comparing mean ratings of report quality as rated on a 5-point Likert scale.

RESULTS

The most commonly included descriptors in free-text reports were tumor location (99%), liver lesions (97%), and suspicious lymph nodes (97%). The most commonly excluded descriptors were variant arterial anatomy and peritoneal/omental nodularity, which were present in only 23% and 42% of the reports, respectively. For vascular involvement, a mention of the presence or absence of perivascular disease with the main portal vein was most commonly included (87%). Both surgeons' rating of overall report quality was significantly higher for structured reports (p < 0.001).

CONCLUSION

Our results indicate that free-text reports may not include key descriptors for staging PDAC. Surgeons rated structured reports that presented the same information as free-text reports but in a template format superior for guiding clinical management, convenience of use, and overall report quality.

Applying a radiomics-based CAD scheme to classify between malignant and benign pancreatic tumors using CT images

BACKGROUND

Pancreatic cancer is one of the most aggressive cancers with approximate 10% five-year survival rate. To reduce mortality rate, accurate detection and diagnose of suspicious pancreatic tumors at an early stage plays an important role.

OBJECTIVE

To develop and test a new radiomics-based computer-aided diagnosis (CAD) scheme of computed tomography (CT) images to detect and classify suspicious pancreatic tumors.

METHODS

A retrospective dataset consisting of 77 patients who had suspicious pancreatic tumors detected on CT images was assembled in which 33 tumors are malignant. A CAD scheme was developed using the following 5 steps namely, (1) apply an image pre-processing algorithm to filter and reduce image noise, (2) use a deep learning model to detect and segment pancreas region, (3) apply a modified region growing algorithm to segment tumor region, (4) compute and select optimal radiomics features, and (5) train and test a support vector machine (SVM) model to classify the detected pancreatic tumor using a leave-one-case-out cross-validation method.

RESULTS

By using the area under receiver operating characteristic (ROC) curve (AUC) as an evaluation index, SVM model yields AUC = 0.750 with 95% confidence interval [0.624, 0.885] to classify pancreatic tumors.

CONCLUSIONS

Study results indicate that radiomics features computed from CT images contain useful information associated with risk of tumor malignancy. This study also built a foundation to support further effort to develop and optimize CAD schemes with more advanced image processing and machine learning methods to more accurately and robustly detect and classify pancreatic tumors in future.

The utility of 18F-FDG PET/CT in the diagnosis, staging of non-functioning pancreatic neuroendocrine tumors

Background

The non-functional PNETs are often discovered incidentally, they are commonly malignant and commonly present at a late stage with large size. We evaluate in this study the usefulness of 18F-FDG PET/CT in the detection and staging of non-functioning PNETs.

Results

Thirty patients with non-functioning PNETs were involved in this prospective study over a period starting from September 2016 to March 2021. Age ranged from 33 to 79 years. 18F-FDG PET/CT detected 26 patients had SUV max ≥ 2.5 of primary lesions and 4 lesions had SUV max < 2.5. There was no statistical significant between the site of the lesions and the type of grading of the tumors. 32 distant metastatic lesions were detected which show SUVmax ≥ 2.5 and only 9%where below 2.5. Of 30 patients, 4 patients (13.3%) of well differentiated tumor had altered their clinical strategies according to the results of PET/CT examinations. 18F-FDG PET/CT upstaged 1 patient with stage IB and 3 patients with IIA and B to stage IV.

Conclusion

The increased use of 18F-FDG PET/CT in the investigation of patient with PNETs allows for more accurate staging and therefore more appropriate management decision.

LDL receptor-peptide conjugate as in vivo tool for specific targeting of pancreatic ductal adenocarcinoma

Despite clinical advances in diagnosis and treatment, pancreatic ductal adenocarcinoma (PDAC) remains the third leading cause of cancer death, and is still associated with poor prognosis and dismal survival rates. Identifying novel PDAC-targeted tools to tackle these unmet clinical needs is thus an urgent requirement. Here we use a peptide conjugate that specifically targets PDAC through low-density lipoprotein receptor (LDLR). We demonstrate by using near-infrared fluorescence imaging the potential of this conjugate to specifically detect and discriminate primary PDAC from healthy organs including pancreas and from benign mass-forming chronic pancreatitis, as well as detect metastatic pancreatic cancer cells in healthy liver. This work paves the way towards clinical applications in which safe LDLR-targeting peptide conjugate promotes tumor-specific delivery of imaging and/or therapeutic agents, thereby leading to substantial improvements of the PDAC patient’s outcome.

Acier et al. investigated a peptide cargo system, the Fc(A680)-VH4127, that targets PDAC through the LDLR cell-surface receptor. The Fc(A680)-VH4127 was found to specifically target spontaneous pancreatic tumors in KICmice, as well as metastatic pancreatic tumors in liver.

Tailor-Made Nanomaterials for Diagnosis and Therapy of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers worldwide due to its aggressiveness and the challenge to early diagnosis and treatment. In recent decades, nanomaterials have received increasing attention for diagnosis and therapy of PDAC. However, these designs are mainly focused on the macroscopic tumor therapeutic effect, while the crucial nano-bio interactions in the heterogeneous microenvironment of PDAC remain poorly understood. As a result, the majority of potent nanomedicines show limited performance in ameliorating PDAC in clinical translation. Therefore, exploiting the unique nature of the PDAC by detecting potential biomarkers together with a deep understanding of nano-bio interactions that occur in the tumor microenvironment is pivotal to the design of PDAC-tailored effective nanomedicine. This review will introduce tailor-made nanomaterials-enabled laboratory tests and advanced noninvasive imaging technologies for early and accurate diagnosis of PDAC. Moreover, the fabrication of a myriad of tailor-made nanomaterials for various PDAC therapeutic modalities will be reviewed. Furthermore, much preferred theranostic multifunctional nanomaterials for imaging-guided therapies of PDAC will be elaborated. Lastly, the prospects of these nanomaterials in terms of clinical translation and potential breakthroughs will be briefly discussed.

Diffuse Pancreatic Carcinoma with Hepatic Metastases

Pancreatic cancer is one of the seven leading causes of cancer death worldwide. Diffuse pancreatic carcinoma is very rare and underreported in the literature. Many advances have been made in the diagnosis and management of pancreatic cancer. However, most pancreatic cancer cases are detected at the terminal or metastatic stages. Therefore, timely diagnosis and therapeutic management are desirable goals for this disease. Although the proliferation of pancreatic cancer has been reduced by intervention, more work is needed to treat and prevent the disease. The purpose of this article is to present a case of a 54-year-old male with pancreatic cancer and to review the epidemiology, diagnosis, management, and prevention of pancreatic tumors in general as well as pancreatic carcinoma in particular.

Differentiating benign and malignant pancreatic masses: Ga-68 PSMA PET/CT as a new diagnostic avenue

OBJECTIVE

Differentiation of malignant and benign pancreatic lesions on anatomical imaging is difficult in some cases with overlapping features. Prostate-specific membrane antigen (PSMA) is overexpressed during angioneogenesis in many tumors. We aimed to evaluate the PSMA expression in pancreatic lesions to differentiate these lesions and explore the performance of Ga-68 PSMA-PET/CT vis-a-vis F-18 FDG-PET/CT.

METHODS

Patients with pancreatic lesions on conventional imaging were prospectively recruited. All the patients underwent a whole-body F-18 FDG-PET/CT and a regional abdominal Ga-68 PSMA-PET/CT. Focal tracer uptake (FDG or PSMA) on PET images was considered positive. Histopathology and/or cytopathology were considered the reference standard.

RESULTS

A total of forty patients (27 males, mean age 55.3 ± 9.8, range 37-71 years) were enrolled. Of these, 19 were diagnosed as malignant on histopathology/cytology. Patients with benign lesions showed no worsening of symptoms for at least 6 months on follow-up. FDG-PET/CT revealed 17 true-positive (TP), 9 false-positive (FP), 12 true-negative (TN), and 2 false-negative (FN) findings, whereas PSMA-PET/CT had 18 TP, 2 FP, 19 TN, and 1 FN finding. The sensitivity, specificity, PPV, NPV, and accuracy for FDG-PET/CT were 89.5%, 57.1%, 65.4%, 85.7%, and 72.5%, respectively, while for PSMA-PET/CT were 94.7%, 90.5%, 90%, 95%, and 92.5%, respectively. ROC curve analysis showed that the SUVmax value of 4.8 on PSMA-PET/CT could predict the malignant potential of a lesion with a specificity of 90.5% and a sensitivity of 84.2%.

CONCLUSIONS

Ga-68 PSMA-PET/CT imaging helped in establishing a non-invasive pre-operative diagnosis of primary pancreatic malignancy with a higher degree of specificity and accuracy compared with FDG-PET/CT.

KEY POINTS

• Conventional imaging such as CT and MRI are unable to reliably differentiate localized malignant pancreatic lesion from benign lesions mimicking malignancy such as mass-forming pancreatitis. • FDG PET/CT helps in detecting malignant foci in view of their increased glucose metabolism. However, it may be falsely positive in inflammatory lesions which may occasionally hinder its ability to differentiate between benign and malignant lesions. • Apart from prostatic malignancy, PSMA is overexpressed in neovasculature of many non-prostatic malignancies. The present study highlights that Ga68 PSMA PET/CT performed better in diagnosing malignancy non-invasively than FDG-PET/CT with a higher PPV (90.5% vs. 65.4%) and accuracy (92.5% vs. 72.5%).

Pancreatic Cancer detection via Galectin-1-targeted Thermoacoustic Imaging: validation in an in vivo heterozygosity model

Purpose: To investigate the feasibility of microwave-induced thermoacoustic imaging (MTAI) in detecting small pancreatic tumors (< 10 mm in diameter) and to complement the limitation of current clinical imaging methods.

Methods: A home-made MTAI system composed of a portable antenna and pulsed microwave generator was developed. The thermoacoustic nanoparticles were composed of the galectin-1 antibody for targeting pancreatic tumors and Fe₃O₄ nanoparticles as microwave absorbers (anti-Gal1-Fe₃O₄ nanoparticles). The microwave absorption properties of the nanoparticles were measured with a vector network analyzer and the resolving power of MTAI was investigated by imaging excised pancreatic tumors of different sizes (diameters of 1.0 mm, 3.1 mm, 5.0 mm, 7.2 mm). To simulate actual imaging scenarios, an in vivo heterozygosity model was constructed by covering the pancreatic tumors (~ 3 mm in diameter) in BALB/c nude mice with biologic tissue (~ 5 cm in depth). MTAI images of the heterozygosity model were acquired with/without the injection of the anti-Gal1-Fe₃O₄ nanoparticles and the thermoacoustic contrast from pancreatic tumors was evaluated with Student's paired t test. The data were analyzed with analysis of variance and nonparametric statistics.

Results: Following intravenous infusion, anti-Gal1-Fe₃O₄ nanoparticles efficiently accumulated in the tumor. The MTAI contrast enhancement in pancreatic tumors with anti-Gal1-Fe₃O₄ nanoparticles was verified in vitro and in vivo. The pancreatic tumors were visible in nude mice examined with MTAI with a mean contrast enhancement ratio of 2.3 ± 0.15 (standard error of the mean) (P =. 001) at 6 h post-injection of the nanoparticles. MTAI identified tiny pancreatic tumors in deep tissues with high fidelity.

Conclusion: MTAI offers deep imaging depth and high contrast when used with anti-Gal1-Fe₃O₄ nanoparticles. It can identify pancreatic tumors smaller than 5 mm, which is beyond the identification limit size (~10 mm) of other nondestructive clinical imaging methods. Thus, MTAI has great potential as an alternative imaging modality for early pancreatic cancer detection.

Comparative analysis and assessment of diagnostic accuracy of 256 slice CT and endoscopic ultrasound in evaluation of pancreatic masses

CONTEXT

Pancreatic masses are routinely encountered on imaging and often present as a diagnostic dilemma. These masses range from benign inflammatory masses, requiring no intervention to malignant masses, which carry grave prognosis and hence require aggressive management.

AIMS

Compare the diagnostic accuracy of 256 multislice CT and endoscopic ultrasound (EUS) in characterization and assessment of resectability of pancreatic masses and compare the multidetector computed tomography (MDCT) and EUS findings with histopathological findings.

SETTINGS AND DESIGN

Prospective study.

SUBJECTS AND METHODS

36 patients with pancreatic masses were included who underwent dual phase CT using pancreatic protocol and EUS using 5-13 MHz transducer. Fine needle aspiration cytology (FNAC) was done wherever feasible. Parameters regarding tumor size, location, imaging morphology, and vessel involvement were recorded. Findings were compared with histopathological/operative diagnosis/clinical follow-up.

STATISTICAL ANALYSIS USED

Descriptive statistics with percentages and proportions and Chi-square test.

RESULTS

Multidetector computed tomography (MDCT) and EUS established diagnosis consistent with tissue diagnosis in 30 (83%) and 22 (61%) patients, respectively. However, the best results were obtained with the combined use of MDCT and EUS. The number of patients categorized as inconclusive by MDCT were lower compared to EUS. Assessing resectability for pancreatic adenocarcinoma, MDCT showed specificity and positive predictive value (PPV) of 100% compared to EUS, which had specificity and PPV of 75% and 92.3%, respectively. MDCT is the first-line imaging modality in detection, characterization of pancreatic masses, and assessment of resectability in malignant neoplasms. EUS is beneficial in the detection of masses <2 cm in size causing pancreatic contour deformity on CT, for guiding FNAC. MDCT and EUS with EUS-guided FNA are complementary not competitive tools in preoperative imaging of pancreatic masses.

Clinical Translation of a 68Ga-Labeled Integrin αvβ6-Targeting Cyclic Radiotracer for PET Imaging of Pancreatic Cancer

The overexpression of integrin α_vβ₆ in pancreatic cancer makes it a promising target for noninvasive PET imaging. However, currently, most integrin α_vβ₆-targeting radiotracers are based on linear peptides, which are quickly degraded in the serum by proteinases. Herein, we aimed to develop and assess a ⁶⁸Ga-labeled integrin α_vβ₆-targeting cyclic peptide (⁶⁸Ga-cycratide) for PET imaging of pancreatic cancer. Methods: ⁶⁸Ga-cycratide was prepared, and its PET imaging profile was compared with that of the linear peptide (⁶⁸Ga-linear-pep) in an integrin α_vβ₆-positive BxPC-3 human pancreatic cancer mouse model. Five healthy volunteers (2 women and 3 men) underwent whole-body PET/CT imaging after injection of ⁶⁸Ga-cycratide, and biodistribution and dosimetry were calculated. PET/CT imaging of 2 patients was performed to investigate the potential role of ⁶⁸Ga-cycratide in pancreatic cancer diagnosis and treatment monitoring. Results: ⁶⁸Ga-cycratide exhibited significantly higher tumor uptake than did ⁶⁸Ga-linear-pep in BxPC-3 tumor-bearing mice, owing-at least in part-to markedly improved in vivo stability. ⁶⁸Ga-cycratide could sensitively detect the pancreatic cancer lesions in an orthotopic mouse model and was well tolerated in all healthy volunteers. Preliminary PET/CT imaging in patients with pancreatic cancer demonstrated that ⁶⁸Ga-cycratide was comparable to ¹⁸F-FDG for diagnostic imaging and postsurgery tumor relapse monitoring. Conclusion: ⁶⁸Ga-cycratide is an integrin α_vβ₆-specific PET radiotracer with favorable pharmacokinetics and a favorable dosimetry profile. ⁶⁸Ga-cycratide is expected to provide an effective noninvasive PET strategy for pancreatic cancer lesion detection and therapy response monitoring.

Quantitative Magnetic Resonance Imaging of the Pancreas of Individuals With Diabetes

Magnetic resonance imaging (MRI) has the potential to improve our understanding of diabetes and improve both diagnosis and monitoring of the disease. Although the spatial resolution of MRI is insufficient to directly image the endocrine pancreas in people, the increasing awareness that the exocrine pancreas is also involved in diabetes pathogenesis has spurred new MRI applications. These techniques build upon studies of exocrine pancreatic diseases, for which MRI has already developed into a routine clinical tool for diagnosis and monitoring of pancreatic cancer and pancreatitis. By adjusting the imaging contrast and carefully controlling image acquisition and processing, MRI can quantify a variety of tissue pathologies. This review introduces a number of quantitative MRI techniques that have been applied to study the diabetic pancreas, summarizes progress in validating and standardizing each technique, and discusses the need for image analyses that account for spatial heterogeneity in the pancreas.

ALPPL2 Is a Potential Diagnostic Biomarker for Pancreatic Cancer-Derived Extracellular Vesicles

Pancreatic cancer is an aggressive malignancy that often goes undiagnosed in the early stages. Non-invasive, early, and accurate diagnosis is therefore undoubtedly the "holy grail" of pancreatic cancer research. However, despite extensive research efforts, there is no definitive biomarker for this cancer. Previously, we identified alkaline phosphatase placental-like 2 (ALPPL2) as a diagnostic biomarker for pancreatic ductal adenocarcinoma and developed a 2'-fluoro modified RNA aptamer toward it. In this study, we show that ALPPL2 is present in pancreatic cancer extracellular vesicles (EVs) and therefore has potential application in liquid biopsy-based diagnostic strategies. We also developed ALPPL2 direct and sandwich aptamer-linked immobilized sorbent assay (ALISA) for EVs, which could sensitively and specifically detect the protein. We believe that our ALISA format may have a potential diagnostic utility in screening pancreatic-cancer-derived EVs.

A biomimetic pancreatic cancer on-chip reveals endothelial ablation via ALK7 signaling

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive, lethal malignancy that invades adjacent vasculatures and spreads to distant sites before clinical detection. Although invasion into the peripancreatic vasculature is one of the hallmarks of PDAC, paradoxically, PDAC tumors also exhibit hypovascularity. How PDAC tumors become hypovascular is poorly understood. We describe an organotypic PDAC-on-a-chip culture model that emulates vascular invasion and tumor-blood vessel interactions to better understand PDAC-vascular interactions. The model features a 3D matrix containing juxtaposed PDAC and perfusable endothelial lumens. PDAC cells invaded through intervening matrix, into vessel lumen, and ablated the endothelial cells, leaving behind tumor-filled luminal structures. Endothelial ablation was also observed in in vivo PDAC models. We also identified the activin-ALK7 pathway as a mediator of endothelial ablation by PDAC. This tumor-on-a-chip model provides an important in vitro platform for investigating the process of PDAC-driven endothelial ablation and may provide a mechanism for tumor hypovascularity.

Paraneoplastic Opsoclonus Myoclonus in a Patient with Pancreatic Adenocarcinoma

Opsoclonus myoclonus syndrome (OMS) is an extremely rare neurological syndrome typically affecting as few as 1 in 10,000,000 people annually. OMS is characterized by the presence of involuntary, saccadic eye movements, as well as ataxia, including gait incoordination, rigidity, and tremor. The origin of OMS is unclear, but a significant percentage of OMS cases are indicative of an underlying malignancy, most commonly neuroblastoma and small cell lung cancer. Here we describe an adult patient with OMS, who was ultimately diagnosed with a small ductal adenocarcinoma of the pancreas. To our knowledge, this is the third published report of an association between OMS and pancreatic malignancy, and the only case where the pancreatic malignancy was detected prior to metastasis or autopsy at death. This case report highlights the importance of careful, aggressive malignancy screening with OMS, as the pancreatic duct cut-off sign may be overlooked if pancreatic malignancy is not suspected.

Development of novel diagnostic system for pancreatic cancer, including early stages, measuring mRNA of whole blood cells

Pancreatic ductal adenocarcinoma (PDAC) is the most life-threating disease among all digestive system malignancies. We developed a blood mRNA PDAC screening system using real-time detection PCR to detect the expression of 56 genes, to discriminate PDAC from noncancer subjects. We undertook a clinical study to assess the performance of the developed system. We collected whole blood RNA from 53 PDAC patients, 102 noncancer subjects, 22 patients with chronic pancreatitis, and 23 patients with intraductal papillary mucinous neoplasms in a per protocol analysis. The sensitivity of the system for PDAC diagnosis was 73.6% (95% confidence interval, 59.7%-84.7%). The specificity for noncancer volunteers, chronic pancreatitis, and patients with intraductal papillary mucinous neoplasms was 64.7% (54.6%-73.9%), 63.6% (40.7%-82.8%), and 47.8% (26.8%-69.4%), respectively. Importantly, the sensitivity of this system for both stage I and stage II PDAC was 78.6% (57.1%-100%), suggesting that detection of PDAC by the system is not dependent on the stage of PDAC. These results indicated that the screening system, relying on assessment of changes in mRNA expression in blood cells, is a viable alternative screening strategy for PDAC.

Gastric adenocarcinoma causing biliary obstruction without ductal dilatation: a case report

Introduction

Gastric adenocarcinoma is a known complication of partial gastrectomy. Jaundice from gastric adenocarcinoma usually occurs in the setting of hepatic nodal or parenchymal metastasis. This case demonstrates an unusual level of biliary obstruction from gastric adenocarcinoma.

Case presentation

An 84-year-old Caucasian man was diagnosed as having a new gastric adenocarcinoma at the level of the gastroenteric anastomosis of a prior Billroth II gastrectomy after presenting with painless jaundice. He had a non-dilated biliary tree on radiographic imaging despite evidence of large bile duct obstruction on liver biopsy. The obstruction was managed with endoscopic wire-guided stenting of the malignant tumor.

Conclusions

The unusual finding of a non-dilated biliary tree in the face of obstructive jaundice is likely to have resulted from the unusual post-surgical anatomy and hence distal level of obstruction. Endoscopic duodenal stenting is a novel method of managing obstructive jaundice in gastric adenocarcinoma.

Investigating a novel split-filter dual-energy CT technique for improving pancreas tumor visibility for radiation therapy

Purpose

Tumor delineation using conventional CT images can be a challenge for pancreatic adenocarcinoma where contrast between the tumor and surrounding healthy tissue is low. This work investigates the ability of a split‐filter dual‐energy CT (DECT) system to improve pancreatic tumor contrast and contrast‐to‐noise ratio (CNR) for radiation therapy treatment planning.

Materials and methods

Multiphasic scans of 20 pancreatic tumors were acquired using a split‐filter DECT technique with iodinated contrast medium, OMNIPAQUE^TM. Analysis was performed on the pancreatic and portal venous phases for several types of DECT images. Pancreatic gross target volume (GTV) contrast and CNR were calculated and analyzed from mixed 120 kVp‐equivalent images and virtual monoenergetic images (VMI) at 57 and 40 keV. The role of iterative reconstruction on DECT images was also investigated. Paired t‐tests were used to assess the difference in GTV contrast and CNR among the different images.

Results

The VMIs at 40 keV had a 110% greater image noise compared to the mixed 120 kVp‐equivalent images (P < 0.0001). VMIs at 40 keV increased GTV contrast from 15.9 ± 19.9 HU to 93.7 ± 49.6 HU and CNR from 1.37 ± 2.05 to 3.86 ± 2.78 in comparison to the mixed 120 kVp‐equivalent images. The iterative reconstruction algorithm investigated decreased noise in the VMIs by about 20% and improved CNR by about 30%.

Conclusions

Pancreatic tumor contrast and CNR were significantly improved using VMIs reconstructed from the split‐filter DECT technique, and the use of iterative reconstruction further improved CNR. This gain in tumor contrast may lead to more accurate tumor delineation for radiation therapy treatment planning.

PET-based Treatment Response Assessment for Neoadjuvant Chemoradiation in Pancreatic Adenocarcinoma: An Exploratory Study

PURPOSE: Performance of anatomical metrics of Response Evaluation Criteria in Solid Tumors (RECIST1.1) versus Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST1.0) for neoadjuvant chemoradiation (nCR) of pancreatic adenocarcinoma was evaluated based on the pathological treatment response (PTR) data. METHODS AND MATERIALS: The pre- and post-nCR CT and PET data for 14 patients with resectable or borderline resectable pancreatic head adenocarcinoma treated with nCR followed by surgery were retrospectively analyzed. These data were compared with the PTR which were graded according to tumor cell destruction (cellularity), with Grade 0, 1, 2 or 3 (G0, G1, G2 or G3) for complete, moderate, minimal and poor responses, respectively. Maximum standardized uptake value (SUVmax) was defined using body-weight (SUVbw). PERCIST1.0 was defined using lean-body mass normalized SUV (SUVlb or SUL). RECIST1.1 was defined by contouring the whole pancreas head on the CT image. Pre- and post-SUL-peak and SUVmax, RECIST1.1 and PETRECIST1.0 were correlated with PTR using Pearson’s correlation coefficient test. RESULTS: The average mean and SD in SUL-peak for all patients analyzed were lower in post-nCR (3.63±1.06) compared to those at pre-nCR (4.29±0.89). Using PERCIST1.0, 62% of patients showed stable metabolic disease (SMD), 23% partial metabolic response (PMR), and 15% progressive metabolic disease (PMD). Using RECIST1.1, 85% of patients showed stable disease (SD), 8% partial response (PR), and 7% progressive diseases (PD). A poor insignificant correlation was established between PRT and PERECIST1.0 (r=0.121), whereas no correlation was seen with RECIST1.1. CONCLUSIONS: PERCIST1.0 appears to increase the chance of detecting patients with progressive disease compared to the conventional anatomical-based assessment of RECIST1.1. The integration of these additional radiographic metrics in assessing treatment response to nCR for pancreatic adenocarcinoma may provide a promising strategy to better select patients that are most suitable for therapeutic intensification.

Advances in Diagnostic and Intraoperative Molecular Imaging of Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis. To improve outcomes, there is a critical need for improved tools for detection, accurate staging, and resectability assessment. This could improve patient stratification for the most optimal primary treatment modality. Molecular imaging, used in combination with tumor-specific imaging agents, can improve established imaging methods for PDAC. These novel, tumor-specific imaging agents developed to target specific biomarkers have the potential to specifically differentiate between malignant and benign diseases, such as pancreatitis. When these agents are coupled to various types of labels, this type of molecular imaging can provide integrated diagnostic, noninvasive imaging of PDAC as well as image-guided pancreatic surgery. This review provides a detailed overview of the current clinical imaging applications, upcoming molecular imaging strategies for PDAC, and potential targets for imaging, with an emphasis on intraoperative imaging applications.

Glycoprotein biomarkers for the detection of pancreatic ductal adenocarcinoma

Pancreatic cancer (PaC) shows a clear tendency to increase in the next years and therefore represents an important health and social challenge. Currently, there is an important need to find biomarkers for PaC early detection because the existing ones are not useful for that purpose. Recent studies have indicated that there is a large window of time for PaC early detection, which opens the possibility to find early biomarkers that could greatly improve the dismal prognosis of this tumor. The present manuscript reviews the state of the art of the existing PaC biomarkers. It focuses on the anomalous glycosylation process and its role in PaC. Glycan structures of glycoconjugates such as glycoproteins are modified in tumors and these modifications can be detected in biological fluids of the cancer patients. Several studies have found serum glycoproteins with altered glycan chains in PaC patients, but they have not shown enough specificity for PaC. To find more specific cancer glycoproteins we propose to analyze the glycan moieties of a battery of glycoproteins that have been reported to increase in PaC tissues and that can also be found in serum. The combination of these new candidate glycoproteins with their aberrant glycosylation together with the existing biomarkers could result in a panel, which would expect to give better results as a new tool for early diagnosis of PaC and to monitor the disease.

Diagnostic performance of endoscopic ultrasound for detection of pancreatic malignancy following an indeterminate multidetector CT scan: a systemic review and meta-analysis

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis in part due to delayed diagnosis. Even with advances in cross-sectional imaging, small pancreatic malignancies can be missed. We sought to determine the performance of endoscopic ultrasound (EUS) in those without an obvious mass on multi-detector CT scan (MDCT), but with clinical suspicion for pancreatic malignancy.

METHODS

Multiple databases were systematically searched to identify studies that assessed the diagnostic performance of EUS after negative or inconclusive pancreatic protocol MDCT for detection of pancreatic malignancy when clinically suspected. A total of four studies met the inclusion criteria. The point estimates in each study were compared to the summary pooled estimates of sensitivity and specificity with the aid of forest plots. Funnel plots and Egger's test were employed to evaluate possible publication bias.

RESULTS

EUS-guided fine needle aspiration was performed in all studies. EUS was performed in 206 subjects with a clinical suspicion of a pancreatic mass but with an indeterminate MDCT. A pancreatic mass (mean size 21 ± 1.2 mm) was identified in 70% (n = 144) of the subjects, and 42.2% (n = 87) were diagnosed with PDAC. The pooled estimates of EUS for diagnosing pancreatic malignancy in the setting of an indeterminate MDCT were a sensitivity of 85% (95% CI 69-94%), specificity of 58% (95% CI 40-74%), positive predictive value of 77% (69-84%), negative predictive value of 66% (95% CI 53-77%), and an accuracy of 75% (95% CI 67-82). The summary area under the ROC curve was 0.80 (95% CI 0.52-0.89). The funnel plots and Egger's test did not show a significant publication bias.

CONCLUSIONS

The yield of EUS is comparatively higher for the diagnosis of a pancreatic malignancy in patients with suspected cancer, but a non-diagnostic MDCT. Importantly, the majority of the lesions missed on CT represent PDAC, in which early diagnosis is essential.

Pancreatic imaging: Current status of clinical practices and small animal studies

Different causative factors acting on the pancreas can result in diseases such as pancreatitis, diabetes and pancreatic tumors. The high incidence and mortality of pancreatic diseases have placed diagnostic imaging in a crucial position in daily clinical practice. In this mini-review article different pancreatic imaging techniques are discussed, from the standard clinical imaging modalities and state of the art clinical magnetic resonance imaging techniques to current situations in pre-clinical pancreatic imaging studies. In particular, the challenges of pre-clinical rodent pancreatic imaging are addressed, with both the image acquisition techniques and the post-processing methods for rodent pancreatic imaging elaborated.

Incremental Role of Fluorine 18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Assessment of Computed Tomography-Inconspicuous Pancreatic Lesions

Background: Pancreatic malignancies encompass a heterogenous group of disorders, with poor prognosis at diagnosis. Traditionally, conventional computed tomography (CT) has been used for diagnosis, staging, and follow up. However, this technique lacks functional information; and is limited in diagnosis of occult pancreatic disease. Hybrid imaging in the form of positron emission tomography (PET)/CT provides a potential avenue for early detection and subsequent appropriate therapy.

Case Presentation: A 60-year-old male, with a history of abdominal aortic aneurysm which was repaired, came with a complaint of 2 months history of back pain, radiating to the front. The pain was relieved on leaning forward, and aggravated by lying on his back. CT angiography of the abdomen was done, which revealed a concealed aortic aneurysm and a significant atrophy of the pancreatic tail. The serum cancer antigen (CA) 19-9 was elevated (50.0 U/mL, reference range 0.0–37.0 U/mL). At this juncture, the PET scan done revealed no discernible abnormalities. Patient was put on close follow-up in view of the rising trend of CA 19-9 levels. Three months following the initial scans, a repeat ¹⁸F-FDG (fluorine 18 fluorodeoxyglucose) PET/CT revealed an FDG-avid lesion at the neck of the pancreas on PET without perceptible changes on the correlated CT. A Whipple's procedure ensued, with histopathological examination findings of pancreatic adenocarcinoma.

Conclusion: This article discusses the role of PET/CT in the early diagnosis of inconspicuous pancreatic lesions; which could have averted immediate medical therapy.

Selection of optimal molecular targets for tumor-specific imaging in pancreatic ductal adenocarcinoma

Discrimination of pancreatic ductal adenocarcinoma (PDAC) from chronic pancreatitis (CP) or peritumoral inflammation is challenging, both at preoperative imaging and during surgery, but it is crucial for proper therapy selection. Tumor-specific molecular imaging aims to enhance this discrimination and to help select and stratify patients for resection. We evaluated various biomarkers for the specific identification of PDAC and associated lymph node metastases. Using immunohistochemistry (IHC), expression levels and patterns were investigated of integrin αvβ6, carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), Cathepsin E (Cath E), epidermal growth factor receptor (EGFR), hepatocyte growth factor receptor (c-MET), thymocyte differentiation antigen 1 (Thy1), and urokinase-type plasminogen activator receptor (uPAR). In a first cohort, multiple types of pancreatic tissue were evaluated (n=62); normal pancreatic tissue (n=8), CP (n=7), PDAC (n=9), tumor associated lymph nodes (n=32), and PDAC after neoadjuvant radiochemotherapy (n=6). In a second cohort, tissues were investigated (n=55) with IHC and immunofluorescence (IF) for concordance of biomarker expression in all tissue types, obtained from an individual patient. Integrin αvβ6 and CEACAM5 showed significantly higher expression levels in PDAC versus normal pancreatic tissue (P=0.001 and P<0.001, respectively) and CP (P=0.003 and P<0.001, respectively). Avβ6 and CEACAM5 expression identified tumor-positive lymph nodes correctly in 84% and 68%, respectively, and in 100% of tumor-negative nodes for both biomarkers. In conclusion, αvβ6 and CEACAM5 are excellent biomarkers to differentiate PDAC from surrounding tissue and to identify lymph node metastases. Individually or combined, these biomarkers are promising targets for tumor-specific molecular imaging of PDAC.

Current Status and Future Directions for Screening Patients at High Risk for Pancreatic Cancer

It is well known that pancreatic ductal adenocarcinoma has a high mortality rate. Despite progress in understanding the biology and genetic basis of this disease, life expectancy has changed minimally in the last 50 years. This article highlights the importance of screening patients at high risk for developing pancreatic cancer and reviews current methods as well as methods in development for pancreatic cancer early detection and surveillance.

Investigation into the Biological Impact of Block Size on Cathepsin S-Degradable HPMA Copolymers

N-(2-Hydroxypropyl)methacrylamide (HPMA) copolymers have been studied as an efficient carrier for drug delivery and tumor imaging. However, as with many macromolecular platforms, the substantial accumulation of HPMA copolymer by the mononuclear phagocyte system (MPS)-associated tissues, such as the blood, liver, and spleen, has inhibited its clinical translation. Our laboratory is pursuing approaches to improve the diagnostic and radiotherapeutic effectiveness of HPMA copolymers by reducing the nontarget accumulation. Specifically, we have been investigating the use of a cathepsin S (Cat S)-cleavable peptidic linkers to degrade multiblock HPMA copolymers to increase MPS-associated tissue clearance. In this study, we further our investigation into this area by exploring the impact of copolymer block size on the biological performance of Cat S-degradable HPMA copolymers. Using a variety of in vitro and in vivo techniques, including dual labeling of the copolymer and peptide components, we investigated the constructs using HPAC pancreatic ductal adenocarcinoma models. The smaller copolymer block size (S-CMP) demonstrated significantly faster Cat S cleavage kinetics relative to the larger system (L-CMP). Confocal microscopy demonstrated that both constructs could be much more efficiently internalized by human monocyte-differentiated macrophage (hMDM) compared to HPAC cells. In the biodistribution studies, the multiblock copolymers with a smaller block size exhibited faster clearance and lower nontarget retention while still achieving good tumor targeting and retention. Based on the radioisotopic ratios, fragmentation and clearance of the copolymer constructs were higher in the liver compared to the spleen and tumor. Overall, these results indicate that block size plays an important role in the biological performance of Cat S-degradable polymeric constructs.

Functional Single-Chain Polymer Nanoparticles: Targeting and Imaging Pancreatic Tumors in Vivo

The development of tools for the early diagnosis of pancreatic adenocarcinoma is an urgent need in order to increase treatment success rate and reduce patient mortality. Here, we present a modular nanosystem platform integrating soft nanoparticles with a targeting peptide and an active imaging agent for diagnostics. Biocompatible single-chain polymer nanoparticles (SCPNs) based on poly(methacrylic acid) were prepared and functionalized with the somatostatin analogue PTR86 as the targeting moiety, since somatostatin receptors are overexpressed in pancreatic cancer. The gamma emitter 67Ga was incorporated by chelation and allowed in vivo investigation of the pharmacokinetic properties of the nanoparticles using single photon emission computerized tomography (SPECT). The resulting engineered nanosystem was tested in a xenograph mouse model of human pancreatic adenocarcinoma. Imaging results demonstrate that accumulation of targeted SCPNs in the tumor is higher than that observed for nontargeted nanoparticles due to improved retention in this tissue.

Gd(III)-Dithiolane Gold Nanoparticles for T1-Weighted Magnetic Resonance Imaging of the Pancreas

Pancreatic adenocarcinoma has a 5 year survival of approximately 3% and median survival of 6 months and is among the most dismal of prognoses in all of medicine. This poor prognosis is largely due to delayed diagnosis where patients remain asymptomatic until advanced disease is present. Therefore, techniques to allow early detection of pancreatic adenocarcinoma are desperately needed. Imaging of pancreatic tissue is notoriously difficult, and the development of new imaging techniques would impact our understanding of organ physiology and pathology with applications in disease diagnosis, staging, and longitudinal response to therapy in vivo. Magnetic resonance imaging (MRI) provides numerous advantages for these types of investigations; however, it is unable to delineate the pancreas due to low inherent contrast within this tissue type. To overcome this limitation, we have prepared a new Gd(III) contrast agent that accumulates in the pancreas and provides significant contrast enhancement by MR imaging. We describe the synthesis and characterization of a new dithiolane-Gd(III) complex and a straightforward and scalable approach for conjugation to a gold nanoparticle. We present data that show the nanoconjugates exhibit very high per particle values of r1 relaxivity at both low and high magnetic field strengths due to the high Gd(III) payload. We provide evidence of pancreatic tissue labeling that includes MR images, post-mortem biodistribution analysis, and pancreatic tissue evaluation of particle localization. Significant contrast enhancement was observed allowing clear identification of the pancreas with contrast-to-noise ratios exceeding 35:1.

THE FREQUENCY OF RISK FACTORS ON TRENDS OF PANCREATIC CANCER IN KOSOVO

The aim:

The aim of this paper is to analyze different factors that influence the trends of pancreatic cancer mortality and morbidity of patients treated at the UCCK of Kosovo. Within this study, we have evaluated pancreatic cancer risk factors, durability and lethality regarding Kosovan patients who have been diagnosed and treated within Kosovo. The study in question is that of retrospective research traversing the period of 2011-2015.

Materials and methodology:

This retrospective research study includes 362 patients recently diagnosed with pancreatic cancer, 2011-2015 at the University Clinical Center of Kosovo in Pristina. The main important factors included in this study are: age, sex and risk factors that altogether have considerable influence in incidence of pancreatic cancer. The imaging diagnostics are performed with the use of 2D ECHO Phillips, MSCT Sensation 64 and 6 and 1.5T MRI Symphony Siemens that are situated in the Radiologic Clinic of UCCK. The statistic data were obtained from NIPH of Kosovo and Agency of Statistics of Kosovo.

Results:

Out of the total number of the 362 patients diagnosed with pancreatic cancer, the mortality in all age groups was higher at male patients–61.6 % of cases (n=223) with the highest number found at 51–60 years age group. The 38.4 % (n= 139) were female patients with the highest incidence frequency at F 61–70 years age group. The F/M ratio is 1:1.6. The “plane” nicotine users were found at 34 % (n=123) while the joined, nicotine/alcohol addiction was detected at 26 % (n= 94). The 18.5% (n=67) have had established diagnose of the diabetes mellitus tip II and 9.6 % (n=35) have undergone the medical treatment of the gastroduodenal peptic ulcerations. The total number of deaths is 310 (85.6%) and there are only 52 patients (14.4%) still alive. The mortality rate of the pancreatic cancer in Kosovo was 17.2 in 100.000 residents while the morbidity rate was 2.8 in 100.000 residents.

Discussion and conclusion:

This retrospective research study intends to present the role of the risk factor, that influence the mortality and morbidity of the pancreatic cancer in Kosovo and finally, to compare these results with similar studies abroad with aim to prevent the pancreatic cancer. The analyses of the obtained statistical data shows that the nicotine addiction play important role in incidence of the pancreatic cancer as well as alcohol addiction, presence of the diseases such are diabetes mellitus tip II and gastroduodenal peptic ulcers.

How Grim is Pancreatic Cancer?

Pancreatic ductal carcinoma continues to be the most lethal malignancy with rising incidence. It is the fourth most common cause of cancer death in the western world due to its low treatment success rate. In addition, because of its rapid growth and silent course, diagnosis is often only established in the advanced stages. As one of the most aggressive malignancies, the treatment of this disease is a great challenge to clinicians. This paper reviewed the natural history of pancreatic cancer, the current clinical practice and the future in pancreatic cancer management.

Pancreatic Carcinoma: the Disease that Kills

The purpose of this case report is to demonstrate the clinical symptoms and laboratory changes that have occurred very late and were very few in number even the imaging studies performed at that time showed an intensive local tumor growth associated with the wide infiltration of the both adjacent and distant upper abdominal structures. A 71-year-old male patient who was a chronic alcohol abuser and ex smoker (quit smoking 8 years earlier) presented with symptoms of mild pain on epigastric region that irradiated toward the back and significant weight loss. The initial ultrasonography (US) examination was performed, followed by the lab tests and multidetector computed tomography (MDCT) examination. The diagnostic studies confirmed the presence of the pancreatic’s body mass. The ordered laparoscopic evaluation established definitive diagnosis. Initial US examination showed heterogeneous pseudo-cystic changes and slight edema of the pancreatic parenchyma associated with the multiple oval hyperechogenic lesions of liver - the signs highly suggestive of secondary metastatic deposits. The other imaging findings that were obtained with the use of the MDCT confirmed the presence of an expansive primary process of the body of the pancreas associated with the secondary metastatic changes in liver. In addition, the consecutive lymphadenopathy was revealed along hepatoduodenal ligament, retropancreatic region and intraperitoneal compartment. Tumor markers resulted with the high values of the AFP of 2.3, CA19-9 of 423.0 U/mL, and CEA of 219.0 ng/mL. The specimen of the tumor tissue taken during laparoscopic biopsy was sent for histologic examination and the final result was “metastatic adenocarcinoma of pancreas”. Pancreatic body carcinoma has always been associated with poor prognosis because diagnosis is made at the advanced stage of the disease. Therefore, poor prognosis might be improved if early diagnosis could be made. Recent researches confirmed genetic predisposition for this disease at certain group of patients and this “high risk” group has to be followed up with regular imaging studies and lab analysis.

Molecular Imaging of Pancreatic Cancer with Antibodies

Development of novel imaging probes for cancer diagnostics remains critical for early detection of disease, yet most imaging agents are hindered by suboptimal tumor accumulation. To overcome these limitations, researchers have adapted antibodies for imaging purposes. As cancerous malignancies express atypical patterns of cell surface proteins in comparison to noncancerous tissues, novel antibody-based imaging agents can be constructed to target individual cancer cells or surrounding vasculature. Using molecular imaging techniques, these agents may be utilized for detection of malignancies and monitoring of therapeutic response. Currently, there are several imaging modalities commonly employed for molecular imaging. These imaging modalities include positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance (MR) imaging, optical imaging (fluorescence and bioluminescence), and photoacoustic (PA) imaging. While antibody-based imaging agents may be employed for a broad range of diseases, this review focuses on the molecular imaging of pancreatic cancer, as there are limited resources for imaging and treatment of pancreatic malignancies. Additionally, pancreatic cancer remains the most lethal cancer with an overall 5-year survival rate of approximately 7%, despite significant advances in the imaging and treatment of many other cancers. In this review, we discuss recent advances in molecular imaging of pancreatic cancer using antibody-based imaging agents. This task is accomplished by summarizing the current progress in each type of molecular imaging modality described above. Also, several considerations for designing and synthesizing novel antibody-based imaging agents are discussed. Lastly, the future directions of antibody-based imaging agents are discussed, emphasizing the potential applications for personalized medicine.

Magnetic resonance elastography (MRE) in cancer: Technique, analysis, and applications

Tissue mechanical properties are significantly altered with the development of cancer. Magnetic resonance elastography (MRE) is a noninvasive technique capable of quantifying tissue mechanical properties in vivo. This review describes the basic principles of MRE and introduces some of the many promising MRE methods that have been developed for the detection and characterization of cancer, evaluation of response to therapy, and investigation of the underlying mechanical mechanisms associated with malignancy.

Differential diagnosis of pancreatic cancer from other solid tumours arising from the periampullary area on MDCT

PURPOSE

To investigate CT features and differential diagnosis of pancreatic adenocarcinoma compared to other solid tumours arising in the periampullary area.

MATERIALS AND METHODS

One hundred and ninety-five patients with pathologically proven, solid periampullary tumours, including pancreatic adenocarcinoma (n = 98), neuroendocrine tumours (n = 52), gastrointestinal stromal tumours (n = 31), and solid pseudopapillary neoplasms (n = 14), underwent preoperative CT. Two radiologists reviewed CT features and rated the possibility of pancreatic adenocarcinoma.

RESULTS

Statistically common findings for pancreatic adenocarcinoma included: patient age >50 years; ill-defined margin; completely solid mass; homogeneous enhancement; hypoenhancement on arterial and venous phases; atrophy; and duct dilatation. Statistically common findings for GIST included: heterogeneous enhancement; hyperenhancement on arterial and venous phases; rim enhancement; and prominent feeding arteries. The hyperenhancement on arterial and venous phases is statistically common in NET, and heterogeneous enhancement, hypoenhancement on the arterial and venous phases are statistically common in SPN. Diagnostic performance of CT for differentiating pancreatic adenocarcinomas from other solid periampullary tumours was 0.962 and 0.977 with excellent interobserver agreement (κ = 0.824).

CONCLUSION

CT is useful not only for differentiating pancreatic adenocarcinoma form other solid tumours but also for differentiating between other solid tumours, including NET, SPN, and GIST, arising in the periampullary area.

KEY POINTS

• Periampullary tumours arise within 2 cm of major duodenal papilla. • Many mass-forming periampullary tumours can be completely removed by minimal surgery. • Accurate differentiation of pancreatic adenocarcinoma from other solid tumours is important. • CT is useful for differentiating pancreatic adenocarcinoma from other solid tumours. • CT is useful for characterization of periampullary tumours other than adenocarcinomas.

Comparison of two techniques for endoscopic ultrasonography fine-needle aspiration in solid pancreatic mass

BACKGROUND

Endoscopic ultrasonography (EUS) is a newly imagine procedure for assessment and therapeutic in option. The aims of this study are comparison two techniques about EUS-fine-needle aspiration (EUS-FNA), including successful tissue sampling, complication, procedure time, and safety.

MATERIALS AND METHODS

A total of 100 patients with pancreatic solid masses were in the study, 50 patients underwent EUS-FNA with negative pressure as Group 1 and 50 patients underwent EUS-FNA without negative pressure and stylet as Group 2 over a 36 months period.

RESULTS

The study period was from March 2011 to January 2014. In total case, the male-to-female ratio was 1.27 with a mean age of 61.7 ± 1.3 years. The involvement of different regions of the pancreas, pancreatic head had the most frequent (69%) after that uncinate (12%), body (11%) and tail (8%). In 100 pancreatic EUS-FNA samples, 48% were interpreted as malignant on pathology evaluation, 15% as suspicious for malignancy, 27% as benign processes and 10% inadequate specimen. There were no significant differences between the adequacy of sample cells in two techniques (P < 0.148).

CONCLUSION

The EUS-FNA without negative pressure and stylet technique was related with less contamination by blood and raise the diagnostic yield. We recommend further studies for better evaluation of our study with higher the cases because clinically the low the inadequate samples (6% vs. 14%) and less contamination with blood (20% vs. 50%) in the second group (P < 0.002).

Sensitivity of EUS and ERCP Endoscopic Procedures in the Detection of Pancreatic Cancer During Preoperative Staging Correlated with CT and CT Angiography Imaging Methods

The goal:

The goal of this work was to give advantage to EUS as endoscopic method in diagnosis and following therapeutic treatment of pancreatic cancer in relation to radiological methods of CT and CTA.

Material and Methods:

The study included 49 patients, 20 women and 29 men hospitalized at the Clinic for gastroenterohepatology, due to suspicion on pancreatic cancer during observed 2 years period. All cancers were histologically and cytologically confirmed. The patients underwent ERCP as a mandatory part of staging and all patients underwent endoscopic ultrasound as well as CT or CT angiography.

Results:

Testing of differences was carried out using Fisher’s exact test in open-source software R. The following characteristics were tested: involvement of the blood vessels, lymph nodes, metastases, tumor size and duodenum infiltration. Results showed statistically significant difference at the 0.05 level for EUS, CT and CT angiography. Risk ratio showed that EUS is less effective in detecting infiltration of blood vessels within a malignant process then CTA where RR=0.52, CI 0.2–1.38, p-value=0.33. EUS and CTA are equal in the diagnosis of enlarged lymph nodes affected by malignancy where RR=1.3, CI 0.75–1.42, p-value=0.09. Comparison according to distant metastases showed that EUS is less effective compared to CT in approximately 30% of cases. In the diagnosis of duodenal infiltration EUS is in 5% of cases less accurate than the CT with the RR=0.95, CI 0.27–3.32, p-value=0.76, but the CTA method is more efficient because the comparison of EUS and CTA showed RR=12.52, CI 0.2–1.38, p-value=0.33. EUS as a diagnostic method is dominant in determining the size of malignant lesions located in the pancreas as compared to CT and CTA.

Conclusion:

EUS as endoscopic method compared to CT and CTA is one of the more invasive methods of examination but due to its ability to be performed immediately, to locate a changes smaller than 5 mm and the target biopsy option, to measure the change and that in many cases determine the relationship of malignant lesions with blood vessels, along with visualization of the surrounding lymph nodes and metastases in neighboring organs, we may give this method an advantage over other methods in the preoperative staging of patients with pancreatic cancer.

The influence of linker length on the properties of cathepsin S cleavable (177)Lu-labeled HPMA copolymers for pancreatic cancer imaging

N-(2-hydroxypropyl)-methacrylamide (HPMA) copolymers have shown promise for application in the detection and staging of cancer. However, non-target accumulation, particularly in the liver and spleen, hinders the detection of resident or nearby metastatic lesions thereby decreasing diagnostic effectiveness. Our laboratory has pursued the development of cathepsin S susceptible linkers (CSLs) to reduce the non-target accumulation of diagnostic/radiotherapeutic HPMA copolymers. In this study, we ascertain if the length of the linking group impacts the cleavage and clearance kinetics, relative to each other and a non-cleavable control, due to a reduction in steric inhibition. Three different CSLs with linking groups of various lengths (0, 6 and 13 atoms) were conjugated to HPMA copolymers. In vitro cleavage studies revealed that the longest linking group (13 atoms) led to more rapid cleavage when challenged with cathepsin S. The CSL incorporated HPMA copolymers demonstrated significantly higher levels of excretion and a significant decrease in long-term hepatic and splenic retention relative to the non-cleavable control. Contrary to in vitro observations, the length of the linking group did not substantially impact the non-target in vivo clearance. In the case of HPAC tumor retention, the CSL with the null (0 atom) linker demonstrated significantly higher levels of retention relative to the other CSLs. Given these results, we find that the length of the linking group of the CSLs did not substantially impact non-target clearance, but did influence tumor retention. Overall, these results demonstrate that the CSLs can substantially improve the non-target clearance of HPMA copolymers thereby enhancing clinical potential.

Skeletal muscle metastases from pancreatic carcinoma-a case report and review of literature

With an overall mortality approaching nearly 100 %, pancreatic cancer is still a challenging disease. A major proportion of pancreatic cancers are still diagnosed at the locally advanced or metastatic stage. Tumors originating from tail region present very late due to the absence of specific symptoms and signs. The usual sites of metastases are the liver, peritoneum and lungs, with occasional reports of metastases in other sites. There are very few documented cases of gastrointestinal cancers manifesting as metastases to muscle. This is a report on a case of pancreatic cancer presenting as metastases to skeletal muscle and multiple other viscera and review of literature for pancreatic cancer metastases.

Is tumour size an underestimated feature in the current TNM system for malignancies of the pancreatic head?

BACKGROUND

As the long-term survival of pancreatic head malignancies remains dismal, efforts have been made for a better patient selection and a tailored treatment. Tumour size could also be used for patient stratification.

METHODS

One hundred and fourteen patients underwent a pancreaticoduodenectomy for pancreatic adenocarcinoma, peri-ampullary and biliary cancer stratified according to: ≤20 mm, 21-34 mm, 35-45 mm and >45 mm tumour size.

RESULTS

Patients with tumour sizes of ≤20 mm had a N1 rate of 41% and a R1/2 rate of 7%. The median survival was 3.4 years. N1 and R1/2 rates increased to 84% and 31% for tumour sizes of 21-34 mm (P = 0.0002 for N, P = 0.02 for R). The median survival decreased to 1.6 years (P = 0.0003). A further increase in tumour size of 35-45 mm revealed a further increase of N1 and R1/2 rates of 93% (P < 0.0001) and 33%, respectively. The median survival was 1.2 years (P = 0.004). Tumour sizes >45 mm were related to a further decreased median survival of 1.1 years (P = 0.2), whereas N1 and R1/2 rates were 87% and 20%, respectively.

DISCUSSION

Tumour size is an important feature of pancreatic head malignancies. A tumour diameter of 20 mm seems to be the cut-off above which an increased rate of incomplete resections and metastatic lymph nodes must be encountered and the median survival is reduced.

Increased neutrophil-lymphocyte ratio is a poor prognostic factor in patients with primary operable and inoperable pancreatic cancer

Background:

The neutrophil-lymphocyte ratio (NLR) has been proposed as an indicator of systemic inflammatory response. Previous findings from small-scale studies revealed conflicting results about its independent prognostic significance with regard to different clinical end points in pancreatic cancer (PC) patients. Therefore, the aim of our study was the external validation of the prognostic significance of NLR in a large cohort of PC patients.

Methods:

Data from 371 consecutive PC patients, treated between 2004 and 2010 at a single centre, were evaluated retrospectively. The whole cohort was stratified into two groups according to the treatment modality. Group 1 comprised 261 patients with inoperable PC at diagnosis and group 2 comprised 110 patients with surgically resected PC. Cancer-specific survival (CSS) was assessed using the Kaplan–Meier method. To evaluate the independent prognostic significance of the NLR, the modified Glasgow prognostic score (mGPS) and the platelet-lymphocyte ratio univariate and multivariate Cox regression models were applied.

Results:

Multivariate analysis identified increased NLR as an independent prognostic factor for inoperable PC patients (hazard ratio (HR)=2.53, confidence interval (CI)=1.64–3.91, P<0.001) and surgically resected PC patients (HR=1.61, CI=1.02–2.53, P=0.039). In inoperable PC patients, the mGPS was associated with poor CSS only in univariate analysis (HR=1.44, CI=1.04–1.98).

Conclusion:

Risk prediction for cancer-related end points using NLR does add independent prognostic information to other well-established prognostic factors in patients with PC, regardless of the undergoing therapeutic modality. Thus, the NLR should be considered for future individual risk assessment in patients with PC.