Three-dimensional linear endoscopic ultrasound-feasibility of a novel technique applied for the detection of vessel involvement of pancreatic masses

Diagnostic Endoscopic Ultrasound in Pancreatology: Focus on Normal Variants and Pancreatic Masses

Background

Endoscopic ultrasound (EUS) is a main tool in gastroenterology for both diagnosis and exclusion of pancreatic pathology. It allows minimally invasive assessment of various diseases or anatomic variations affecting the pancreas also with the help of new Doppler technologies, elastography, contrast-enhanced imaging including post hoc image processing with quantification analyses, three-dimensional reconstruction, and artificial intelligence. EUS also allows interventional direct access to the pancreatic parenchyma and the retroperitoneal space, to the pancreatic duct, pancreatic masses, cysts, and vascular structures.

Summary

This review aimed to summarize new developments of EUS in the field of pancreatology. We highlight the role of EUS in evaluating pancreatic pathology by describing normal anatomic variants like pancreas divisum, pancreatic lipomatosis, pancreatic fibrosis in the elderly and characterizing pancreatic masses, both in the context of chronic pancreatitis and within healthy pancreatic parenchyma. EUS is considered the optimal imaging modality for pancreatic masses of uncertain dignity and allows both cytological diagnosis and histology, which is essential not only for neoplastic conditions but also for tailoring therapy for benign inflammatory conditions.

Key Messages

EUS plays an indispensable role in pancreatology and the development of new diagnostic and interventional approaches to the retroperitoneal space and the pancreas exponentially increased over the last years. The development of computer-aided diagnosis and artificial intelligence algorithms hold the potential to overcome the obstacles associated with interobserver variability and will most likely support decision-making in the management of pancreatic disease.

Three-Dimensional Printing and Its Potential to Develop Sensors for Cancer with Improved Performance

Cancer is the second leading cause of death globally and early diagnosis is the best strategy to reduce mortality risk. Biosensors to detect cancer biomarkers are based on various principles of detection, including electrochemical, optical, electrical, and mechanical measurements. Despite the advances in the identification of biomarkers and the conventional 2D manufacturing processes, detection methods for cancers still require improvements in terms of selectivity and sensitivity, especially for point-of-care diagnosis. Three-dimensional printing may offer the features to produce complex geometries in the design of high-precision, low-cost sensors. Three-dimensional printing, also known as additive manufacturing, allows for the production of sensitive, user-friendly, and semi-automated sensors, whose composition, geometry, and functionality can be controlled. This paper reviews the recent use of 3D printing in biosensors for cancer diagnosis, highlighting the main advantages and advances achieved with this technology. Additionally, the challenges in 3D printing technology for the mass production of high-performance biosensors for cancer diagnosis are addressed.

Advanced Imaging of the Biliary System and Pancreas

Despite advances in noninvasive techniques for imaging the pancreaticobiliary system, several disease processes including indeterminate biliary strictures as well as neuroendocrine tumors, inflammatory pseudotumors, and complex cysts of the pancreas remain difficult to characterize. New endoscopic imaging technologies have emerged to address these challenges. Cholangioscopy and intraductal ultrasound (IDUS) are powerful tools to characterize subtle biliary concretions and strictures. Confocal Laser Endomicroscopy (CLE) and Optical Coherence Tomography (OCT) are emerging approaches for the most difficult biliary lesions. Contrast harmonic endoscopic ultrasound (CH-EUS), elastography, and 3D-EUS are improving the approach to subtle pancreatic lesions, particularly in the context of indeterminate tissue sampling. Pancreatoscopy, pancreatic IDUS, and intracystic CLE hold promise to further improve the assessment of pancreatic cysts. We aim to comprehensively review the emerging clinical evidence for these innovative endoscopic imaging techniques.

Impact of endoscopic ultrasonography on diagnosis of pancreatic cancer

Accumulated evidence has revealed that endoscopic ultrasonography (EUS) has had a great impact on the clinical evaluation of pancreatic cancers. EUS can provide high-resolution images of the pancreas with a quality regarded as far surpassing that achieved on transabdominal ultrasound (US), computed tomography (CT), or magnetic resonance imaging (MRI). EUS is particularly useful for the detection of small pancreatic lesions, while EUS and its related techniques such as contrast-enhanced EUS (CE-EUS), EUS elastography, and EUS-guided fine needle aspiration (EUS-FNA) are also useful in the differential diagnosis of solid or cystic pancreatic lesions and the staging (T-staging, N-staging, and M-staging) of pancreatic cancers. In the diagnosis of pancreatic lesions, CE-EUS and EUS elastography play a complementary role to conventional EUS. When sampling is performed using EUS-FNA, CE-EUS and EUS elastography provide information on the target lesions. Thus, conventional EUS, CE-EUS, EUS elastography, and EUS-FNA are essential in the clinical investigation of pancreatic cancer.

A novel fusion imaging system for endoscopic ultrasound

Background and Objective:

Navigation of a flexible endoscopic ultrasound (EUS) probe inside the gastrointestinal (GI) tract is problematic due to the small window size and complex anatomy. The goal of the present study was to test the feasibility of a novel fusion imaging (FI) system which uses electromagnetic (EM) sensors to co-register the live EUS images with the pre-procedure computed tomography (CT) data with a novel navigation algorithm and catheter.

Methods:

An experienced gastroenterologist and a novice EUS operator tested the FI system on a GI tract bench top model. Also, the experienced gastroenterologist performed a case series of 20 patients during routine EUS examinations.

Results:

On the bench top model, the experienced and novice doctors reached the targets in 67 ± 18 s and 150 ± 24 s with a registration error of 6 ± 3 mm and 11 ± 4 mm, respectively. In the case series, the total procedure time was 24.6 ± 6.6 min, while the time to reach the clinical target was 8.7 ± 4.2 min.

Conclusions:

The FI system is feasible for clinical use, and can reduce the learning curve for EUS procedures and improve navigation and targeting in difficult anatomic locations.

The role of contrast-enhanced endoscopic ultrasound in pancreatic adenocarcinoma

Contrast-enhanced endoscopic ultrasound (CE-EUS) allows characterization, differentiation, and staging of focal pancreatic masses. The method has a high sensitivity and specificity for the diagnosis of pancreatic adenocarcinoma which is visualized as hypo-enhanced as compared to the rest of the parenchyma while chronic pancreatitis and neuroendocrine tumors are generally either iso-enhanced or hyper-enhanced. The development of contrast-enhanced low mechanical index harmonic imaging techniques used in real time during endoscopic ultrasound (EUS) allowed perfusion imaging and the quantification of intensity of the contrast signal through time-intensity curve analysis. Thus, contrast harmonic imaging-EUS has been used to differentiate pancreatic adenocarcinoma based on lower values of the peak enhancement. Future applications of CE-EUS in pancreatic adenocarcinoma include not only use of targeted contrast agents for early detection, tridimensional and fusion techniques for enhanced staging and resectability assessment but also novel applications of perfusion imaging for monitoring ablative therapy, improved local detection through EUS-guided sampling of portal vein flow or enhanced drug delivery through sonoporation and ultrasound-induced release of the drugs locally.

Diagnostic accuracy of EUS and CT of vascular invasion in pancreatic cancer: a systematic review

OBJECTIVE

The objective of this study was to summarize the accuracy of preoperative vascular invasion with endoscopic ultrasound (EUS) and computed tomography (CT) test performance in pancreatic cancer with meta-analysis

METHOD

Two reviewers searched MEDLINE database to identify relevant studies. The reference lists of the trials were manually searched. Included studies used surgical and/or histological findings as the "gold standard," and provided sufficient data to construct a diagnostic 2 × 2 table. A statistical program of Meta-Disc was used to calculate the pooled sensitivity, specificity, positive LR, negative LR, DOR, and the SROC curve. Publication bias was assessed by Deeks' asymmetry test. Sensitivity analysis and subgroup analysis were calculated to down the heterogeneity. Meta-regression was calculated to evaluate potential sources of heterogeneity

RESULT

A total of 30 studies with 1,554 patients were included for the analysis, nine of these studies compared EUS with CT to assess the diagnostic efficiency The pooled sensitivity of EUS and CT was 72 % (95 % CI 67-77 %) and 63 % (95 % CI 58-67 %), and the pooled specificity of EUS and CT was 89 % (95 % CI 86-92 %) and 92 % (95 % CI 90-94 %), respectively. The positive LR of EUS and CT was 5.14 (95 % CI 3.14-8.40) and 6.21 (95 % CI 3.96-9.71), and the negative LR was 0.36 (95 % CI 0.25-0.52) and 0.41 (95 % CI 0.31-0.55), respectively. The AUCs of EUS and CT were 0.9037 and 0.8948. The subgroup analysis of nine studies performed both EUS and CT showed CT scan with a lower sensitivity of 48 % (95 % CI 0.40-0.56), when compared to EUS of 69 % (95 % CI 0.61-0.77). The overall AUCs of CT scan appear to be lower (AUCs = 0.8589), compared with EUS (AUCs = 0.9379) CONCLUSION: EUS performed better than CT in differentiating vascular invasion preoperative on pancreatic cancer. EUS could provide other additional information when compared with CT.

Promising outcomes of screening for pancreatic cancer by genetic testing and endoscopic ultrasound

OBJECTIVE

This study aimed to determine if screening patients based on certain cancer syndromes or family history criteria can lead to early detection of pancreatic cancer.

METHODS

This was a cohort study from 2008 to 2011 at a large tertiary referral center. A total of 30 patients met high-risk criteria after genetic counseling and were referred to a gastroenterologist for possible endoscopic ultrasound (EUS).

RESULTS

Of the 30 patients, 16 underwent EUS. Subsequently, 3 patients had fine needle aspiration. Two patients had pancreatic adenocarcinoma, and 1 patient had an intraductal papillary mucinous neoplasm with low-grade dysplasia. The 2 patients with pancreatic adenocarcinoma both had breast cancer and BRCA2 mutations. The patient with the intraductal papillary mucinous neoplasm had Peutz-Jeghers syndrome. All 3 patients underwent surgery and have remained cancer free.

CONCLUSIONS

Genetic risk assessment with EUS +/- fine needle aspiration in high-risk patients may lead to earlier detection of pancreatic cancer and potentially improve overall morbidity and mortality. Greater emphasis should be placed on screening patients for hereditary cancer syndromes that increase the risk of pancreatic cancer.

Impact of rapid on-site evaluation on the adequacy of endoscopic-ultrasound guided fine-needle aspiration of solid pancreatic lesions: a systematic review and meta-analysis

BACKGROUND

Rapid on-site evaluation (ROSE) has the potential to improve adequacy rates for endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of solid pancreatic lesions, but its impact is context-dependent. No studies exist that summarize the relationship between ROSE, number of needle passes, and resulting adequacy rates.

AIMS

To analyze data from previous studies to establish if ROSE is associated with improved adequacy rates; to evaluate the relationship between ROSE, number of needle passes, and the resulting adequacy rates of EUS-FNA for solid pancreatic lesions.

METHODS

Systematic review and meta-analysis of studies reporting the adequacy rates for EUS-FNA of solid pancreatic lesions.

RESULTS

The search produced 3822 original studies, of which 70 studies met our inclusion criteria. The overall average adequacy rate was 96.2% (95% confidence interval: 95.5, 96.9). ROSE was associated with a statistically significant improvement of up to 3.5% in adequacy rates. There was heterogeneity in adequacy rates across all subgroups. No association between the assessor type and adequacy rates was found. Studies with ROSE have high per-case adequacy and a relatively high number of needle passes in contrast to non-ROSE studies. ROSE is an effect modifier of the relationship between number of needle passes and adequacy.

CONCLUSIONS

ROSE is associated with up to 3.5% improvement in adequacy rates for EUS-FNA of solid pancreatic lesions. ROSE assessor type has no impact on adequacy rates. ROSE is an effect modifier on the relationship between needle passes and per-case adequacy for EUS-FNA of solid pancreatic lesions.

Performance characteristics of endoscopic ultrasound in the staging of pancreatic cancer: a meta-analysis

CONTEXT

The optimal approach to pre-operative imaging assessment of pancreatic cancer is unknown.

OBJECTIVE

The aim of this meta-analysis was to assess accuracy and performance characteristics of EUS in determining nodal staging, vascular invasion, and prediction of resectability of pancreatic cancer. A secondary aim was to perform head to head comparison of performance characteristics between EUS and CT for nodal staging, vascular invasion and resectability.

DESIGN

Data from EUS studies were pooled according to bivariate generalized random effects model. Pooled estimates for CT were obtained from studies which performed head to head comparison between EUS and CT.

PATIENTS

Patients with pancreatic cancer undergoing pre-operative imaging assessment.

INTERVENTION

EUS.

MAIN OUTCOME MEASURE

Pooled sensitivity, specificity, positive and negative predictive values of EUS for nodal staging, vascular invasion and resectability.

RESULTS

Forty-nine studies were considered of which 29 met inclusion criteria with a total of 1,330 patients. Pooled summary estimates for EUS-nodal staging were 69% for sensitivity and 81% for specificity. For vascular invasion, sensitivity was 85% and specificity was 91%. The sensitivity and specificity for resectability was 90% and 86%, respectively. CT scan showed lower sensitivity than EUS for nodal staging (24% vs. 58%) and vascular invasion (58% vs. 86%); however, the specificities for nodal staging (88% vs. 85%) and vascular invasion (95% vs. 93%) were comparable in studies where both imaging techniques were performed. The sensitivity and specificity of CT in determining resectability (90% and 69%) was similar to that of EUS (87% and 89%).

CONCLUSIONS

EUS is an accurate pre-operative tool in the assessment of nodal staging, vascular invasion and resectability in patients with pancreatic cancer.

Advanced EUS imaging for early detection of pancreatic cancer

Endoscopic ultrasound (EUS)-fine needle aspiration remains the gold standard for diagnosing pancreatic malignancy. However, in a subset of patients, limitations remain in regards to image quality and diagnostic yield of biopsies. Several new devices and processors have been developed that allow for enhancement of the EUS image. Initial studies of these modalities do show promise. However, cost, availability, and overall incremental benefit to EUS-fine needle aspiration have yet to be determined.

Standards of the Polish Ultrasound Society - update. Pancreas examination

Ultrasound examination of the pancreas constitutes an integral part of the abdominal ultrasound. It is mostly indicated to diagnose pain in the epigastrium, discomfort and jaundice as well as to monitor the patients with acute pancreatitis. The assessment of this organ in an ultrasound examination may be problematic due to its anatomical location and the fact that it might be covered by gastric and duodenal contents as well as due to a number of possible pathological changes, including inflammation and benign or malignant neoplasms, which require differentiation. The basis for establishing a correct diagnosis is the knowledge of the examination technique, correct pancreas structure and images of individual pathologies. This paper presents the standards of ultrasound examination published in 2011 and updated with the current knowledge. The following are discussed: preparation of the patient for the examination, abnormal lesions in the pancreas, acute pancreatitis, chronic pancreatitis, cystic lesions (benign and malignant cysts) and solid focal lesions. Ultrasound is also used to guide the drainage of fluid cisterns, abscesses and cysts. The prime role in the diagnosis and treatment of selected diseases of the upper gastrointestinal tract and parenchymal organs of the abdomen belongs to endosonography of the upper gastrointestinal tract, with the possibility to conduct a fine needle aspiration biopsy, and intraoperative or laparoscopic ultrasound.

A novel three-dimensional endoscopic ultrasound technique for the freehand examination of the oesophagus

This study details the development and evaluation of a freehand radial three-dimensional endoscopic ultrasound (3D-EUS) technique for use in the upper gastro-intestinal tract. It comprised of a commercial EUS system, a custom acquisition system to simultaneous acquire radial B-mode images and corresponding incremental changes in position of the scope as it was withdrawn and a custom 3D-EUS package written in Matlab™, to reconstruct and analyse the volume. This technique was evaluated using an EUS phantom with embedded objects of known dimensions and volumes and with clinical images acquired during routine cancer staging. For the phantom measurements, average Z-dimensional error was <1% and volume errors were 1.4% (volume(1) = 48930 mm(3)) and 4.5% (volume(2) = 5100 mm(3)). Application of this technique to EUS acquired clinical images produced excellent characterisation of oesophageal structures and accurate dimension and volume measurements. It also enabled the endoscopist to review "off-line" the EUS examination in case important information was missed.

Endosonography in solid and cystic pancreatic tumors

Pancreatic tumors being either benign or malignant can be solid or cystic. Although diverse in presentation, their imaging features share commonalities and it is often difficult to distinguish these tumors. Endoscopic ultrasonography (EUS) is the most sensitive of the imaging procedures currently available for characterizing pancreatic tumors, and is especially good in identifying the smaller sized tumors. Additional applications inclusive of EUS-guided fine needle aspiration (EUS-FNA) are useful in tissue sampling and preoperative staging of pancreatic tumors.Although diagnostic capabilities have greatly evolved with advances in EUS and tissue processing technology (cytology, tumor markers, DNA analysis), differentiation of benign and malignant neoplasms, neoplastic and non-neoplastic (chronic pancreatitis) conditions, continues to be challenging.Recent innovative applications include contrast-enhanced EUS with Doppler mode, contrast-enhanced harmonic EUS, 3-dimensinal EUS, and EUS elastography. Incorporation of these methods has improved the differential diagnosis of pancreatic tumors. Finally, a multi-disciplinary approach involving radiology, gastroenterology and surgical specialties is often necessary for accurate diagnosis and management of solid and cystic pancreatic tumors.

The role of linear array EUS for diagnosis of pancreatic malignancies in the current situation

Over the last few decades, the role of endoscopic ultrasound (EUS) in the diagnosis of pancreatic malignancies has greatly increased by allowing earlier diagnosis and appropriate staging. The development of linear array EUS also allows fine needle aspiration (FNA) to be carried out under real-time EUS guidance and offers definitive diagnosis, which has fundamentally changed the diagnostic approach to pancreatic malignancies. Moreover, linear array EUS with the EUS-FNA technique has a therapeutic application that has expanded the role of this procedure in the management of pancreatic malignancies. This review will focus on the features of linear array EUS and discuss the current role of linear array EUS in the diagnosis of pancreatic malignancies.

Endoscopic ultrasound in the papilla and the periampullary region

Endoscopic ultrasound (EUS) provides relevant information when an ampullary or periampullary tumor is suspected. Early detection, T and N staging and Fine Needle Aspiration plus cithologic confirmation, are some of the expected benefits. Exclusion of benign findings like choledocholithiasis or chronic pancreatitis is also important. A correct understanding of the complex ampullary and periampullary anatomy is needed. Knowledge of the individual clinical history and other previous diagnostic images all contribute to a successful EUS examination. Radial and lineal EUS images are uniquely detailed and, at the moment, it seems to be the best way to exclude or confirm malignant or benign findings. We propose a procedural algorithm, including EUS, for suspected ampullary or periampullary tumors. This review summarizes the vast amount of information to be found spread in the literature, and recognizes this small anatomic area as the origin for a clinical entity with proper clinical presentation, proper imaging and proper therapeutic resolutions. The benefits of performing EUS for its study are highlighted.

Is there still a role for laparoscopy combined with laparoscopic ultrasonography in the staging of pancreatic cancer?

PURPOSE

This study was designed to compare our laparoscopic ultrasonography (LUS) experience in the resectability evaluation of pancreatic or periampullary cancers (PAC) in two different periods: before and after the introduction of multidetector CT (MDCT).

METHODS

We prospectively enrolled 104 CT-resectable patients with PAC. During Step 1 (1995-1999), we performed LUS on all patients, whereas during Step 2 (2002-2007), LUS was performed selectively according to Pisters' criteria.

RESULTS

LUS was satisfactorily performed in all cases. At Step 1 accuracy of LUS in predicting pancreatic resectability was high (96%) but it was markedly lower in a subgroup of patients with close contact between tumor and portal vein (sensibility of 57%). At Step 2, selective LUS was performed on 9 of 64 patients (14%). LUS confirmed the MDCT finding of unresectability in 8 of 9 cases, and allowed curative resection in 1 case. Only 1 of 55 of the patients who did not undergo LUS would have benefited from the procedure. The yield of LUS decreased from 45% before to 1.8% after MDCT.

CONCLUSIONS

In resectable-MDCT patients, routine LUS is unjustified. However, in doubtful MDCT cases, LUS has yet a good yield. In the event of close vascular contact, neither MDCT nor LUS seem to be conclusive, and laparotomy is still the only solution.

Three-dimensional ultrasound imaging

This review is about the development of three-dimensional (3D) ultrasonic medical imaging, how it works, and where its future lies. It assumes knowledge of two-dimensional (2D) ultrasound, which is covered elsewhere in this issue. The three main ways in which 3D ultrasound may be acquired are described: the mechanically swept 3D probe, the 2D transducer array that can acquire intrinsically 3D data, and the freehand 3D ultrasound. This provides an appreciation of the constraints implicit in each of these approaches together with their strengths and weaknesses. Then some of the techniques that are used for processing the 3D data and the way this can lead to information of clinical value are discussed. A table is provided to show the range of clinical applications reported in the literature. Finally, the discussion relating to the technology and its clinical applications to explain why 3D ultrasound has been relatively slow to be adopted in routine clinics is drawn together and the issues that will govern its development in the future explored.

Vascular invasion in pancreatic cancer: Imaging modalities, preoperative diagnosis and surgical management

Pancreatic cancer is associated with a poor prognosis, and surgical resection remains the only chance for curative therapy. In the absence of metastatic disease, which would preclude resection, assessment of vascular invasion is an important parameter for determining resectability of pancreatic cancer. A frequent error is to misdiagnose an involved major vessel. Obviously, surgical exploration with pathological examination remains the “gold standard” in terms of evaluation of resectability, especially from the point of view of vascular involvement. However, current imaging modalities have improved and allow detection of vascular invasion with more accuracy. A venous resection in pancreatic cancer is a feasible technique and relatively reliable. Nevertheless, a survival benefit is not achieved by curative resection in patients with pancreatic cancer and vascular invasion. Although the discovery of an arterial invasion during the operation might require an aggressive management, discovery before the operation should be considered as a contraindication. Detection of vascular invasion remains one of the most important challenges in pancreatic surgery. The aim of this article is to provide a complete review of the different imaging modalities in the detection of vascular invasion in pancreatic cancer.

A prospective diagnostic accuracy study of 18F-fluorodeoxyglucose positron emission tomography/computed tomography, multidetector row computed tomography, and magnetic resonance imaging in primary diagnosis and staging of pancreatic cancer

OBJECTIVE

To prospectively compare the accuracy of combined positron emission tomography/computed tomography using F-fluorodeoxyglucose (FDG-PET/CT), multidetector row computed tomography (MDCT), and magnetic resonance imaging (MRI) in the evaluation of patients with suspected pancreatic malignancy.

SUMMARY BACKGROUND DATA

FDG-PET/CT imaging is increasingly used for staging of pancreatic cancer. Preliminary data suggest a significant influence of FDG-PET/CT on treatment planning, although its role is still evolving.

METHODS

Thirty-eight consecutive patients with suspicion of pancreatic malignancy were enrolled. Patients underwent a protocol including FDG-PET/CT, MDCT, and MRI combined with magnetic resonance cholangiopancreatography, all of which were blindly evaluated. The findings were confirmed macroscopically at operation and/or by histopathologic analysis (n = 29) or follow-up (n = 9). Results of TNM classification of different imaging methods were compared with clinical TNM classification.

RESULTS

Pancreatic adenocarcinoma was diagnosed in 17 patients, neuroendocrine tumor in 3, mass-forming pancreatitis in 4, cystic lesion in 6, and fibrosis in 2. Six patients had a finding of a normal pancreas. The diagnostic accuracy of FDG-PET/CT for pancreatic malignancy was 89%, compared with 76% and 79% for MDCT and MRI, respectively. In the differential diagnosis of suspected malignant biliary stricture at endoscopic retrograde cholangiopancreaticography (n = 21), FDG-PET/CT had a positive predictive value of 92%. In 17 patients with advanced pancreatic adenocarcinoma, FDG-PET/CT had a sensitivity of 30% for N- and 88% for M-staging. Both MDCT and MRI had sensitivities of 30% for N- and 38% for M-staging. Furthermore, the clinical management of 10 patients (26%) was altered after FDG-PET/CT.

CONCLUSION

FDG-PET/CT was more sensitive than conventional imaging in the diagnosis of both primary pancreatic adenocarcinoma and associated distant metastases. In contrast, the sensitivity of FDG-PET/CT was poor in detecting local lymph node metastasis, which would have been important for an assessment of resectability. We recommend the use of FDG-PET/CT in the evaluation of diagnostically challenging cases, especially in patients with biliary strictures without evidence of malignancy in conventional imaging.

Does portal-superior mesenteric vein invasion still indicate irresectability for pancreatic carcinoma?

BACKGROUND

Pancreatic carcinoma frequently infiltrates the portal vein or the superior mesenteric vein; pancreatectomy combined with portal vein/superior mesenteric vein resection represents a potentially curative treatment in these cases but is still a controversial procedure.

METHODS

After performing a computerized Medline search, 12 series published during the last 8 years were selected, enrolling 399 patients who underwent pancreatectomy combined with portal vein/superior mesenteric vein resection for pancreatic carcinoma. Data were examined for information about indications, operation, adjuvant therapies, histopathology of resected specimens, perioperative results, and survival. Also, previous literature regarding the issue was extensively reviewed.

RESULTS

Operative mortality and postoperative complication rates ranged from 0 to 7.7% and 16.7% to 54%, respectively. Median survival varied from 13 to 22 months; 5-year survival rate ranged from 9% to 18%.

CONCLUSIONS

The current literature suggests that portal vein/superior mesenteric vein resection combined with pancreatectomy is a safe and feasible procedure that increases the number of patients who undergo curative resection and, therefore, provides important survival benefits to selected groups of patients. This procedure should always be considered in case of suspected tumor infiltration of portal/superior mesenteric vein to achieve clear resection margins, in the absence of other contraindications for resection.

Role of endoscopic ultrasound in the diagnosis and staging of pancreatic cancer

Early diagnosis of pancreatic cancer remains a difficult task, and multiple imaging tests have been proposed over the years. The aim of this review is to describe the current role of endoscopic ultrasound (EUS) for the diagnosis and staging of patients with pancreatic cancer. A detailed search of MEDLINE between 1980 and 2007 was performed using the following keywords: pancreatic cancer, endoscopic ultrasound, diagnosis, and staging. References of the selected articles were also browsed and consulted. Despite progress made with other imaging methods, EUS is still considered to be superior for the detection of clinically suspected lesions, especially if the results of other cross-sectional imaging modalities are equivocal. The major advantage of EUS is the high negative predictive value that approaches 100%, indicating that the absence of a focal mass reliably excludes pancreatic cancer. The introduction of EUS-guided fine needle aspiration allows a preoperative diagnosis in patients with resectable cancer, as well as a confirmation of diagnosis before chemoradiotherapy for those that are not. This comprehensive review highlighted the diagnostic capabilities of EUS including the newest refinements such as contrast-enhanced EUS, EUS elastography, and 3-dimensional EUS. The place of EUS-guided biopsy is also emphasized, including the addition of molecular marker techniques.

Diagnostic accuracy of EUS for vascular invasion in pancreatic and periampullary cancers: a meta-analysis and systematic review

BACKGROUND

Vascular invasion (VI) in a patient with pancreatic or periampullary cancers precludes surgery and indicates a poor prognosis. Published data on the accuracy of EUS in diagnosing VI is varied.

OBJECTIVE

The aim of this meta-analysis was to evaluate the accuracy of EUS in diagnosing VI in patients with pancreatic and periampullary cancers.

DESIGN

Data from EUS studies were pooled according to the Mantel-Haenszel and DerSimonian Laird methods.

PATIENTS

EUS studies in which VI was confirmed by surgery or angiography were selected.

INTERVENTIONS

EUS.

MAIN OUTCOME MEASURES

Pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio of EUS.

RESULTS

Data were extracted from 29 studies (N = 1308) that met the inclusion criteria. The pooled sensitivity of EUS in diagnosing VI was 73% (95% CI, 68.8-76.9) and the pooled specificity was 90.2% (95% CI, 87.9-92.2). The positive likelihood ratio for diagnosing VI by EUS was 9.1 (95% CI, 4.6-17.9) and the negative likelihood ratio was 0.3 (95% CI, 0.2-0.5). Diagnostic odds ratio, the odds of having VI in positive as compared with negative EUS studies, was 40.1 (95% CI, 16.1-99.9). The P value for chi(2) heterogeneity for all the pooled estimates was >.05.

CONCLUSIONS

Although EUS is the best noninvasive test to diagnose VI in pancreatic and periampullary cancers, this meta-analysis showed that the specificity (90%) is high but the sensitivity (73%) is not as high as suggested. Further refinements in EUS technologies and interpretation may improve the sensitivity for detecting VI.

New advances in pancreatic imaging

PURPOSE OF REVIEW

This review serves to highlight new technology and novel applications of existing techniques and their role in the management of pancreatic diseases, including acute and chronic pancreatitis, pancreatic cancer, and pancreatic cystic neoplasms.

RECENT FINDINGS

Contrast-enhanced ultrasound has shown promise in evaluating the severity of acute pancreatitis, staging pancreatic cancer, and predicting malignancy in cystic neoplasms. Optical coherence tomography within the pancreatic duct appears to be able to differentiate malignant and normal pancreatic ducts. Spectroscopy may prove useful in differentiating focal chronic pancreatitis from malignancy. Multidetector-row computed tomography may provide more accurate information regarding cancer respectability and differentiation between ductal type of intraductal papillary mucinous tumors.

SUMMARY

These new developments will help with the diagnosis and staging of pancreatic diseases.