Pancreatic Protocol CT Research Articles

Assessment of Arterial Involvement in Pancreatic Cancer: Utility of Reconstructed CT Images Perpendicular to Artery.

The purpose of this study was to investigate the utility of reconstructed CT images perpendicular to the artery for assessing arterial involvement from pancreatic cancer and compare the interobserver variability between it and the current diagnostic imaging method. This retrospective study included patients with pancreatic cancer in the pancreatic body or tail who underwent preoperative pancreatic protocol CT and distal pancreatectomy. Five radiologists used axial and coronal CT images (current method) and perpendicular reconstructed CT images (proposed method) to determine if the degree of solid soft-tissue contact with the splenic artery was ≤180° or >180°. The generalized estimating equations were used to compare the diagnostic performance of solid soft-tissue contact >180° between the current and proposed methods. Fleiss' ĸ statistics were used to assess interobserver variability. The sensitivity and negative predictive value for diagnosing solid soft-tissue contact >180° were higher (p < 0.001 for each) and the specificity (p = 0.003) and positive predictive value (p = 0.003) were lower in the proposed method than the current method. Interobserver variability was improved in the proposed method compared with the current method (ĸ = 0.87 vs. 0.67). Reconstructed CT images perpendicular to the artery showed higher sensitivity and negative predictive value for diagnosing solid soft-tissue contact >180° than the current method and demonstrated improved interobserver variability.

Abstract A002: A phase II study of peri-operative modified FOLFIRINOX in localized pancreatic ductal adenocarcinoma (PDAC)

Abstract Introduction: Advances in adjuvant chemotherapy with 5-fluorouracil, irinotecan, and oxaliplatin (FFX) have improved survival for patients (pts) with resectable PDAC yet few are cured by the current standard of care. Neoadjuvant FFX may lead to early control of micrometastasis and enhance cure rates for this aggressive malignancy. Methods: We performed a single-arm phase-2 clinical trial for resectable PDAC evaluating 6 months of perioperative modified (m) FFX (NCT02047474). Patients underwent baseline pancreatic protocol CT and were reviewed for resectability by a multidisciplinary panel. Enrolled pts received 6 cycles of neoadjuvant mFFX followed by surgery and 6 cycles of adjuvant mFFX. The primary endpoint was a ≥ 66% 12-month progression-free survival (PFS). Additional endpoints included overall survival (OS), circulating tumor DNA (ctDNA), tumor molecular features and tumor Keratin 17 levels. Whole blood was prospectively collected and processed to stored plasma (median volume 5.4 mL, range: 2.6 – 10.2) for retrospective ctDNA analysis using a personalized, tumor-informed ctDNA assay (SignateraTM). Survival rates were estimated by Kaplan-Meier. Results: Forty-six pts enrolled with 63 months median follow up, median age of 65 [R 46–80], 36 (78%) were ECOG 0, 30 (65%) had an endobiliary stent and no pts had staging laparoscopy. All pts started mFFX, and 37 pts (80%) completed all 6 preop cycles. Thirty-three pts (72%) underwent surgery with 3 pts developing investigator-assessed progression during neoadjuvant mFFX. Six pts were unresectable intraoperatively, and 27 pts (59%) underwent resection per protocol (25 R0, 2 R1). Ten additional pts underwent surgery off protocol. The 12-month PFS was 78% (95% CI: 64.2–94.4), median PFS and OS were 36.5 months (95% CI: 16.6–74.5) and 37.2 months (95% CI 17.5–not reached), respectively. Two-year OS was 59% (95% CI: 45.8–74.7). Baseline ctDNA was detected in 16/22 (73%) pts, and after 6 cycles of mFFX ctDNA was detected in 3/17 (18%) of pts. Patients with a positive ctDNA test 4 weeks post-resection had worsened PFS (HR 34.0, 95% CI: 2.6-4758.6; P = 0.006) and OS (HR: 11.7, 95% CI: 1.5–129.9; P = 0.021) compared to ctDNA negative. Mutational signature analysis revealed predominant signatures to be COSMIC signatures SBS1 and SBS5 (age related), and SBS15 (mismatch repair deficiency associated) which was associated with improved OS. Using Keratin 17 as a biomarker of the basal molecular subtype, either in diagnostic needle aspirates or surgical specimens, we found that high K17 expression was associated with worse survival. Conclusion: The perioperative mFFX clinical trial for resectable PDAC met its primary endpoint with a promising survival rate, and R0 resection rate of 93%. These findings warrant further evaluation in a randomized clinical trial. Most pts with detectable ctDNA at baseline experience ctDNA clearance after 6 cycles of neoadjuvant mFFX. In the post-operative setting, ctDNA positivity was strongly associated with recurrence. Signature SBS15 and low K17 were associated with improved OS. Citation Format: Michael Cecchini, Ronald Salem, Marie Robert, Suzanne Czerniak, Moein Rajaei, Jeffrey Townsend, Ondrej Blaha, Daniel Zelterman, Jaykumar Thumar, Jeremy Kortmansky, Wajih Zaheer, Neal Fischbach, Justin Persico, Stacey Stein, Sajid Khan, Charles Cha, Kevin Billingsley, John Kunstman, Sumedha Chowdhury, Robert Tseng, Carlos Mauricio, Deanne Yugawa, Luisa Escobar-Hoyos, Kimberly Johung, Christina Wiess, Erik Spickard, Vasily N. Aushev, George Laliotis, Adham Jurdi, Minetta C. Liu, Jill Lacy. A phase II study of peri-operative modified FOLFIRINOX in localized pancreatic ductal adenocarcinoma (PDAC) [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr A002.

Does CT overestimate extra-pancreatic perineural invasion in patients with pancreatic ductal adenocarcinoma following neoadjuvant chemoradiation therapy?

To evaluate the diagnostic performance of CT in the assessment of extra-pancreatic perineural invasion (EPNI) in patients with pancreatic ductal adenocarcinoma (PDAC). This retrospective study included 123 patients (66 men; median age, 66 years) with PDAC who underwent radical surgery and pancreatic protocol CT for assessing surgical resectability between September 2011 and March 2019. Among the 123 patients, 97 patients had received neoadjuvant chemoradiation therapy (CRT). Two radiologists reviewed the CT images for evidence of EPNI using a 5-point scale (5 = definitely present, 4 = probably present, 3 = equivocally present, 2 = probably absent, and 1 = definitely absent). Diagnostic performance for assessing EPNI was evaluated with receiver operating characteristic (ROC) curve analysis. The sensitivity, specificity, and area under the ROC curve for assessing EPNI were 98%, 30%, and 0.62 in all patients; 97%, 22%, and 0.59 in patients with neoadjuvant CRT; and 100%, 100%, and 1.00 in patients without neoadjuvant CRT, respectively. False-positive assessment of EPNI occurred in 23% of patients (n = 28/123), and 100% of these (n = 28/28) had received neoadjuvant CRT. There was moderate to substantial agreement between the readers (ĸ = 0.49-0.62). Pancreatic protocol CT has better diagnostic performance for determination of EPNI in treatment naïve patients with PDAC and overestimation of EPNI is likely in patients who have received preoperative CRT. Pancreatic protocol CT has better diagnostic performance for the detection of EPNI in treatment naïve patients compared to patients receiving neoadjuvant CRT.

Deep-learning image reconstruction for 80-kVp pancreatic CT protocol: Comparison of image quality and pancreatic ductal adenocarcinoma visibility with hybrid-iterative reconstruction

PurposeTo evaluate the image quality and visibility of pancreatic ductal adenocarcinoma (PDAC) in 80-kVp pancreatic CT protocol and compare them between hybrid-iterative reconstruction (IR) and deep-learning image reconstruction (DLIR) algorithms. MethodA total of 56 patients who underwent 80-kVp pancreatic protocol CT for pancreatic disease evaluation from January 2022 to July 2022 were included in this retrospective study. Among them, 20 PDACs were observed. The CT raw data were reconstructed using 40% adaptive statistical IR-Veo (hybrid-IR group) and DLIR at medium- and high-strength levels (DLIR-M and DLIR-H groups, respectively). The CT attenuation of the abdominal aorta, pancreas, and PDAC (if present) at the pancreatic phase and those of the portal vein and liver at the portal venous phase; background noise; signal-to-noise ratio (SNR) of these anatomical structures; and tumor-to-pancreas contrast-to-noise ratio (CNR) were calculated. The confidence scores for the image noise, overall image quality, and visibility of PDAC were qualitatively assigned using a five-point scale. Quantitative and qualitative parameters were compared among the three groups using Friedman test. ResultsThe CT attenuation of all anatomical structures were comparable among the three groups (P = .26–.86), except that of the pancreas (P = .001). Background noise was lower (P <.001) and SNRs (P <.001) and tumor-to-pancreas CNR (P <.001) were higher in the DLIR-H group than those in the other two groups. The image noise, overall image quality, and visibility of PDAC were better in the DLIR-H group than in the other two groups (P <.001–.003). ConclusionIn 80-kVp pancreatic CT protocol, DLIR at a high-strength level improved image quality and visibility of PDAC.

MRI vs. CT for pancreatic adenocarcinoma vascular invasion: comparative diagnostic test accuracy systematic review and meta-analysis.

To perform a systematic review comparing the diagnostic accuracy of MRI vs. CT for assessing pancreatic ductal adenocarcinoma (PDAC) vascular invasion. MEDLINE, EMBASE, Cochrane Central, and Scopus were searched until December 2021 for diagnostic accuracy studies comparing MRI vs. CT to evaluate vascular invasion of pathologically confirmed PDAC in the same patients. Findings on resection or exploratory laparotomy were the preferred reference standard. Data extraction, risk of bias, and applicability assessment were performed by two authors using the Quality Assessment of Diagnostic Accuracy Studies-Comparative Tool. Bivariate random-effects meta-analysis and meta-regression were performed with 95% confidence intervals (95% CI). Three studies were included assessing 474 vessels without vascular invasion and 65 with vascular invasion in 107 patients. All patients were imaged using MRI at ≥ 1.5T and a pancreatic protocol CT. No difference was shown between MRI and CT for diagnosing PDAC vascular invasion: MRI/CT sensitivity (95% CI) were 71% (47-87%)/74% (56-86%), and specificity were 97% (94-99%)/97% (94-98%). Sources of bias included selection bias from only a subset of CT patients undergoing MRI and verification bias from patients with unresectable disease not confirmed on surgery. No patients received neoadjuvant therapy prior to staging. Based on limited data, no difference was observed between MRI and pancreatic protocol CT for PDAC vascular invasion assessment. MRI may be an adequate substitute for pancreatic protocol CT in some patients, particularly those who have already had a single-phase CT. Larger and more recent cohort studies at low risk of bias, including patients who have received neoadjuvant therapy, are needed. Abdominal MRI performed similarly to pancreatic protocol CT at assessing pancreatic ductal adenocarcinoma vascular invasion, suggesting local staging is adequate in some patients using MRI. More data are needed using larger, more recent cohorts including patients with neoadjuvant treatment. • Based on limited data, no difference was found between MRI and pancreatic protocol CT sensitivity and specificity for diagnosing PDAC vascular invasion (p = 0.81, 0.73 respectively). • Risk of bias could be reduced in future PDAC MRI vs CT comparative diagnostic test accuracy research by ensuring all enrolled patients undergo both imaging modalities being compared in random order and regardless of the findings on either modality. • More studies are needed that directly compare the diagnostic performance of MRI and CT for PDAC staging after neoadjuvant therapy.

Comparison of image quality and pancreatic ductal adenocarcinoma conspicuity between the low-kVp and dual-energy CT reconstructed with deep-learning image reconstruction algorithm

PurposeTo compare the image quality and conspicuity of pancreatic ductal adenocarcinoma (PDAC) between the low-kVp and dual-energy pancreatic protocol CT reconstructed with deep-learning image reconstruction (DLIR). MethodA cohort of 111 consecutive patients (median age, 72 years; 56 men) undergoing a pancreatic protocol CT were retrospectively analyzed. Among them, 58 patients underwent 80-kVp CT (80-kVp group), and 53 patients underwent dual-energy CT and reconstructed at 40-keV (40-keV group). The medium-strength level of DLIR were used in both groups. Quantitative measurements, qualitative image quality, PDAC conspicuity, and dose-length product (DLP) were compared between the two groups using Mann–Whitney U test. ResultsA total of 20 and 16 PDACs were found in the 80-kVp and 40-keV groups, respectively. CT numbers of the vasculatures and parenchymal organs (P <.001 for all) and the background noise at both pancreatic and portal venous phases (P <.001) were higher in the 40-keV group than in the 80-kVp group. The signal-to-noise ratio (SNR) of all anatomical structures (P <.001–0.005), except for the liver in reviewer 2 (P =.47), and the tumor-to-pancreas contrast-to-noise ratio (CNR; P <.001–0.01) were higher in the 40-keV group than in the 80-kVp group. No difference was found in the image quality at both phases (P =.30–0.90). PDAC conspicuity was better in the 40-keV group than in the 80-kVp group (P =.007–0.03). DLP at pancreatic (275 vs. 313 mGy*cm; P =.05) and portal venous phases (743 vs. 766 mGy*cm; P =.20) was comparable between the two groups. ConclusionUnder the same DLP, virtual monoenergetic images at 40-keV demonstrated higher SNR and tumor-to-pancreas CNR and better PDAC conspicuity compared to the 80-kVp setting.

Vascular involvement and resectability of pancreatic ductal adenocarcinoma on contrast-enhanced MRI: comparison with pancreatic protocol CT.

To compare the diagnostic performance for detecting vascular involvement and determining resectability differences regarding pancreatic ductal adenocarcinoma (PDAC) between contrast-enhanced CT and MRI. This retrospective study evaluated 82 patients (73years, 46 men) with PDAC who underwent both preoperative contrast-enhanced CT and MRI from January 2008 to March 2021. Two radiologists independently categorized vascular involvements for celiac, superior mesenteric, splenic, and common hepatic arteries, and portal, superior mesenteric, and splenic veins into no tumor contact, solid soft-tissue contact ≤ 180°, or solid soft-tissue contact > 180°. The radiologists also classified resectability into resectable, borderline resectable, or locally advanced. Receiver-operating-characteristic (ROC) analysis was conducted to evaluate the diagnostic performances for detecting vascular involvements which were confirmed by pathological or intraoperative findings. The proportion of resectability classifications was compared between CT and MRI by the Fisher's exact test. No statistical difference was found in the diagnostic performances for detecting vascular involvement in CT (area under the ROC curve [AUC], 0.50-0.89) and MRI (AUC, 0.51-0.75) (P = 0.06-> 0.99). Resectability on CT were 79% and 68%, 20% and 26%, and 1% and 6% for resectable, borderline resectable, and locally advanced tumors for reviewers 1 and 2; those on MRI were 87% and 81%, 12% and 13%, and 1% and 6%, respectively. The proportion of resectability classificationswas not different between CT and MRI (P = 0.48 and = 0.15 for reviewers 1 and 2, respectively). The diagnostic performance for detecting vascular involvement and determining resectability of PDAC on contrast-enhanced MRI were comparable with pancreatic protocol CT.

Multifocal pancreatic PPoma in the setting of MEN1: Case report and review of literature.

Introduction and importanceFunctioning pancreatic neuroendocrine tumors (pNETs) that express pancreatic polypeptide—PPomas—do not yet have a pathognomonic clinical syndrome associated with them due to their overall rarity and diverse symptoms. Moreover, in patients with MEN1, the often multifocal nature of pNETs presents a unique clinical issue.Case presentationWe report a case of a 22-year-old man with a known MEN1 gene mutation who was suffering from severe diarrhea (7–8 bowel movements per day) and was found to have only elevated PP levels on biochemical work-up. Ga68-DOTATATE PET/CT showed multifocal tumors in the body and tail of the pancreas that were not evident on contrast-enhanced CT. The patient underwent a successful laparoscopic radical antegrade modular pancreatosplenectomy (RAMP) and recovered well post-operatively with complete resolution of his diarrhea. Immunohistochemistry showed multiple pure PPomas.Clinical discussionThis case highlights the unique propensity for multifocal disease in patients with MEN1 mutations and the utility of functional imaging by somatostatin analogs, i.e., Ga68-DOTATATE PET/CT, in order to perform oncologic laparoscopic pancreatic resections.ConclusionPPomas in the setting of MEN1 mutations are a unique clinical entity due to their diverse associated clinical syndromes and propensity for multifocal disease.

Metastatic Insulinoma Presenting After Bariatric Surgery in a Patient Subsequently Diagnosed With MEN 1

Background: Hypoglycemia is a recognized complication of bariatric procedures due to changes in the gut hormonal milieu. Possible causes of hypoglycemia include dumping syndrome, nesidioblastosis and rarely insulinoma. MEN1 is a heritable disorder characterized by the occurrence of parathyroid, anterior pituitary and pancreatic islet cell tumors. Clinical Case: A 48 yo female with HTN, depression, PCOS, primary hyperparathyroidism s/p 3.5 gland parathyroidectomy 2008, facial angiofibroma 2011, obesity s/p gastric sleeve 2018, and a history of DMT2 presented with frequent episodes of hypoglycemia. DMT2 was diagnosed in 2003, but all DM drugs were withdrawn shortly after sleeve gastrectomy. One year after surgery, she started to develop primarily fasting hypoglycemia in the 40-50 mg/dl range confirmed on CGM. Symptoms included perioral numbness, diaphoresis and confusion which resolved with glucose tablets. She reported a 7 kg weight regain due to eating every 2 hours to minimize episodes but symptoms progressed. Family history was significant for HTN and DM. A 72 hour fast confirmed hyperinsulinemia with symptomatic hypoglycemia at a serum glucose of 37 mg/dl, a suppressed ß-hydroxybutyrate of 0.6 mmol/L, elevated proinsulin 7.7 ρmol/L and inappropriate normal c-peptide 0.8 ng/mL. The oral hypoglycemic panel was negative. A pancreatic protocol CT revealed a 1.2 cm heterogeneous arterial enhancing lesion in the body of pancreas, a 0.6 cm focus in the tail of pancreas, a 1.6 cm enhancing lesion in the liver and a 1.4 cm abdominal wall mass. Genetic testing was positive for MEN-1 and additional biochemical evaluation including VIP, gastrin and glucagon was negative. A pituitary MRI was unremarkable. She underwent an ex-lap, partial hepatectomy, distal pancreatectomy, splenectomy, and resection of the duodenal mass. The pancreas had multiple NETs, largest was 1.6 cm and stained positive for insulin. The liver mass demonstrated a metastatic well differentiated NET. The 1.7 cm duodenal mass was consistent with a leiomyoma. All surgical margins were negative, but focal lymphovascular and perineural invasion was identified with negative lymph nodes (0/27). She was diagnosed with a metastatic insulinoma with histopathology revealing a well differentiated neuroendocrine tumor G1, <1mitosis/2mm2, Ki-67 less than 3%, stage pT1N0M1. Hypoglycemia resolved post-operatively. Conclusion: Hypoglycemia predominantly in the fasting state, worsening shortly after bariatric surgery, or refractory to dietary or medical management should be further evaluated to exclude insulinoma. Given her medical history, there was concern for MEN-1, thus prompting genetic testing. Unlike with sporadic cases, there is a higher rate of recurrence with MEN-1 associated insulinoma. Highly unusual is also the finding of metastatic disease, occurring only in 4- 14% of all insulinoma cases.

Low keV portal venous phase as a surrogate for pancreatic phase in a pancreatic protocol dual-energy CT: feasibility, image quality, and lesion conspicuity.

To assess the feasibility of a proposed pancreatic protocol CT generated from portal-venous phase (PVP) dual-energy CT (DECT) acquisition and its impact on image quality, lesion conspicuity, and arterial visualization/involvement. We included 111 patients (mean age, 66.8 years) who underwent pancreatic protocol DECT (pancreatic phase, PP, and PVP). The original DECT acquisition was used to create two data sets-standard protocol (50 keV PP/65 keV PVP) and proposed protocol (40 keV/65 keV PVP). Three reviewers evaluated the two data sets for image quality, lesion conspicuity, and arterial visualization/involvement using a 5-point scale. The signal-to-noise ratio (SNR) of pancreas and lesion-to-pancreas contrast-to-noise ratio (CNR) was calculated. Qualitative scores, quantitative parameters, and dose-length product (DLP) were compared between standard and proposed protocols. The image quality, SNR of pancreas, and lesion-to-pancreas CNR of the standard and proposed protocol were comparable (p = 0.11-1.00). Lesion conspicuity was comparable between the standard and proposed protocols for pancreatic ductal adenocarcinoma (p = 0.55) and pancreatic cysts (p = 0.28). The visualization of larger arteries and arterial involvement were comparable between the two protocols (p = 0.056-1.00) while the scores were higher for smaller vessels in the standard protocol (p < 0.0001-0.0015). DLP of the proposed protocol (670.4 mGy·cm) showed a projected 42% reduction than the standard protocol (1145.9 mGy·cm) (p < 0.0001). Pancreatic protocol CT generated from a single PVP DECT acquisition is feasible and could potentially be an alternative to the standard pancreatic protocol with PP and PVP. • The lesion conspicuity for focal pancreatic lesions was comparable between the proposed protocol and standard dual-phase pancreatic protocol CT. • Qualitative and quantitative image assessments were almost comparable between two protocols. • The radiation dose of a proposed protocol showed a projected 42% reduction from the conventional protocol.

Simulated twin-phase pancreatic CT generated using single portal venous phase dual-energy CT acquisition in pancreatic ductal adenocarcinoma.

To evaluate the diagnostic performance of a simulated twin-phase pancreatic protocol CT generated from a single portal venous phase (PVP) dual-energy CT (DECT) acquisition in patients with pancreatic ductal adenocarcinoma (PDAC). In this retrospective study, we included 63 patients with PDAC who underwent pancreatic protocol (pancreatic phase [PP] and PVP) DECT. Two data sets were created from this original acquisition-(1) Standard protocol (50keV PP/65keV PVP) and (2) Simulated protocol (40keV/65keV PVP). Using a 5-point scale, three readers scored image quality, tumor conspicuity, and arterial involvement by the PDAC. Signal-to-noise ratio (SNR) of the pancreas and tumor-to-pancreas contrast-to-noise ratio (CNR) were calculated. Qualitative scores, quantitative parameters, and radiation dose were compared between standard and simulated protocols. No significant difference in detection rate of PDAC was seen between the standard (58/63, 92.1%) and simulated protocols (56/63, 88.9%) (P = 0.76). Subjective scoring for arterial involvement for celiac (P = 0.86), superior mesenteric (P = 0.88), splenic (P = 0.86), common hepatic (P = 0.52), gastroduodenal (P = 0.95), first jejunal (P = 0.48) arteries, and aorta (P = 1.00) were comparable between two protocols. The image quality (P = 0.14), the SNR of the pancreas (P = 0.15), and CNR (P = 0.54) were comparable between two protocols. The projected mean dose-length product (DLP) (629.6 ± 148.3mGy cm) in the simulated protocol showed a 44% reduction in radiation dose compared to the standard protocol (mean DLP, 1123.3 ± 268.9mGy cm) (P < 0.0001). Low keV images generated from a PVP DECT acquisition allows creation of a twin-phase pancreatic protocol CT with comparable diagnostic accuracy for detecting PDAC with significant reduction in radiation dose. Reduced radiation dose is desirable in surveillance and screening for pancreatic diseases.

Patterns and quality of care for patients diagnosed with pancreatic cancer in Victoria, Australia from 2016 - 2018

Introduction: A core set of quality indicators (QIs) was developed in 2017 using a modified Delphi approach to monitor quality of care, and optimise quality of life and survival in patients diagnosed with pancreatic cancer (PC). This study (1) describes the patterns of care based on disease stage at diagnosis and (2) assesses the association between meeting the QI and survival. Methods: Data were collected from hospitals and consulting rooms for patients recruited to the Upper Gastrointestinal Cancer Registry (UGICR). Associations between 23 QIs and patient and health service characteristics were tested using linear regression and survival analysed using Kaplan-Meier and Cox proportional hazards models. Results: A total of 871 patients were eligible for this study with 52% male, 74% over the age of 65 27% potentially resectable and 47% with metastatic disease at diagnosis. A third of patients had no known treatment, and 56% received treatment according to their operability at diagnosis (Figure 1). Half the patients were deceased within 6 months from diagnosis. Meeting the following QIs was associated with improved patient survival at 6 months (1) imaging using a pancreatic protocol CT or MRI (OR=3.1, 95% CI=2.2 - 4.4); (2) documentation of performance status (ECOG or ASA) at presentation (OR=2.1, 95% CI=1.5 - 2.9); (3) disease management discussion at a multidisciplinary team meeting (OR=6.4, 95% CI=4.3 - 9.6) and (4) being included in a clinical trial (OR=5.0, 95% CI=2.7 - 9.1). Conclusion: Adherence to QIs can optimise care and may improve survival in PC.

4532 Pancreatic Cyst Risk Stratification for Early Detection of Pancreatic Cancer Using Quantitative Radiomics and Activity-Based Biomarkers

OBJECTIVES/GOALS: Pancreatic cysts are comprised of both precancerous mucinous lesions and non-mucinous lesions with minimal malignant potential. Our goal is to improve our ability to classify the type of cyst using a combination of novel radiomic features and cyst fluid proteolytic activity. METHODS/STUDY POPULATION: Preoperative pancreatic protocol CT images from 30 patients with proteolytic assay characterization, followed by surgical resection with a pathologically confirmed pancreatic cyst diagnosis between 2016-2019 will be used in this study. We will contour images using the widely available software 3D Slicer, and extract radiomic features using IBEX software. We will analyze area under the ROC curves to identify the radiomic features that best differentiate mucinous from non-mucinous cysts, and identify features to be cross validated. The predictive ability of identified radiomic features combined with proteolytic assay will be determined by performing multiple logistic regression analysis and comparing AUROC analysis. We will determine sensitivity and specificity for individual, as well as combinations of, analytes to determine the optimal classifier. RESULTS/ANTICIPATED RESULTS: We anticipate that the predictive ability, sensitivity, and specificity of utilizing radiomic features combined with proteolytic assay data will exceed the performance of any individual test. DISCUSSION/SIGNIFICANCE OF IMPACT: This work is designed to provide a predictive radiomic model that will enable us to better identify mucinous cysts that require further evaluation, and potentially prevent unnecessary surgery in other patients. Ultimately, we would like to improve the accuracy of noninvasive radiographic evaluation using radiomic markers. CONFLICT OF INTEREST DESCRIPTION: Dr. Charles Craik is a co-founder of Alaunus Biosciences, Inc.

Neuroendocrine tumor of Pancreas: Which modality is better, 320-MDCT or 3T-MRI?

Background: Significant improvement in the spatial and temporal resolution of CT have been made over the past decade, with advent of multidetector row CT (MDCT). Also, the increased spatial resolution of the 3T-MRI allows for high-quality abdominal imaging. Therefore, neuroendocrine tumors of pancreas (PNET) and their metastasis are increasingly diagnosed on imaging studied performed for unrelated purposes. Our purpose of this study is to find out the good modality to detect PNETs. Material and Methods: We selected 11 PNETs. Four of the 11 PNETs were diagnosed as NET G2, and seven of the 11 PNETs were diagnosed as NET G1. We took both 320-MDCT and 3T-MRI for all patients before surgery. We used pancreatic protocol CT with and without intravenous contrast. We made 5 kind of CT image such as non-contrast image, early-arterial phase (25sec), late-arterial phase (40sec), portal phase (70sec) and venous phase(180sec). All CT slices were made of 1mm. About 3T-MRI, we selected 2 kind of images, diffusion-weighted image (DWI) and T2 weighted image (T2WI). Slice thickness of both DWI and T2 weighted image was 3mm. We compared CT image with DWI and T2WI. Results: Seven of the 11 PNETS were diagnosed on both CT, DWI and T2WI. All 7 PNETs showed well-enhanced on late-arterial phase on CT and high signal intensity on both DWI and T2WI. Three of the 11 PNETs were able to detect on CT and DWI. All 3 PNET showed iso-signal intensity as compared to the normal pancreas. One of the 11 PNET was able to detect on DWI and T2WI. The PNET showed the same enhancement as the normal pancreatic parenchyma on all phase CT. Conclusion: DWI was the most sensitive image to detect PNET. High cell density PNETs with moderate vascularity may show atypical PNETs on CT and MRI.

1350 Small Pancreatic Cyst Progressed to Metastatic Pancreatic Neuroendocrine Tumor in Three Months

INTRODUCTION: We report a case of an incidentally found asymptomatic pancreatic tail cyst that rapidly grew from 1 cm to 3.4 cm in a 3-month period. The final diagnosis is metastatic pancreatic neuroendocrine tumor (NET). CASE DESCRIPTION/METHODS: A 72-year-old male was referred for EUS to evaluate an incidental 13 mm pancreatic tail cyst found on CT chest. He was asymptomatic and had no prior history of pancreatitis or family history of pancreatic cancer. EUS showed a 10 mm microcystic lesion in the pancreatic tail with a central echogenic area suggestive of a serous cystadenoma (Figure 1a). CT performed three months later for follow up on lung nodules demonstrated interval enlargement of the pancreatic lesion to 3.4 cm. The lesion appeared isodense and solid. EUS confirmed the rapid increase of size from 1 to 3 cm (Figure 1b). FNA was performed and cytology was interpreted as malignant cells derived from adenocarcinoma. Serum CA 19-9 was 1.88 U/ml. Pancreatic protocol CT (Figure 2) found a new 4 cm low-attenuation liver lesion within segment IV B. Biopsy of the liver lesion was negative for neoplasm. Patient was referred to surgery and the plan was to perform laparoscopy, excisional wedge liver biopsy, followed by distal pancreatectomy and splenectomy if the wedge biopsy did not show metastatic adenocarcinoma. Intraoperatively, a very small subcapsular lesion was excised from the liver and sent for frozen section to pathology. By the time pathology came back reporting a 2.5 mm lesion with evidence of poorly differentiated carcinoma, the surgeon has already transected the splenic artery. Therefore, distal pancreatectomy and splenectomy were completed. Final pathology reported grade 3 well differentiated NET of distal pancreas with metastasis involving 1/13 LNs and liver, negative margins achieved. Ki-67 labeling index was 75% (Figure 3). Patient has had no sign of cancer progression six months after the initial diagnosis. DISCUSSION: Our interesting case raises many important points to consider; Pancreatic NET can uncommonly have a cystic component. Additionally, pancreatic NET can mimic pancreatic adenocarcinoma and cytology alone cannot reliably differentiate between high grade neuroendocrine tumors and adenocarcinoma. This patient could have been erroneously treated for metastatic adenocarcinoma. Endosonographers should be alert to this possibility when a presentation is not typical for adenocarcinoma and/or the lesion has cystic components with a smooth border.

2627 Small Bowel Adenocarcinoma With Right Atrial Metastasis: A Case Combining Two Rare Entities

INTRODUCTION: Small bowel adenocarcinoma comprises less than 2% of all gastrointestinal malignancies. Given its rarity, little is known about its clinical features, treatment modalities, or prognosis. Early diagnosis remains a challenge due to the absence or nonspecific nature of its symptoms. The heart is a rare site for metastasis of any malignancy, and cardiac metastases are likewise often clinically silent. Here we present a case of jejunal adenocarcinoma with metastasis to the heart that was ultimately diagnosed by pancreatic protocol CT imaging. CASE DESCRIPTION/METHODS: An 82-year-old female with a history of atrial fibrillation presented with a left middle cerebral artery stroke after her warfarin was held due to iron deficiency anemia. She underwent successful thrombectomy, but her initial evaluation with a transthoracic echocardiogram incidentally revealed a 4 cm × 3.9 cm right atrial mass. Further evaluation with a cardiac MRI and a standard CT of the chest/abdomen/pelvis showed a large hypoattenuating mass in the right atrium that extended into the inferior IVC and left hepatic vein; no tumor primary was identified. Cardiac biopsy found a moderately differentiated adenocarcinoma positive for CK-20 and CDX-2, suggesting a GI origin. She then underwent an EGD and colonoscopy, neither of which found evidence of a malignancy, although the EGD noted a prominent ampulla with normal biopsies. Given this finding and the presence of an adenocarcinoma of unknown origin, she was scheduled for an EUS and capsule endoscopy. However, before these procedures were performed, a CT with pancreas protocol revealed a 5 cm circumferential mass in the proximal jejunum causing low grade obstruction; the morphology was consistent with adenocarcinoma. The patient was treated with radiation therapy. DISCUSSION: To the best of our knowledge, this is the first case report of a small bowel adenocarcinoma metastatic to the heart. After the discovery of an atrial adenocarcinoma, a small bowel origin was not initially considered given its rarity and nonspecific presentation. The first CT scan may have failed to detect a jejunal primary for the same reason, although differences in contrast infusion technique may have played a role. Cardiac metastases are similarly very rare and have most often been reported in lung cancer, melanoma, lymphoma, breast cancer, sarcoma, and renal cell carcinoma. This case suggests that although rare, small bowel adenocarcinoma should be considered in patients found to have cardiac metastatic disease.

Enhancements in pancreatic protocol CT as a prognostic indicator in pancreatic cancer.

216 Background: Pancreatic protocol CT (pCT) is widely used to evaluate stage and resectability of pancreatic ductal adenocarcinoma (PDAC). Recent studies show that CT enhancement patterns are related to the patient’s prognosis in several cancers, however it is not well described that pCT enhancement has prognostic effect in resectable PDAC so far. We aimed to show correlaton between pCT enhancements and prognosis in resectable PDAC. Methods: We retrospectively enrolled 159 patients (median age, 67.8 years) who underwent pCT before curative resection in Seoul National University Bundang Hospital between January 2010 and December 2015, with final pathological diagnosis of PDAC. CT enhancement ratio (CTER) of each primary lesion was calculated as proportional difference between maximum Houndsfield Unit (HU) of pancreatic phase (PP) image and maximum HU of non-contrast image; [(max HU of PP) - (max HU of non-contrast)] / (max HU of non-contrast). Patients were classified into two groups, based on CTER. Kaplan–Meier analysis and Cox proportional hazards models were used to correlate CTER with overall survival (OS) and recurrence free survival (RFS). Results: Median overall survival was 22.0 months during a median follow-up period of 18.5 months. Based on CTER with cut-off value of 1.8, higher (CTER ≥ 1.8) group (N = 43) was compared with lower (CTER &lt; 1.8) group (N = 116) in terms of OS and RFS. Lower group showed significantly shorter median OS (18.5 months versus 39.3 months, P &lt; 0.001) and median RFS (9.9 months versus 21.5 months, P = 0.006) than those of higher group. Multivariate regression analysis showed that lower group had shorter OS (HR 1.70; CI 1.01-2.85, P = 0.044) and RFS (HR 1.84; CI 1.10-3.06, P = 0.019). Conclusions: Our study suggests that lower enhancement in pancreatic phase of pCT is related to poor prognosis in PDAC. Therefore, active surveillance would be required in resected PDAC patients with CTER less than 1.8.

Neoadjuvant FOLFIRINOX and IMRT concurrent with FDR-gemcitabine in patients with borderline resectable pancreatic cancer (BRPC).

381 Background: Preoperative therapy in BRPC is intended to increase the likelihood of R0 resection although an optimal regimen is yet to be defined. Methods: Patients (pts) with BRPC (NCCNv.2.2010 guidelines) and ECOG PS 0-1 were enrolled in a single-institution, phase II trial (NCT01661088). Pts received FOLFIRINOX x 6, followed by IMRT (50 Gy in 25 fractions) concurrent with FDR-gemcitabine 1 g/m2 on days 1, 8, 22, 29. Two additional FDR-gemcitabine infusions completed pre-operative treatment. Pancreatic protocol CT scans (dual phase, 0.65 mm slices) were performed after 4 infusions of FOLFIRINOX, 3 weeks after IMRT, and at treatment completion. Pts without distant disease were offered surgical exploration. The primary objective was to determine R0 resection rate. Secondary objectives included progression free survival (PFS), overall survival (OS), response rate and safety. Results: A total of 25 pts (64% men) median age 60 years (range 47-77) were enrolled from 11/2011 through 01/2017. Twenty-one (84%) pts completed FOLFIRINOX and 19 (76%) all protocol therapy. Treatment-related grade 3-4 adverse events ( &gt; 10%) included neutropenia (40%), nausea/vomiting (28%), diarrhea (16%) and fatigue (12%). One early death and 1 discontinuation due to toxicity occurred during FOLFIRINOX. Response to pre-op therapy included 11 PR, 9 SD, 3 PD and 2 NE. Of 25 treated pts, 18 (72%) had laparotomy and 13 (52%) underwent resection (all R0). The median PFS and OS were 18.1 (95% CI, 10.6 to 25.1) and 24.2 (95% CI, 12.6 to 40.0) months, respectively. The median OS for R0 resected pts was 37.1 (95% CI, 15.4 – not reached) months. Conclusions: Neoadjuvant therapy with FOLFIRINOX, followed by IMRT with concurrent FDR-gemcitabine in BRPC is feasible and tolerated. While R0 resection rate was not obviously improved, OS of the entire cohort and especially in R0 resected pts was favorable. Clinical trial information: NCT01661088.

Multi-institutional survey on imaging practice patterns in pancreatic ductal adenocarcinoma.

To study the practice patterns for performance and interpretation of CT/MRI imaging studies in patients with pancreatic ductal adenocarcinoma (PDAC) at multiple institutions using a survey-based assessment. In this study, abdominal radiologists/body imagers on the Society of Abdominal Radiology disease-focused panel for PDAC and from multiple institutions participated in an online survey. The survey was designed to investigate the imaging and reporting practice patterns for PDAC. The survey questionnaire addressed the experience of referring providers, choice of imaging modality for diagnosis and follow-up of PDAC, structured imaging templates utilization for PDAC, and experiences with the use of structured reports. The response rate was 89.6% (43/48), with majority of the respondents working in a teaching hospital or academic research center (95.4%). While 86% of radiologists reported use of structured reporting templates in their practice, only 60.5% used standardized templates specific to PDAC. This lower percentage was despite most of them (77%) being aware of existence of PDAC-specific templates and recognizing their benefits, such as preference by referring providers (83%), improved uniformity (100%), and higher accuracy of reports (76.2%). The common impediments to the use of PDAC-specific templates were interference with efficient workflow (67.5%), lack of interest (52.5%), and complexity of existing templates (47.5%). With regards to imaging practice, 92.7%(n=40/43) of respondents reported performing dynamic multiphasic pancreatic protocol CT for evaluation of patients withinitial suspicion or staging of PDAC. Structured reporting templates for PDAC are not universally utilized in subspecialty abdominal/body imaging practices due to concerns of interference with efficient workflow and complexity of templates. Multiphasic pancreatic protocol CT is most frequently performed for evaluation of PDAC.

Interventional endoscopy in the diagnosis and management of pancreatic adenocarcinoma.

Pancreatic cancer accounts for approximately 3% of all cancers in US, and is the fourth leading cause of mortality in both men and women. It is a silent killer due to lack of early symptoms and the majority of patients present at advanced stage at the time of initial diagnosis. Only 15-20% of patients are candidates for curative resection and even then, the 5-year survival rates range from 10-25%. Despite recent advances in the treatment of advanced pancreatic cancer, the prognosis remains grim with 5-year overall survival (OS) of approximately 10%. Early detection is key for improving patient outcomes in this lethal disease. Contributing to the difficulty in the diagnosis and management is the anatomic location of the pancreas within the abdomen (retroperitoneal location and being adjacent to hollow viscus, solid organs and major vessels), and suboptimal response to systemic chemotherapy. Multimodality imaging (pancreatic protocol CT and MRI/MRCP) is often used for the diagnosis and staging of pancreatic adenocarcinoma. Interventional endoscopy is a relatively new field, and with Endoscopic techniques becoming more advanced, their role in diagnosis and management of pancreatic cancer is expanding rapidly. Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) are the two main modalities used in cases of pancreatic neoplasms.