Prospective evaluation of pancreatic tumors: accuracy of MR imaging with MR cholangiopancreatography and MR angiography

Optimal value of CA19-9 determined by KRAS-mutated circulating tumor DNA contributes to the prediction of prognosis in pancreatic cancer patients

Despite the acceptance of carbohydrate antigen 19-9 (CA19-9) as a valuable predictor for the prognosis of pancreatic ductal adenocarcinoma (PDAC), its cutoff value remains controversial. Our previous study showed a significant correlation between CA19-9 levels and the presence of KRAS-mutated ctDNA in the blood of patients with PDAC. Based on this correlation, we investigated the optimal cutoff value of CA19-9 before surgery. Continuous CA19-9 values and KRAS-mutated ctDNAs were monitored in 22 patients with unresectable PDAC who underwent chemotherapy between 2015 and 2017. Receiver operating characteristic curve analysis identified 949.7 U/mL of CA19-9 as the cutoff value corresponding to the presence of KRAS-mutated ctDNA. The median value of CA19-9 was 221.1 U/mL. Subsequently, these values were verified for their prognostic values of recurrence-free survival (RFS) and overall survival (OS) in 60 patients who underwent surgery between 2005 and 2013. Multivariate analysis revealed that 949.7 U/mL of CA19-9 was an independent risk factor for OS and RFS in these patients (P = 0.001 and P = 0.010, respectively), along with lymph node metastasis (P = 0.008 and P = 0.017), unlike the median CA19-9 level (P = 0.150 and P = 0.210). The optimal CA19-9 level contributes to the prediction of prognosis in patients with PDAC before surgery.

Current controversies and advances in the management of pancreatic adenocarcinoma

Pancreatic adenocarcinoma is a lethal disease with a mortality rate that has not significantly improved over decades. This is likely due to several challenges unique to pancreatic cancer. Most patients with pancreatic cancer are diagnosed at a late stage of disease due to the lack of specific symptoms prompting an early investigation. A small subset of patients who are diagnosed at an early stage have a better chance at survival with curative surgical resection, but most patients still succumb to the disease in a few years. The dismal overall prognosis is due to suspected micro-metastasis at an early stage. Due to this reason, there is a recent interest in treating all patients with pancreatic cancers with systemic therapy upfront (including the ones that are surgically resectable). This approach is still not the standard of care due to the lack of robust prospective data available. Recent advancements in treatment regimens of chemotherapy, radiation and immunotherapy have improved the overall short-term survival but the long-term survival still remains poor. Novel approaches in diagnosis and treatment have shown promise in clinical studies but long-term clinical data is lacking. The following manuscript presents an overview of the epidemiology, diagnosis, staging, recent advances, novel approaches and controversies in the management of pancreatic adenocarcinoma.

Magnetic resonance imaging for preoperative staging of pancreatic cancer based on the 8th edition of AJCC guidelines

Background

Preoperative staging of pancreatic cancer determines the choice of treatment. Magnetic resonance imaging (MRI) plays an important role in preoperative staging of pancreatic cancer. The American Joint Committee on Cancer (AJCC) TNM staging system was revised to its 8^th version in 2016, there has been no report correlating the 8^th edition of the AJCC TNM staging with preoperative MRI examinations and pathological findings. The purpose of our study is to determine the staging accuracy and evaluate the resectability by using MRI about pancreatic cancer compared with intraoperative or pathological findings according to the 8^th edition of the AJCC TNM staging system.

Methods

One hundred thirty-two patients with a pathological diagnosis of pancreatic cancer who underwent preoperative MRI were identified. The clinical data, MRI findings and pathological findings were analyzed. Preoperative MRI staging and resectability evaluation were compared with pathological findings. The accuracy of MRI for preoperative T and N staging was evaluated, and the sensitivity, specificity and accuracy of MRI in evaluating the resectability were assessed. All the staging and resectability assessments were according to the 8^th edition of the AJCC TNM staging system.

Results

Analysis showed that the accuracy of MRI for evaluation of the T and N stages was 82.6% (109/132) and 74.2% (98/132), respectively. The sensitivity and specificity of MRI in assessing the resectability were 94.2% and 71.4%, respectively. Integrating the 8^th edition of the AJCC TNM stage, no significant differences were identified between the preoperative MRI and pathological results for the staging of pancreatic cancer (P=0.805).

Conclusions

MRI is highly accurate for T staging and moderately accurate for N staging. MRI provides important preoperative evaluation of the stage and resectability of pancreatic cancer based on the 8^th edition of the AJCC TNM staging system.

Diffusion-weighted image improves detectability of magnetic resonance cholangiopancreatography for pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasm

The present study is aimed to clarify the utility of magnetic resonance cholangiopancreatography (MRCP) and the additional value of diffusion-weighted imaging (DWI) in diagnosing pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN).This retrospective study involved 38 patients with PDAC concomitant with IPMN and 114 patients (control) who were randomly selected from 320 patients with IPMN without PDAC and were matched with cases for magnetic resonance imaging (MRI) strength (1.5 T/3.0 T). Two radiologists reviewed the 2 MR image sets with relevant clinical information blinded, first MRCP alone and then combined MRI set including DWI. Diagnostic capability and interobserver agreement were assessed by using receiver operating characteristics curve (Az) analysis and weighted κ statistics.Az values for the 2 observers were 0.834 and 0.821 for MRCP alone and 0.964 and 0.926 for the combined MRI (P < .001 and P < .001), respectively. The sensitivity of MRCP alone was 61% (23/38), with both observers failing to diagnose PDACs located at the end of tail or away from the pancreatic duct. Meanwhile, with combined MRI, sensitivity was significantly increased for both observers (61% to 92%, P = .002; 61% to 87%, P = .004). Moreover, the interobserver agreement was higher with combined MRI (κ = 0.85) than MRCP alone (κ = 0.59).MRCP and DWI might be a superior option with a higher diagnostic capability of PDAC concomitant with IPMN than MRCP alone, especially for tumors away from the pancreatic duct.

Establishment and Verification of a Scoring Model for the Differential Diagnosis of Pancreatic Cancer and Chronic Pancreatitis

OBJECTIVES

The aims of this study were to establish a scoring model for the differential diagnosis of pancreatic cancer (PC) and chronic pancreatitis (CP) and to evaluate its diagnostic efficacy.

METHODS

The data of 502 patients with PC and 210 patients with CP at the Peking Union Medical College Hospital from January 1999 to December 2013 were retrospectively analyzed. Binary logistic regression was applied to establish the prediction model for the differential diagnosis. The model was verified using the method of leave-one-out cross-validation.

RESULTS

The scoring system was established with 5 variables including age, carbohydrate antigen 19-9 level, splenic vein invasion, irregular dilatation of the pancreatic duct, and nontruncated pancreatic duct stenosis. The score range was from -2 to 3. The area under the receiver operating characteristic curve of the objects was 0.779 (95% confidence interval, 0.744-0.814) (P < 0.01), indicating that the scoring system is good at differentiation of PC with CP. With a score of 1 as the diagnostic cut-off value, the diagnostic sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rate were 71.3%, 69.0%, 70.0%, 71.4%, and 70.2%, respectively.

CONCLUSIONS

The scoring model may improve the differential diagnosis of PC and CP and be useful in clinical practice.

Accuracy of Imaging Modalities in Choledocholithiasis: A Real-Life Data

In this retrospective study of real-life data, we aimed to determine the diagnostic accuracy in patients with choledocholithiasis of some current imaging modalities, including ultrasonography (US), computerized tomography (CT), magnetic resonance cholangiopancreatography (MRCP), and endoscopic retrograde cholangiopancreatography (ERCP). This study utilized a database of imaging records from 86 consecutive patients with ERCP-proven choledocholithiasis in a single-center outpatient clinic. Features of the stones found, namely number, size, localization, choledochal dilation and cholestasis, were determined using various imaging modalities and liver function tests (LFTs). Our study focused on a total of 86 patients (43 female; 43 male) who underwent the ERCP procedure. Hepatobiliary ultrasound was performed in 71 (82.6%); MRCP in 59 (68.6%); and CT in 13 (15.1%) patients. All 86 patients had choledocholithiasis: 59 (68.6%) with multiple stones and 21 (24.4%) with stones over 10 mm in diameter. Sensitivity for the presence of choledocholithiasis was 40.8% for US, 76.9% for CT, and 86.4% for MRCP, where ERCP was taken as the reference method. Even though US, CT, and MRCP are widely used as noninvasive imaging modalities for CL, in our real-life data their sensitivity for choledocholithiasis was lower than expected. MRCP is preferred when a nontherapeutic but only diagnostic evaluation is aimed for; however, while highly competent in establishing the level of choledochal dilation, it had a low yield in differentiating the localization, size, and number of the stone(s).

Imaging modalities for characterising focal pancreatic lesions

BACKGROUND

Increasing numbers of incidental pancreatic lesions are being detected each year. Accurate characterisation of pancreatic lesions into benign, precancerous, and cancer masses is crucial in deciding whether to use treatment or surveillance. Distinguishing benign lesions from precancerous and cancerous lesions can prevent patients from undergoing unnecessary major surgery. Despite the importance of accurately classifying pancreatic lesions, there is no clear algorithm for management of focal pancreatic lesions.

OBJECTIVES

To determine and compare the diagnostic accuracy of various imaging modalities in detecting cancerous and precancerous lesions in people with focal pancreatic lesions.

SEARCH METHODS

We searched the CENTRAL, MEDLINE, Embase, and Science Citation Index until 19 July 2016. We searched the references of included studies to identify further studies. We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We planned to include studies reporting cross-sectional information on the index test (CT (computed tomography), MRI (magnetic resonance imaging), PET (positron emission tomography), EUS (endoscopic ultrasound), EUS elastography, and EUS-guided biopsy or FNA (fine-needle aspiration)) and reference standard (confirmation of the nature of the lesion was obtained by histopathological examination of the entire lesion by surgical excision, or histopathological examination for confirmation of precancer or cancer by biopsy and clinical follow-up of at least six months in people with negative index tests) in people with pancreatic lesions irrespective of language or publication status or whether the data were collected prospectively or retrospectively.

DATA COLLECTION AND ANALYSIS

Two review authors independently searched the references to identify relevant studies and extracted the data. We planned to use the bivariate analysis to calculate the summary sensitivity and specificity with their 95% confidence intervals and the hierarchical summary receiver operating characteristic (HSROC) to compare the tests and assess heterogeneity, but used simpler models (such as univariate random-effects model and univariate fixed-effect model) for combining studies when appropriate because of the sparse data. We were unable to compare the diagnostic performance of the tests using formal statistical methods because of sparse data.

MAIN RESULTS

We included 54 studies involving a total of 3,196 participants evaluating the diagnostic accuracy of various index tests. In these 54 studies, eight different target conditions were identified with different final diagnoses constituting benign, precancerous, and cancerous lesions. None of the studies was of high methodological quality. None of the comparisons in which single studies were included was of sufficiently high methodological quality to warrant highlighting of the results. For differentiation of cancerous lesions from benign or precancerous lesions, we identified only one study per index test. The second analysis, of studies differentiating cancerous versus benign lesions, provided three tests in which meta-analysis could be performed. The sensitivities and specificities for diagnosing cancer were: EUS-FNA: sensitivity 0.79 (95% confidence interval (CI) 0.07 to 1.00), specificity 1.00 (95% CI 0.91 to 1.00); EUS: sensitivity 0.95 (95% CI 0.84 to 0.99), specificity 0.53 (95% CI 0.31 to 0.74); PET: sensitivity 0.92 (95% CI 0.80 to 0.97), specificity 0.65 (95% CI 0.39 to 0.84). The third analysis, of studies differentiating precancerous or cancerous lesions from benign lesions, only provided one test (EUS-FNA) in which meta-analysis was performed. EUS-FNA had moderate sensitivity for diagnosing precancerous or cancerous lesions (sensitivity 0.73 (95% CI 0.01 to 1.00) and high specificity 0.94 (95% CI 0.15 to 1.00), the extremely wide confidence intervals reflecting the heterogeneity between the studies). The fourth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (dysplasia) provided three tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing invasive carcinoma were: CT: sensitivity 0.72 (95% CI 0.50 to 0.87), specificity 0.92 (95% CI 0.81 to 0.97); EUS: sensitivity 0.78 (95% CI 0.44 to 0.94), specificity 0.91 (95% CI 0.61 to 0.98); EUS-FNA: sensitivity 0.66 (95% CI 0.03 to 0.99), specificity 0.92 (95% CI 0.73 to 0.98). The fifth analysis, of studies differentiating cancerous (high-grade dysplasia or invasive carcinoma) versus precancerous (low- or intermediate-grade dysplasia) provided six tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing cancer (high-grade dysplasia or invasive carcinoma) were: CT: sensitivity 0.87 (95% CI 0.00 to 1.00), specificity 0.96 (95% CI 0.00 to 1.00); EUS: sensitivity 0.86 (95% CI 0.74 to 0.92), specificity 0.91 (95% CI 0.83 to 0.96); EUS-FNA: sensitivity 0.47 (95% CI 0.24 to 0.70), specificity 0.91 (95% CI 0.32 to 1.00); EUS-FNA carcinoembryonic antigen 200 ng/mL: sensitivity 0.58 (95% CI 0.28 to 0.83), specificity 0.51 (95% CI 0.19 to 0.81); MRI: sensitivity 0.69 (95% CI 0.44 to 0.86), specificity 0.93 (95% CI 0.43 to 1.00); PET: sensitivity 0.90 (95% CI 0.79 to 0.96), specificity 0.94 (95% CI 0.81 to 0.99). The sixth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (low-grade dysplasia) provided no tests in which meta-analysis was performed. The seventh analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) provided two tests in which meta-analysis was performed. The sensitivity and specificity for diagnosing cancer were: CT: sensitivity 0.83 (95% CI 0.68 to 0.92), specificity 0.83 (95% CI 0.64 to 0.93) and MRI: sensitivity 0.80 (95% CI 0.58 to 0.92), specificity 0.81 (95% CI 0.53 to 0.95), respectively. The eighth analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) or benign lesions provided no test in which meta-analysis was performed.There were no major alterations in the subgroup analysis of cystic pancreatic focal lesions (42 studies; 2086 participants). None of the included studies evaluated EUS elastography or sequential testing.

AUTHORS' CONCLUSIONS

We were unable to arrive at any firm conclusions because of the differences in the way that study authors classified focal pancreatic lesions into cancerous, precancerous, and benign lesions; the inclusion of few studies with wide confidence intervals for each comparison; poor methodological quality in the studies; and heterogeneity in the estimates within comparisons.

Diagnostic accuracy of different imaging modalities following computed tomography (CT) scanning for assessing the resectability with curative intent in pancreatic and periampullary cancer

BACKGROUND

Periampullary cancer includes cancer of the head and neck of the pancreas, cancer of the distal end of the bile duct, cancer of the ampulla of Vater, and cancer of the second part of the duodenum. Surgical resection is the only established potentially curative treatment for pancreatic and periampullary cancer. A considerable proportion of patients undergo unnecessary laparotomy because of underestimation of the extent of the cancer on computed tomography (CT) scanning. Other imaging methods such as magnetic resonance imaging (MRI), positron emission tomography (PET), PET-CT, and endoscopic ultrasound (EUS) have been used to detect local invasion or distant metastases not visualised on CT scanning which could prevent unnecessary laparotomy. No systematic review or meta-analysis has examined the role of different imaging modalities in assessing the resectability with curative intent in patients with pancreatic and periampullary cancer.

OBJECTIVES

To determine the diagnostic accuracy of MRI, PET scan, and EUS performed as an add-on test or PET-CT as a replacement test to CT scanning in detecting curative resectability in pancreatic and periampullary cancer.

SEARCH METHODS

We searched MEDLINE, Embase, Science Citation Index Expanded, and Health Technology Assessment (HTA) databases up to 5 November 2015. Two review authors independently screened the references and selected the studies for inclusion. We also searched for articles related to the included studies by performing the "related search" function in MEDLINE (OvidSP) and Embase (OvidSP) and a "citing reference" search (by searching the articles that cite the included articles).

SELECTION CRITERIA

We included diagnostic accuracy studies of MRI, PET scan, PET-CT, and EUS in patients with potentially resectable pancreatic and periampullary cancer on CT scan. We accepted any criteria of resectability used in the studies. We included studies irrespective of language, publication status, or study design (prospective or retrospective). We excluded case-control studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed data extraction and quality assessment using the QUADAS-2 (quality assessment of diagnostic accuracy studies - 2) tool. Although we planned to use bivariate methods for analysis of sensitivities and specificities, we were able to fit only the univariate fixed-effect models for both sensitivity and specificity because of the paucity of data. We calculated the probability of unresectability in patients who had a positive index test (post-test probability of unresectability in people with a positive test result) and in those with negative index test (post-test probability of unresectability in people with a positive test result) using the mean probability of unresectability (pre-test probability) from the included studies and the positive and negative likelihood ratios derived from the model. The difference between the pre-test and post-test probabilities gave the overall added value of the index test compared to the standard practice of CT scan staging alone.

MAIN RESULTS

Only two studies (34 participants) met the inclusion criteria of this systematic review. Both studies evaluated the diagnostic test accuracy of EUS in assessing the resectability with curative intent in pancreatic cancers. There was low concerns about applicability for most domains in both studies. The overall risk of bias was low in one study and unclear or high in the second study. The mean probability of unresectable disease after CT scan across studies was 60.5% (that is 61 out of 100 patients who had resectable cancer after CT scan had unresectable disease on laparotomy). The summary estimate of sensitivity of EUS for unresectability was 0.87 (95% confidence interval (CI) 0.54 to 0.97) and the summary estimate of specificity for unresectability was 0.80 (95% CI 0.40 to 0.96). The positive likelihood ratio and negative likelihood ratio were 4.3 (95% CI 1.0 to 18.6) and 0.2 (95% CI 0.0 to 0.8) respectively. At the mean pre-test probability of 60.5%, the post-test probability of unresectable disease for people with a positive EUS (EUS indicating unresectability) was 86.9% (95% CI 60.9% to 96.6%) and the post-test probability of unresectable disease for people with a negative EUS (EUS indicating resectability) was 20.0% (5.1% to 53.7%). This means that 13% of people (95% CI 3% to 39%) with positive EUS have potentially resectable cancer and 20% (5% to 53%) of people with negative EUS have unresectable cancer.

AUTHORS' CONCLUSIONS

Based on two small studies, there is significant uncertainty in the utility of EUS in people with pancreatic cancer found to have resectable disease on CT scan. No studies have assessed the utility of EUS in people with periampullary cancer.There is no evidence to suggest that it should be performed routinely in people with pancreatic cancer or periampullary cancer found to have resectable disease on CT scan.

Comparison of preoperative evaluation of malignant low-level biliary obstruction using plain magnetic resonance and coronal liver acquisition with volume acceleration technique alone and in combination

Background

To evaluate the clinical value of plain magnetic resonance (MR) imaging (including magnetic resonance cholangiopancreatography, MRCP) and coronal liver acquisition with volume acceleration (LAVA) technique in the diagnosis and preoperative assessment of malignant low-level biliary obstruction.

Methods

Forty-one patients with confirmed malignant low-level biliary obstruction were examined by plain MR, MRCP and coronal LAVA techniques. Group 1, plain MR (including MRCP); group 2, coronal LAVA; group 3, plain MR and coronal LAVA. Assessments included positioning, qualitative diagnosis and preoperative evaluation. The results were compared with pathological, endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography results.

Results

There were 14 pancreatic adenocarcinoma, 12 distal common bile duct carcinoma, 10 ampullary carcinoma, and 5 duodenal carcinoma cases. There was no significant difference in accuracy of the three groups’ positioning diagnoses, 87.8, 90.2, and 92.7 %, respectively. The accuracy of the qualitative diagnoses was lower in group 1 at 78.0 %, but not significantly different in groups 2 and 3 at 92.7 and 95.1 %, respectively (P = 0.031, and 0.039, group 1 vs groups 2 and 3, respectively). Thirty-three patients underwent open surgery. There were 19 adjacent organ involvements, 9 vascular involvements, 13 lymph node metastases and 6 liver metastases. 22 patients were verified surgically and histologically for resectable lesions. Plain MR with coronal LAVA imaging showed 85.4 % accuracy, 90.9 % sensitivity, 78.9 % specificity, 83.3 % positive and 88.2 % negative predictive value for resectability.

Conclusions

Plain MR and coronal LAVA techniques are potential noninvasive tools for diagnosis and preoperative assessment of malignant low-level biliary obstruction.

Electronic supplementary material

The online version of this article (doi:10.1186/s40001-015-0188-3) contains supplementary material, which is available to authorized users.

Minimally Invasive Techniques for Resection of Pancreatic Neuroendocrine Tumors

Surgical resection remains the treatment of choice for primary pancreatic neuroendocrine tumors (PNETs), because it is associated with increased survival. Minimally invasive procedures are a safe modality for the surgical treatment of PNETs. In malignant PNETs, laparoscopy is not associated with a compromise in terms of oncologic resection, and provides the benefits of decreased postoperative pain, better cosmetic results, shorter hospital stay, and a shorter postoperative recovery period. Further prospective, multicenter, randomized trials are required for the analysis of these minimally invasive surgical techniques for the treatment of PNETs and their comparison with traditional open pancreatic surgery.

(18)F-FDG-PET/CT findings in pancreatic metastasis

PURPOSE

This study aimed to evaluate the fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) findings and pattern of FDG uptake in pancreatic metastases.

MATERIALS AND METHODS

A total of 19 consecutive patients (26 lesions) with histologically or clinically confirmed pancreatic metastases who had undergone (18)F-FDG-PET/CT were enrolled in this retrospective study. Among the 19 patients, 14 patients underwent abdominal contrast-enhanced CT (ceCT). The location, size and FDG uptake patterns of the pancreatic lesions were recorded. Metabolic activity by means of maximum standardised uptake value (SUVmax) was measured by drawing regions of interest at the site of pancreatic lesions. Twenty pancreatic cancer patients were included in this study as comparative data analysis. The difference of SUVmax between pancreatic metastases and primary pancreatic cancer were compared using the Mann-Whitney U test. P < 0.05 was considered significant.

RESULTS

Three different patterns of FDG uptake could be distinguished in the pancreatic metastatic lesions, including focal nodule or mass, multiple foci and segmental lesion with high FDG uptake. The average SUVmax in pancreatic metastases was 7.8 ± 6.9 versus 7.4 ± 3.9 in primary pancreatic cancer (P = 0.987 > 0.05). Four intrapancreatic isodense nodules in three patients were undetected on ceCT.

CONCLUSION

The described patterns of FDG uptake findings may be helpful for a better characterisation of pancreatic metastases although semiquantitative analysis using SUVmax could not be used as a criterion for differentiating pancreatic metastases from primary pancreatic cancer. FDG-PET/CT has also an advantage in detecting unsuspected pancreatic metastases which cannot be detected by ceCT imaging. Thus, it is a useful adjunct to the described features on CT.

Use of Magnetic Resonance Cholangiopancreatography in Clinical Practice: Not as Good as We Once Thought

BACKGROUND

Magnetic resonance cholangiopancreatography (MRCP) is believed to be a useful tool to evaluate the biliary tree and pancreas for stones, tumors, or injuries to the ductile system. The purpose of this study was to compare the accuracy of MRCP to the gold standard, endoscopic retrograde cholangiopancreatography (ERCP), in our institution.

STUDY DESIGN

We performed a retrospective review of all MRCP followed by ERCP (follow-on ERCP) at a single institution over a 6-year period. Exam findings from MRCP were compared with findings on the follow-on ERCP and compared. Studies were grouped into 2 main classifications: tests being performed for patients with suspected choledocholithiasis (stone disease) and tests being performed for concerns of malignant strictures or duct injuries (non-stone disease).

RESULTS

A total of 81 patients had MRCPs and follow-on ERCPs in this time period. Thirty-six patients had positive findings on MRCP and ERCP for stones in the common duct system, and 14 patients had positive findings on MRCP and subsequent ERCP for masses and strictures of the common duct. Three patients had positive MRCP and ERCP findings for pancreatic duct abnormalities. The specificity and positive predictive value of MRCP were 94% and 98%, respectively. However, 13 of 28 patients had lesions identified on ERCP after a normal MRCP. The sensitivity and negative predictive value were 80% and 54%, respectively.

CONCLUSIONS

Magnetic resonance cholangiopancreatography was not useful in the management algorithm of either stone or non-stone disease of the biliary tree or pancreas. It should be abandoned as a diagnostic tool for work-up of biliary duct pathology.

Serum p53 Antibody Is Not Associated with p53 Immunoreactivity in Patients with Pancreatobiliary Cancers

Background. Recent diagnostic imaging tests contribute to improving the diagnosis of pancreatobiliary cancers. However, it is not practical to perform these tests for all patients as screening. Thus, less-invasive and simple screening tests are still required. A method to detect the IgG antibody induced in serum against the p53 protein accumulating due to p53 gene mutation, as a biomarker, was developed around 1990. Method. 35 patients with pancreatic cancer, 12 patients with biliary tract cancer, and 31 patients with benign pancreatobiliary diseases were entered into this study. Measurement of serum anti-p53 antibody was conducted in all patients. In addition, the rate of p53 protein overexpression was examined in those cases that could be examined pathologically. Result. Among all patients in the pancreatic cancer and biliary tract cancer groups, there was no patient with serum anti-p53 antibody positive value that exceeded the standard value. The rate of p53 protein overexpression was 48.0% in the patients with pancreatobiliary cancers and 0% in the benign pancreatobiliary diseases group. Conclusion. Serum anti-p53 antibody measurement does not contribute to the diagnosis of pancreatobiliary cancers. Instead, traditional p53 immunostaining still appears to be valuable in combination with standard procedures.

Diagnostic Accuracy of Imaging Modalities in the Evaluation of Vascular Invasion in Pancreatic Adenocarcinoma: A Meta-Analysis

Background

The extent of vascular invasion is a key factor determining the resectability of non-metastatic pancreatic adenocarcinoma. The purpose of this study is to determine the diagnostic accuracy of computed tomography (CT), endoscopic ultrasound (EUS), and magnetic resonance imaging (MRI) in the pre-operative evaluation of vascular invasion in pancreatic adenocarcinoma, with surgery as the reference standard.

Methods

A search of the MEDLINE database for relevant articles in the English language published between January 2000 and February 2009 was performed. From each study, 2 × 2 tables were obtained, and pooled sensitivity, specificity, positive likelihood ratios, negative likelihood ratios and diagnostic odds ratios were calculated for each modality, along with a summary receiver operating characteristics (SROC) curve.

Results

16 studies with a total of 797 patients who had surgical assessment of vascular invasion were included in the analysis. Several studies evaluated more than one imaging modality, allowing 24 datasets to be obtained in total. Sensitivity was highest for CT (0.73, 95% CI 0.67 - 0.79), followed by EUS (0.66, 95% CI 0.56 - 0.75) and MRI (0.63, 95% CI 0.48 - 0.77). The specificity for all three imaging modalities was comparable. The diagnostic odds ratios for CT, EUS and MRI were 45.9 (95% CI 18.0 - 117.4), 23.0 (95%CI 9.4 - 56.6), 23.9 (95% CI 5.4 - 105.1) respectively.

Conclusion

CT was more accurate than EUS and MRI in the evaluation of vascular invasion in pancreatic adenocarcinoma and should be the first line investigation in pre-operative staging.

The usefulness of (18)F-FDG PET/MRI fusion image in diagnosing pancreatic tumor: comparison with (18)F-FDG PET/CT

PURPOSE

This study aimed at demonstrating the feasibility of retrospectively fused (18)F FDG-PET and MRI (PET/MRI fusion image) in diagnosing pancreatic tumor, in particular differentiating malignant tumor from benign lesions. In addition, we evaluated additional findings characterizing pancreatic lesions by FDG-PET/MRI fusion image.

METHODS

We analyzed retrospectively 119 patients: 96 cancers and 23 benign lesions. FDG-PET/MRI fusion images (PET/T1 WI or PET/T2WI) were made by dedicated software using 1.5 Tesla (T) MRI image and FDG-PET images. These images were interpreted by two well-trained radiologists without knowledge of clinical information and compared with FDG-PET/CT images. We compared the differential diagnostic capability between PET/CT and FDG-PET/MRI fusion image. In addition, we evaluated additional findings such as tumor structure and tumor invasion.

RESULTS

FDG-PET/MRI fusion image significantly improved accuracy compared with that of PET/CT (96.6 vs. 86.6 %). As additional finding, dilatation of main pancreatic duct was noted in 65.9 % of solid types and in 22.6 % of cystic types, on PET/MRI-T2 fusion image. Similarly, encasement of adjacent vessels was noted in 43.1 % of solid types and in 6.5 % of cystic types. Particularly in cystic types, intra-tumor structures such as mural nodule (35.4 %) or intra-cystic septum (74.2 %) were detected additionally. Besides, PET/MRI-T2 fusion image could detect extra benign cystic lesions (9.1 % in solid type and 9.7 % in cystic type) that were not noted by PET/CT.

CONCLUSIONS

In diagnosing pancreatic lesions, FDG-PET/MRI fusion image was useful in differentiating pancreatic cancer from benign lesions. Furthermore, it was helpful in evaluating relationship between lesions and surrounding tissues as well as in detecting extra benign cysts.

Liver blood supply after a modified Appleby procedure in classical and aberrant arterial anatomy

Reported here are two cases of a modified Appleby operation for borderline resectable ductal adenocarcinoma of the pancreatic body, in one of which a R0 distal resection was attended to by excision, not only of the celiac axis, but also of the common and left hepatic arteries in the presence of arterial anatomic variation Michels, type VIIIb. The possibility and avenues of the maintenance of the blood supply to the left hepatic lobe after surgical aggression of this kind are demonstrated employing computed tomography (CT) and 3-D CT angiography. Furthermore, both cases highlight all important worrisome aspects of pancreatic cancer resectability prediction.

Abdominal ultrasonography in detecting and surgical treatment of pancreatic carcinoma

THE AIM OF THE STUDY

was to asses the clinical value of percutaneous abdominal ultrasonography in diagnosis, staging and surgical treatment of patients with pancreatic carcinoma.

MATERIAL AND METHODS

Prospective clinical trial on diagnostic accuracy of percutaneous abdominal ultrasonography was conducted in 409 consecutive patients with pancreatic cancer which were operated on at the I Dept. of General Surgery in Cracow between 2000 and 2010.

RESULTS

Diagnostic accuracy of percutaneous abdominal ultrasonography in pancreatic cancer was 91,1%. The accuracy in detecting different stages of local advancement according to TNM classification was assessed respectively 92.3%-T1, 91.3%-T2, 89.4%-T3, 92.1%-T4, a whole T1-T4 on 91.3%. Diagnostic accuracy of percutaneous abdominal ultrasonography in diagnosis of metastasis to lymph nodes, vascular infiltration, and resectability was respectively 80.7%, 86%, 91.4%.

CONCLUSIONS

Percutaneous abdominal ultrasonography has high diagnostic accuracy in diagnosis, staging and predicting surgical treatment of patients with pancreatic carcinoma.

Radiological and nuclear medicine imaging of gastroenteropancreatic neuroendocrine tumours

Neuroendocrine tumours (NETs) comprise a heterogeneous group of neoplasms with very varying clinical expression. A functioning NET, for instance in the pancreas, may be very small and yet give rise to severe endocrine symptoms whereas a patient with a small bowel tumour may present with diffuse symptoms and disseminated disease with a palpable bulky liver. Imaging of NETs is therefore challenging and the imaging needs in the various patients are diverse. The basic modalities for NET imaging are computed tomography (CT) or magnetic resonance imaging (MRI) in combination with somatostatin receptor imaging (SMI) by scintigraphy with 111In-labelled octreotide (OctreoScan) or more recently by positron emission tomography (PET) with 68Ga-labelled somatostatin analogues. In this review these various morphological and functional imaging modalities and important methodological aspects are described. Imaging requirements for the various types of NETs are discussed and typical image findings are illustrated.

Ductal adenocarcinoma of the pancreatic head: A focus on current diagnostic and surgical concepts

Complete surgical resection still remains the only possibility of curing pancreatic cancer, however, only 10% of patients undergo curative surgery. Pancreatic resection currently remains the only method of curing patients, and has a 5-year overall survival rate between 7%-34% compared to a median survival of 3-11 mo for unresected cancer. Pancreatic surgery is a technically demanding procedure requiring highly standardized surgical techniques. Nevertheless, even in experienced hands, perioperative morbidity rates (delayed gastric emptying, pancreatic fistula etc.) are as high as 50%. Different strategies to reduce postoperative morbidity, such as different techniques of gastroenteric reconstruction (pancreatico-jejunostomy vs pancreatico-gastrostomy), intraoperative placement of a pancreatic main duct stent or temporary sealing of the main pancreatic duct with fibrin glue have not led to a significant improvement in clinical outcome. The perioperative application of somatostatin or its analogues may decrease the incidence of pancreatic fistulas in cases with soft pancreatic tissue and a small main pancreatic duct (< 3 mm). The positive effects of external pancreatic main duct drainage and antecolic gastrointestinal reconstruction have been observed to decrease the rate of pancreatic fistulas and delayed gastric emptying, respectively. Currently, the concept of extended radical lymphadenectomy has been found to be associated with higher perioperative morbidity, but without any positive impact on overall survival. However, there is growing evidence that portal vein resections can be performed with acceptable low perioperative morbidity and mortality but does not achieve a cure.

Preoperative vascular evaluation with computed tomography and magnetic resonance imaging for pancreatic cancer: a meta-analysis

OBJECTIVES

Vascular invasion (VI) is the most important factor in assessing operability for pancreatic cancer. The accuracy of preoperative vascular staging with computed tomography (CT) and magnetic resonance imaging (MRI) was examined using meta-analysis.

METHODS

Published articles in pancreatic cancer comparing diagnostic accuracy of CT with MRI for VI confirmed on histology were searched from MEDLINE, EMBASE and ISI Web of Science databases. Pooled sensitivity, specificity, likelihood ratio, summary receiver operating characteristic (SROC) curve and area under curve (AUC) were analysed by SPSS 13.0 and Revmen 5.1.

RESULTS

Eight studies (n = 296) met the inclusion criteria. The pooled sensitivity of CT and MRI in diagnosing VI was 71% (95% CI, 64-78) and 67% (95% CI, 59-74), pooled specificity 92% (95% CI, 89-95) and 94% (95% CI, 91-96), positive likelihood ratio 6.33 (95% CI, 4.51-8.87) and 6.58 (95% CI, 4.62-9.37), negative likelihood ratio 0.34 (95% CI, 0.27-0.43) and 0.38 (95% CI, 0.30-0.47), and AUCs 0.87 and 0.76 (p = 0.63), respectively. There was no significant difference between CT and MRI for preoperative diagnosis of VI. Subgroup analysis of 4 studies (n = 143) showed no significant difference between CT and MRI in preoperative diagnosis of venous or arterial invasion (p = 0.73 and p = 0.81, respectively). When CT was compared with MRA in 3 studies (n = 110), again there was no significant difference for preoperative staging of VI (p = 0.54).

CONCLUSIONS

Both CT and MRI are underreporting vascular invasion preoperatively in pancreatic cancer. MRA does not add any additional information on vascular staging when compared with CT and MRI.

Diagnostic value of dynamic contrast-enhanced magnetic resonance imaging in the evaluation of the biliary obstruction

Purpose. In this study, our purpose was to investigate the diagnostic efficacy of the dynamic contrast-enhanced magnetic resonance imaging (MRI) method in the patients with bile duct obstruction. Materials and Methods. 108 consecutive patients (53 men, 55 women, mean age; 55.77 ± 14.62, range 18–86 years) were included in this study. All the patients underwent conventional upper abdomen MRI using intravenous contrast material (Gd-DTPA) and MRCP in 1.5 Tesla MRI scanner. MRCP images were evaluated together with the T1 and T2w images, and both biliary ducts and surrounding tissues were examined for possible pathologies that may cause obstruction. Results. MRI/MRCP findings compared with final diagnoses, MRI/MRCP in the demonstration of bile duct obstruction sensitivity 96%, the specificity 100%, and accuracy 96.3%, in the detection of presence and level of obstruction, the sensitivity 96.7%, specificity 100%, and accuracy 97.2%, in the diagnosis of choledocholithiasis, the sensitivity 82.3%, specificity 96%, and accuracy 91.7%, and in the determination of the character of the stenosis, sensitivity 95.6%, specificity 91.3%, and accuracy 94.5% were found. Conclusion. The combination of dynamic contrast-enhanced MRI and MRCP techniques in patients with suspected biliary obstruction gives the detailed information about the presence of obstruction, location, and causes and is a highly specific and sensitive method.

MR imaging versus PET/CT for evaluation of pancreatic lesions

PURPOSE

To retrospectively determine the diagnostic accuracy of magnetic resonance imaging (MRI) and combined positron emission tomography/computed tomography (PET/CT) in the differential diagnosis of benign and malignant pancreatic lesions.

MATERIALS AND METHODS

Twenty-seven patients (15 women/12 men, mean age 56.5 years) with MR imaging and PET/CT studies performed to differentiate benign and malignant pancreatic lesions were identified between October 2008 and October 2010. Both MR and PET/CT data sets were retrospectively and blindly evaluated by two independent readers (4 readers total) with different degrees of experience, using a visual five-point score system. The results were correlated with final diagnosis obtained by histopathology.

RESULTS

17 patients had malignant diseases and 10 patients had benign diseases. Depending on the observer, the sensitivity, specificity, positive predictive value and negative predictive value of MRI varied between 88-94%, 50-80%, 75-89% and 71-89% respectively. Sensitivities, specificities, positive predictive values and negative predictive values of PET/CT were 73%, 56%, 73% and 56% respectively. The diagnostic accuracy of MR for the differential diagnosis of pancreatic lesions was 74-89%, compared with 67% for PET/CT. The weighted Cohen's kappa coefficient was 0.47 at MR and 0.53 at PET/CT.

CONCLUSION

MRI achieved higher sensitivity and specificity in the differential diagnosis of pancreatic lesions.

Staging laparoscopy for proximal pancreatic cancer in a magnetic resonance imaging-driven practice: what's it worth?

BACKGROUND

Preoperative imaging is often inadequate in excluding unresectable pancreatic cancer. Accordingly, many groups employ staging laparoscopy (SL), although none have evaluated SL after preoperative magnetic resonance imaging (MRI). We performed a retrospective, indirect cost-effectiveness analysis of SL after MRI for pancreatic head lesions.

METHODS

All MRI scans administered for proximal pancreatic cancer between 2004 and 2008 were reviewed and the clinical course of each patient determined. We queried our billing database to render average total costs for all inpatients with proximal pancreatic cancer who underwent pancreaticoduodenectomy, palliative bypass or an endoscopic stenting procedure. We then performed an indirect evaluation of the cost of routine SL.

RESULTS

The average costs of hospitalization for patients undergoing pancreaticoduodenectomy, open palliative bypass and endoscopic palliation were: US$26, 122.43, US$21, 957.18 and US$11, 304.00, respectively. The calculated cost of SL without laparotomy was US$2966.25 or US$1538.61 prior to laparotomy. The calculated cost of treating unresectable disease by outpatient laparoscopy followed by endoscopy was US$5943.17. Routine SL would increase our costs by US$76, 967.46 (3.6%).

CONCLUSIONS

Staging laparoscopy becomes cost-effective by diverting unresectable patients from operative to endoscopic palliation. Given the paucity of missed metastases on MRI, the yield of SL is marginal and its cost-effectiveness is poor. Future studies should address the utility of SL by both examining this issue prospectively and investigating the cost-effectiveness of endoscopic vs. surgical palliation in a manner that takes account of survival and quality of life data.

Biliary, pancreatic, and hepatic imaging for the general surgeon

Technologic advancements have allowed imaging modalities to become more useful in the diagnosis of hepatobiliary and pancreatic disorders. Computed tomography scanners now use multidetector row technology with contrast-delayed imaging for quicker and more accurate imaging. Magnetic resonance imaging with cholangiopancreatography can more clearly delineate liver lesions and the biliary and pancreatic ducts, and can diagnose pathologic conditions early in their course. Newer technologies, such as single-operator cholangioscopy and endoscopic ultrasonography, have sometimes shown superiority to traditional modalities. This article addresses the literature regarding available imaging techniques in the diagnosis and treatment of common surgical hepatobiliary and pancreatic diseases.

Distal pancreatectomy with en bloc resection of the celiac trunk for extended pancreatic tumor disease: an interdisciplinary approach

PURPOSE

Infiltration of the celiac trunk by adenocarcinoma of the pancreatic body has been considered a contraindication for surgical treatment, thus resulting in a very poor prognosis. The concept of distal pancreatectomy with resection of the celiac trunk offers a curative treatment option but implies the risk of relevant hepatic or gastric ischemia. We describe initial experiences in a small series of patients with left celiacopancreatectomy with or without angiographic preconditioning of arterial blood flow to the stomach and the liver.

MATERIALS AND METHODS

Between January 2007 and October 2009, six patients underwent simultaneous resection of the celiac trunk for adenocarcinoma of the pancreatic body involving the celiac axis. In four of these cases, angiographic occlusion of the celiac trunk before surgery was performed to enhance collateral flow from the gastroduodenal artery. Radiologic and surgical procedures, findings, and outcome were analyzed retrospectively.

RESULTS

Complete tumor removal (R0) succeeded in two patients, whereas four patients underwent R1-tumor resection. After surgery, one of the two patients without angiographic preparation experienced an ischemic stomach perforation 1 week after surgery. The other patient died from severe bleeding from an ischemic gastric ulcer. Of the four patients with celiac trunk embolization, none presented ischemic complications after surgery. Mean survival was 371 days.

CONCLUSION

In this small series, ischemic complications after celiacopancreatectomy occurred only in those patients who did not receive preoperative celiac trunk embolization.

An MRI-driven practice: a new perspective on MRI for the evaluation of adenocarcinoma of the head of the pancreas

OBJECTIVES

The purpose of the study was to describe the MRI-driven management of masses at the head of the pancreas.

MAIN OUTCOME MEASURES

The main outcome measure was tumor resectability.

METHODS

A retrospective review of prospective radiographic diagnoses was undertaken.

RESULTS

Between 2004 and 2008, we have treated 124 patients for a radiographic diagnosis of adenocarcinoma of the head of the pancreas. This diagnosis was correct in 96.0% of the time. MRI was 100% sensitive in determining resectability, 73.2-78.9% specific, and had an overall accuracy of 86.3-87.5%. MRI could detect venous and arterial involvement with 95% and 95.9% accuracy, respectively, and missed only six metastases.

CONCLUSION

MRI is a useful tool in the preoperative imaging of pancreatic head lesions that is highly sensitive and very specific for resectable disease. Prospective trials of MRI in this setting are indicated.

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.

Comparison between multislice CT and MR imaging in the diagnostic evaluation of patients with pancreatic masses

PURPOSE

This study compared the results of multislice computed tomography (MSCT) and high-field magnetic resonance imaging (MRI) in the diagnostic evaluation of pancreatic masses.

MATERIALS AND METHODS

Forty patients with clinical and ultrasonographic evidence of pancreatic masses underwent MSCT and MRI. The majority of patients (31/40, 78%) had proven malignant pancreatic tumours (24 ductal adenocarcinoma, six mucinous cystadenocarcinoma, one intraductal papillary mucinous carcinoma), whereas the remaining patients (9/40, 22%) were found to have benign lesions (eight chronic pancreatitis, one serous cystadenoma). Results of the imaging studies were compared with biopsy (n=33) and/or histology (n=7) findings to calculate sensitivity, specificity, accuracy and positive (PPV) and negative (NPV) predictive value for correct identification of tumours and evaluation of resectability of malignancies.

RESULTS

Both for tumour identification and resectability, MSCT and MRI had comparable diagnostic accuracy, with no statistically significant differences between them. Tumour identification CT/MRI: accuracy 98/98%, sensitivity 100/100%, specificity 88/88%, PPV 97/97%, NPV 100/100%; tumour resectability CT/MRI: accuracy 94/90%, sensitivity 92/88%, specificity 100/100%, PPV 100/100%, NPV 78/70%.

CONCLUSIONS

MRI represents a valid diagnostic alternative to CT in the evaluation of patients with pancreatic masses, both for correct identification and characterisation of primary lesions and to establish resectability in the case of malignancies. New high-field MRI equipment allows optimal imaging quality with good contrast resolution in evaluating the upper abdomen.

Patients with pancreatic adenocarcinoma benefit from staging laparoscopy

BACKGROUND

Unnecessary laparotomy in patients with advanced pancreatic cancer may both compromise the quality of life and delay the initiation of more appropriate therapy. Very often, peritoneal small liver metastases and true local status cannot be fully determined without surgery. Laparoscopy may spare laparotomy and decrease morbidity for patients with nonresectable advanced disease. The aim of this study was to determine the impact of laparoscopy in patients with potentially resectable adenocarcinoma of the pancreas.

MATERIALS AND METHODS

We reviewed the records of patients undergoing pancreatic surgery at the University of Nebraska Medical Center from October 2001 to April 2005. A total of 59 patients were included in the study. All patients were staged radiographically with a high resolution helical computed tomography scan and their tumors were considered resectable. Thirty-seven patients underwent staging laparoscopy while 22 proceeded directly to laparotomy.

RESULTS

Of the 37 patients who underwent laparoscopic staging, 9 (24.3%) were detected to have metastatic disease or advanced tumor; the remaining 28 (75.7%) patients with negative laparoscopy proceeded to laparotomy. Of those, 24 patients (85.7%) underwent pancreatic resection with curative intent, while 4 patients had metastatic or locally advanced disease at subsequent laparotomy which was missed on staging laparoscopy (false negative rate of 14.3%). Of the 22 patients who proceeded directly to laparotomy, 16 (72.7%) received curative Whipple resection and 6 (27.3%) were found to have advanced disease and received bypass procedures or biopsy alone.

CONCLUSION

These findings suggest that staging laparoscopy is beneficial in a significant proportion of patients deemed resectable by routine noninvasive preoperative studies. We plan to add intraoperative laparoscopic ultrasound to our staging protocol in order to decrease the false negative rate.

Imaging features of intraductal papillary mucinous neoplasms of the pancreas in multi-detector row computed tomography

AIM: To retrospectively evaluate the imaging features of pancreatic intraductal papillary mucinous neoplasms (IPMNs) in multi-detector row computed tomography (MDCT).

METHODS: A total of 20 patients with pathologically-confirmed intraductal papillary mucinous neoplasms (IPMNs) were included in this study. Axial MDCT images combined with CT angiography (CTA) and multiplanar volume reformations (MPVR) or curved reformations (CR) were preoperatively acquired. Two radiologists (Tan L and Wang DB) reviewed all the images in consensus using an interactive picture archiving and communication system. The disputes in readings were resolved through consultation with a third experienced radiologist (Chen KM). Finally, the findings and diagnoses were compared with the pathologic results.

RESULTS: The pathological study revealed 12 malignant IPMNs and eight benign IPMNs. The diameters of the cystic lesions and main pancreatic ducts (MPDs) were significantly larger in malignant IPMNs compared with those of the benign IPMNs (P < 0.05). The combined-type IPMNs had a higher rate of malignancy than the other two types of IPMNs (P < 0.05). Tumors with mural nodules and thick septa had a significantly higher incidence of malignancy than tumors without these features (P < 0.05). Communication of side-branch IPMNs with the MPD was present in nine cases at pathologic examination. Seven of them were identified from CTA and MPVR or CR images. From comparison with the pathological diagnosis, the sensitivity, specificity, and accuracy of MDCT in characterizing the malignancy of IPMN of the pancreas were determined to be 100%, 87.5% and 95%, respectively.

CONCLUSION: MDCT with CTA and MPVR or CR techniques can elucidate the imaging features of IPMNs and help predict the malignancy of these tumors.

[MRI for malignant pancreatic tumors]

In recent years continuous advancements in software and hardware technology of modern MRI systems have contributed to substantial progress in the field of pancreatic tumor imaging. Despite technical advances in abdominal MRI, multislice CT still remains the preferential diagnostic tool for pancreatic lesions. In the majority of cases the essential clinical questions can thereby be answered with a high degree of accuracy. However, in dilemma cases state-of-the-art MR imaging can provide relevant information for the diagnosis allowing an optimal therapeutic concept. This report gives an overview on possible applications for MRI in the diagnostic evaluation of malignant pancreatic tumors.

MR imaging for predicting the recurrence of pancreatic carcinoma after surgical resection

OBJECTIVE

To study the relationship of characteristics of pancreatic carcinoma on MR imaging to tumor recurrence time after surgical resection.

MATERIALS AND METHODS

Twenty-seven patients with pancreatic carcinoma were followed up at least 2 years after surgical resection of the tumor. All patients had MR imaging within 1 month before surgery. The tumor's size, signal intensity, local and vascular invasion, abdominal lymphadenopathy on MR imaging and the positive surgical margin were noted. The results from MR imaging were compared with the duration after surgery until tumor recurrence and with the positive surgical margin.

RESULTS

59% of patients had various degree of extrapancreatic invasion. The tumor recurrence times were, respectively, 24+/-21 months and 26+/-29 months in patients with and without vascular invasion (P=0.79). The combination of vascular with local invasion showed a correlation to the time of tumor recurrence (r=-0.34; P<0.05). Patients with positive surgical margins had a higher local invasion score on MR imaging and a shorter recurrence time than those with negative surgical margins. The number and size of lymph nodes were not related with tumor recurrence time.

CONCLUSION

MR imaging was useful for predicting the recurrence of pancreatic carcinoma after surgical resection. Local invasion associated with and without vascular invasion on MR imaging was the indicator for the tumor recurrence.

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.

Prediction of vascular involvement and resectability by multidetector-row CT versus MR imaging with MR angiography in patients who underwent surgery for resection of pancreatic ductal adenocarcinoma

PURPOSE

To compare the diagnostic value of dual-phase multidetector-row CT (MDCT) and MR imaging with dual-phase three-dimensional MR angiography (MRA) in the prediction of vascular involvement and resectability of pancreatic ductal adenocarcinoma.

METHODS AND MATERIALS

116 patients with proven pancreatic adenocarcinoma underwent both MDCT and combined MR imaging prior to surgery. Of 116 patients, 56 who underwent surgery were included. Two radiologists independently attempt to assess detectability, vascular involvement and resectability of pancreatic adenocarcinoma on both images. Results were compared with surgical findings and statistical analysis was performed.

RESULTS

MDCT detected pancreatic mass in 45 of 56 patients (80.3%) and MR imaging in 44 patients (78.6%). In assessment of vascular involvement, sensitivities and specificities of MDCT were 61% and 96% on a vessel-by-vessel basis, respectively. Those of MR imaging were 57% and 98%, respectively. In determining resectability, sensitivities and specificities of MDCT were 90% and 65%, respectively. Those of MR imaging were 90% and 41%, respectively. There was no statistical difference in detecting tumor, assessing vascular involvement and determining resectability between MDCT and MR imaging (p=0.5).

CONCLUSION

MDCT and MR imaging with MRA demonstrated an equal ability in detection, predicting vascular involvement, and determining resectability for a pancreatic ductal adenocarcinoma.

MRCP vs. ERCP in the evaluation of biliary pathologies: review of current literature

OBJECTIVE

Recently developed magnetic resonance (MR) techniques permit fast and correct imaging of the entire biliary tree with a high spatial resolution. The aim of this study was to compare the diagnostic potential of one of these new MR sequences in magnetic resonance cholangiopancreatography (MRCP) procedure and endoscopic retrograde cholangiopancreatography (ERCP) with review of current literatures.

METHODS

A total of 295 patients were enrolled in this study prospectively. Of these, 11 were excluded from the study due to inadequate MRCP image quality and 15 more were excluded due to unsuccessful cannulation during ERCP. Thus, finally 269 patients (124 men and 145 women with a mean age of 57 years; range: 23-92 years) were included. The MRCP procedure was performed before the ERCP in all cases. All MRCP studies were performed with recently developed new MR technique using a heavily T2-weighted turbo spin echo (TSE) sequence. This TSE sequence is currently one of the most widely used multiplanar 3-D MR technique, having a high spatial resolution and fast imaging capacity.

RESULTS

The study participants were classified into four main groups; normal into group I, stone disease into group II, tumor into group III and others into group IV. Group I consisted of 228 patients who had a normal pancreaticobiliary tree on both the MRCP and ERCP examinations. In group II there were 18 patients, for whom the MRCP had a 88.9% sensitivity and a 100% specificity for diagnosing biliary stone disease. Its positive predictive value (PPV), negative predictive value (NPV) and accuracy rates were 100%, 99.2% and 99.2%, respectively. The MRCP had a 100% sensitivity and a 100% specificity for 20 patients in group III. It also had 100% PPV, 100% NPV, and 100% total accuracy rates in this group. In three patients in group IV, the MRCP had a 100% sensitivity and specificity, respectively. Its PPV, NPV and accuracy were 100%, 100% and 100%, respectively.

CONCLUSION

MRCP is used with increasing frequency as a non-invasive alternative to ERCP and the diagnostic results of MRCP with a heavily T2-weighted TSE MR sequence and ERCP are comparable with high accuracy in various hepatobiliary pathologies.

CT and MR imaging of pancreatic cancer

Computed tomography (CT) and magnetic resonance imaging (MRI) are emerging noninvasive techniques for imaging of the pancreas. Based on multislice technology, CT enables multiplanar imaging of the pancreas (multislice-CT, MSCT) with a high contrast between vessels and parenchyma. In addition, MRI of the pancreas including the imaging of the lumina of the biliary tree and the pancreatic duct (magnetic resonance cholangiopancreaticography, MRCP) and the abdominal vessels (MR angiography, MRA) has become available for daily clinical practice in most hospitals. The addition of multiplanar and curved reformations may increase the sensitivity of CT and improves its agreement with surgical findings. Beyond abdominal MR imaging, techniques such as magnetic resonance cholangiopancreaticography (MRCP) and MR angiography should be integrated in the imaging protocol whenever possible.

Brachytherapy of liver metastases

Brachytherapy for the treatment of liver metastases is a novel approach. In this procedure, techniques of locally ablative treatment in interventional radiology and radiation therapy are combined. After computed tomography (CT)-guided percutaneous implantation of catheters into the hepatic tumor, the irradiation is performed in an afterloading technique. This minimally invasive procedure offers circumscriptive high-dose rate irradiation of the lesion to treat in a single session, irrespective of breathing motion or potential cooling effects of neighboring vessels. Good local control rates have been achieved in several tumor entities, including both secondary and primary malignancies of the liver. This article gives an overview of the application technique, possible adverse events, and outcome with special attention to the pancreatic cancer scenario.

Nuclear medical methods for the diagnosis of pancreatic cancer: positron emission tomography

The functional imaging approach of nuclear medicine offers important information for the characterization of a tumor's pathobiology. In oncology, positron emission tomography (PET) especially has had great impact on the staging of tumor patients and the assessment of therapy. Both the development of new, tumor-specific, tracers and the introduction of by software- and hardware-driven image fusion emphasize the potential of this modality for an all-embracing diagnostic modality.

Focal pancreatic mass: distinction of pancreatic cancer from chronic pancreatitis using gadolinium-enhanced 3D-gradient-echo MRI

PURPOSE

To determine the accuracy of MRI including T1-weighted gadolinium (Gd)-enhanced three-dimensional-gradient-echo (3D-GE) sequences to distinguish pancreatic cancer from chronic pancreatitis in patients with pancreatic mass or focal enlargement.

MATERIALS AND METHODS

The study included 22 patients (15 males and seven females; mean age +/- SD, 56.2 +/- 11.5 years) with pancreatic mass or focal enlargement. Fourteen had pancreatic carcinoma and eight had chronic pancreatitis based on the histopathological and clinical findings. MRI examinations of all patients were retrospectively evaluated by two independent reviewers for the predetermined imaging findings of carcinoma and chronic pancreatitis. The accuracy of MRI for differentiating pancreatic carcinoma from chronic pancreatitis was determined. MRI findings of both entities were compared using t-tests, chi-squared tests, and logistic regression analyses for the differentiation of these two entities. The extent of agreement between two reviewers was determined with Kappa statistics.

RESULTS

The sensitivity and specificity of MRI including T1-weighted 3D-GE sequences for differentiating pancreatic carcinoma from chronic pancreatitis were 93% (13/14) and 75% (6/8), respectively. The most discriminative finding for pancreatic carcinoma was relative demarcation of the mass compared to background pancreas in contrast to chronic pancreatitis on post-Gd 3D-GRE sequences (P < 0.05).

CONCLUSION

MRI including Gd-enhanced T1-weighted 3D-GE sequences can differentiate pancreatic carcinoma from chronic pancreatitis successfully in most cases.

Pancreatic adenocarcinoma: diagnosis and staging using multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI)

Pancreatic adenocarcinoma continues to be a leading cause of cancer death in the Western world and is amongst the leading gastrointestinal cancers. The incidence of pancreatic cancer has been stable or slowly rising in the past few decades. Overall the prognosis is poor with 5-year survival rates still under 5%. Therefore early detection and accurate staging of these tumors is crucial for optimal treatment.