Artificial intelligence for assessment of vascular involvement and tumor resectability on CT in patients with pancreatic cancer.

OBJECTIVE: This study aimed to develop and evaluate an automatic model using artificial intelligence (AI) for quantifying vascular involvement and classifying tumor resectability stage in patients with pancreatic ductal adenocarcinoma (PDAC), primarily to support radiologists in referral centers. Resectability of PDAC is determined by the degree of vascular involvement on computed tomography scans (CTs), which is associated with considerable inter-observer variability. METHODS: We developed a semisupervised machine learning segmentation model to segment the PDAC and surrounding vasculature using 613 CTs of 467 patients with pancreatic tumors and 50 control patients. After segmenting the relevant structures, our model quantifies vascular involvement by measuring the degree of the vessel wall that is in contact with the tumor using AI-segmented CTs. Based on these measurements, the model classifies the resectability stage using the Dutch Pancreatic Cancer Group criteria as either resectable, borderline resectable, or locally advanced (LA). RESULTS: We evaluated the performance of the model using a test set containing 60 CTs from 60 patients, consisting of 20 resectable, 20 borderline resectable, and 20 locally advanced cases, by comparing the automated analysis obtained from the model to expert visual vascular involvement assessments. The model concurred with the radiologists on 227/300 (76%) vessels for determining vascular involvement. The model's resectability classification agreed with the radiologists on 17/20 (85%) resectable, 16/20 (80%) for borderline resectable, and 15/20 (75%) for locally advanced cases. CONCLUSIONS: This study demonstrates that an AI model may allow automatic quantification of vascular involvement and classification of resectability for PDAC. RELEVANCE STATEMENT: This AI model enables automated vascular involvement quantification and resectability classification for pancreatic cancer, aiding radiologists in treatment decisions, and potentially improving patient outcomes. KEY POINTS: • High inter-observer variability exists in determining vascular involvement and resectability for PDAC. • Artificial intelligence accurately quantifies vascular involvement and classifies resectability for PDAC. • Artificial intelligence can aid radiologists by automating vascular involvement and resectability assessments.

MR Elastography of the Pancreas: Bowel Preparation and Repeatability Assessment in Pancreatic Cancer Patients and Healthy Controls.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) stromal viscoelasticity can be measured using MR elastography (MRE). Bowel preparation regimens could affect MRE quality and knowledge on repeatability is crucial for clinical implementation. PURPOSE: To assess effects of four bowel preparation regimens on MRE quality and to evaluate repeatability and differentiate patients from healthy controls. STUDY TYPE: Prospective. POPULATION: 15 controls (41 ± 16 years; 47% female), 16 PDAC patients (one excluded, 66 ± 12 years; 40% female) with 15 age-/sex-matched controls (65 ± 11 years; 40% female). Final sample size was 25 controls and 15 PDAC. FIELD STRENGTH/SEQUENCE: 3-T, spin-echo echo-planar-imaging, turbo spin-echo, and fast field echo gradient-echo. ASSESSMENT: Four different regimens were used: fasting; scopolaminebutyl; drinking 0.5 L water; combination of 0.5 L water and scopolaminebutyl. MRE signal-to-noise ratio (SNR) was compared between all regimens. MRE repeatability (test-retest) and differences in shear wave speed (SWS) and phase angle (ϕ) were assessed in PDAC and controls. Regions-of-interest were defined for tumor, nontumorous (n = 8) tissue in PDAC, and whole pancreas in controls. Two radiologists delineated tumors twice for evaluation of intraobserver and interobserver variability. STATISTICAL TESTS: Repeated measures analysis of variance, coefficients of variation (CoVs), Bland-Altman analysis, (un)paired t-test, Mann-Whitney U-test, and Wilcoxon signed-rank test. P-value<0.05 was considered statistically significant. RESULTS: Preparation regimens did not significantly influence MRE-SNR. Therefore, the least burdensome preparation (fasting only) was continued. CoVs for tumor SWS were: intrasession (12.8%) and intersession (21.7%), and intraobserver (7.9%) and interobserver (10.3%) comparisons. For controls, CoVs were intrasession (4.6%) and intersession (6.4%). Average SWS for tumor, nontumor, and healthy tissue were: 1.74 ± 0.58, 1.38 ± 0.27, and 1.18 ± 0.16 m/sec (ϕ: 1.02 ± 0.17, 0.91 ± 0.07, and 0.85 ± 0.08 rad), respectively. Significant differences were found between all groups, except for ϕ between healthy-nontumor (P = 0.094). DATA CONCLUSION: The proposed bowel preparation regimens may not influence MRE quality. MRE may be able to differentiate between healthy tissue-tumor and tumor-nontumor. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.

Radiomics preoperative-Fistula Risk Score (RAD-FRS) for pancreatoduodenectomy: development and external validation.

BACKGROUND: Accurately predicting the risk of clinically relevant postoperative pancreatic fistula after pancreatoduodenectomy before surgery may assist surgeons in making more informed treatment decisions and improved patient counselling. The aim was to evaluate the predictive accuracy of a radiomics-based preoperative-Fistula Risk Score (RAD-FRS) for clinically relevant postoperative pancreatic fistula. METHODS: Radiomic features were derived from preoperative CT scans from adult patients after pancreatoduodenectomy at a single centre in the Netherlands (Amsterdam, 2013-2018) to develop the radiomics-based preoperative-Fistula Risk Score. Extracted radiomic features were analysed with four machine learning classifiers. The model was externally validated in a single centre in Italy (Verona, 2020-2021). The radiomics-based preoperative-Fistula Risk Score was compared with the Fistula Risk Score and the updated alternative Fistula Risk Score. RESULTS: Overall, 359 patients underwent a pancreatoduodenectomy, of whom 89 (25 per cent) developed a clinically relevant postoperative pancreatic fistula. The radiomics-based preoperative-Fistula Risk Score model was developed using CT scans of 118 patients, of which three radiomic features were included in the random forest model, and externally validated in 57 patients. The model performed well with an area under the curve of 0.90 (95 per cent c.i. 0.71 to 0.99) and 0.81 (95 per cent c.i. 0.69 to 0.92) in the Amsterdam test set and Verona data set respectively. The radiomics-based preoperative-Fistula Risk Score performed similarly to the Fistula Risk Score (area under the curve 0.79) and updated alternative Fistula Risk Score (area under the curve 0.79). CONCLUSION: The radiomics-based preoperative-Fistula Risk Score, which uses only preoperative CT features, is a new and promising radiomics-based score that has the potential to be integrated with hospital CT report systems and improve patient counselling before surgery. The model with underlying code is readily available via www.pancreascalculator.com and www.github.com/PHAIR-Consortium/POPF-predictor.

Added value of 3T MRI and the MRI-halo sign in assessing resectability of locally advanced pancreatic cancer following induction chemotherapy (IMAGE-MRI): prospective pilot study.

BACKGROUND: Restaging of locally advanced pancreatic cancer (LAPC) after induction chemotherapy using contrast-enhanced computed tomography (CE-CT) imaging is imprecise in evaluating local tumor response. This study explored the value of 3 Tesla (3 T) contrast-enhanced (CE) and diffusion-weighted (DWI) magnetic resonance imaging (MRI) for local tumor restaging. METHODS: This is a prospective pilot study including 20 consecutive patients with LAPC with RECIST non-progressive disease on CE-CT after induction chemotherapy. Restaging CE-CT, CE-MRI, and DWI-MRI were retrospectively evaluated by two abdominal radiologists in consensus, scoring tumor size and vascular involvement. A halo sign was defined as replacement of solid perivascular (arterial and venous) tumor tissue by a zone of fatty-like signal intensity. RESULTS: Adequate MRI was obtained in 19 patients with LAPC after induction chemotherapy. Tumor diameter was non-significantly smaller on CE-MRI compared to CE-CT (26 mm vs. 30 mm; p = 0.073). An MRI-halo sign was seen on CE-MRI in 52.6% (n = 10/19), whereas a CT-halo sign was seen in 10.5% (n = 2/19) of patients (p = 0.016). An MRI-halo sign was not associated with resection rate (60.0% vs. 62.5%; p = 1.000). In the resection cohort, patients with an MRI-halo sign had a non-significant increased R0 resection rate as compared to patients without an MRI-halo sign (66.7% vs. 20.0%; p = 0.242). Positive and negative predictive values of the CE-MRI-halo sign for R0 resection were 66.7% and 66.7%, respectively. CONCLUSIONS: 3 T CE-MRI and the MRI-halo sign might be helpful to assess the effect of induction chemotherapy in patients with LAPC, but its diagnostic accuracy has to be evaluated in larger series.

Short- and long-term outcomes of selective use of Frey or extended lateral pancreaticojejunostomy in chronic pancreatitis.

BACKGROUND: Surgery is the most effective treatment in patients with painful chronic pancreatitis and a dilated pancreatic duct. Studies reporting the outcomes of selected surgical approach according to the pancreatic head size in these patients are lacking. METHOD: This was a retrospective, observational single-centre study of consecutive patients who underwent either a Frey procedure or extended lateral pancreaticojejunostomy (eLPJ) for pain due to chronic pancreatitis with a dilated main pancreatic duct (5 mm or more) between 2006 and 2017. A Frey procedure was used in patients with pancreatic head enlargement (40 mm or more) and eLPJ (full-length pancreaticojejunostomy, including transection of the gastroduodenal artery) in others. A biliodigestive bypass was added in the case of biliary obstruction. RESULTS: Overall, 140 of 220 patients met the eligibility criteria: 70 underwent a Frey procedure and 70 an eLPJ. Hepaticojejunostomy was added in 17.1 per cent of patients (Frey: 24.3 per cent; eLPJ: 10.0 per cent (P = 0.025)). Major morbidity occurred in 15.0 per cent of patients (Frey: 21.4 per cent; eLPJ: 8.6 per cent (P = 0.033)). After a median 7.8 years of follow-up, the mean (s.d.) decrease in Izbicki pain score was 33 (27) points (34 (28) points after a Frey procedure; 32 (26) points after an eLPJ). Pain relief was reported as 'very much' by 87.5 per cent of patients (Frey: 86.1 per cent; eLPJ: 88.9 per cent) and as 'partial' by 11.1 per cent (Frey: 13.8 per cent; eLPJ: 8.3 per cent). CONCLUSION: Selective-use of either a Frey procedure or eLPJ in patients with symptomatic chronic pancreatitis was-associated with low morbidity and long-term pain relief. Adding a-biliodigestive bypass did not increase morbidity.

Treatment strategies and clinical outcomes in consecutive patients with locally advanced pancreatic cancer: A multicenter prospective cohort.

INTRODUCTION: Since current studies on locally advanced pancreatic cancer (LAPC) mainly report from single, high-volume centers, it is unclear if outcomes can be translated to daily clinical practice. This study provides treatment strategies and clinical outcomes within a multicenter cohort of unselected patients with LAPC. MATERIALS AND METHODS: Consecutive patients with LAPC according to Dutch Pancreatic Cancer Group criteria, were prospectively included in 14 centers from April 2015 until December 2017. A centralized expert panel reviewed response according to RECIST v1.1 and potential surgical resectability. Primary outcome was median overall survival (mOS), stratified for primary treatment strategy. RESULTS: Overall, 422 patients were included, of whom 77% (n = 326) received chemotherapy. The majority started with FOLFIRINOX (77%, 252/326) with a median of six cycles (IQR 4-10). Gemcitabine monotherapy was given to 13% (41/326) of patients and nab-paclitaxel/gemcitabine to 10% (33/326), with a median of two (IQR 3-5) and three (IQR 3-5) cycles respectively. The mOS of the entire cohort was 10 months (95%CI 9-11). In patients treated with FOLFIRINOX, gemcitabine monotherapy, or nab-paclitaxel/gemcitabine, mOS was 14 (95%CI 13-15), 9 (95%CI 8-10), and 9 months (95%CI 8-10), respectively. A resection was performed in 13% (32/252) of patients after FOLFIRINOX, resulting in a mOS of 23 months (95%CI 12-34). CONCLUSION: This multicenter unselected cohort of patients with LAPC resulted in a 14 month mOS and a 13% resection rate after FOLFIRINOX. These data put previous results in perspective, enable us to inform patients with more accurate survival numbers and will support decision-making in clinical practice.

Evaluation of the modified Van Assche index for assessing response to anti-TNF therapy with MRI in perianal fistulizing Crohn's disease.

BACKGROUND: Structured evaluation of magnetic resonance imaging (MRI) is important to guide clinical decisions of perianal fistulas in Crohn's disease (CD) patients. PURPOSE: To evaluate the recently developed modified Van Assche index to assess clinical responses to anti-tumor necrosis factor (TNF) therapy in patients with perianal fistulizing CD. METHODS: A search of medical records identified patients with fistulizing perianal CD who underwent baseline and follow-up MRI while receiving anti-TNF treatment. Patients were divided into clinical responders and non-responders based on physician's assessment. MRI-scans were scored using the original and modified Van Assche index and scores between baseline and follow-up were compared within clinical responders and non-responders. RESULTS: Thirty cases were included (48% female, median age 27 years). Clinical responders (n = 16) had a median modified Van Assche score of 9.6 (IQR 5.8-12.7) at baseline and 5.8 (IQR 3.5-8.5) at follow-up (p = 0.008). In non-responders (n = 14), corresponding scores were 7.7 (IQR 5.8-13.5) and 8.2 (IQR 5.8-11.5) (p = 0.624). In clinical responders, 6/16 showed no drop in modified Van Assche score at follow-up. Scores obtained with the original Van Assche index dropped between baseline and follow-up in clinical responders (13.0 vs. 9.6, p = 0.011), whereas no decrease was observed in non-responders (11.5 vs. 11.5, p = 0.324). CONCLUSIONS: While the modified Van Assche index overall decreases significantly in patients with perianal fistulas responding to anti-TNF treatment, one third of responders had unaltered scores at follow-up. Also, outcomes were comparable to the original Van Assche index. Further optimization of the modified Van Assche index is needed before application in larger studies.

Added value of intra-operative ultrasound to determine the resectability of locally advanced pancreatic cancer following FOLFIRINOX chemotherapy (IMAGE): a prospective multicenter study.

BACKGROUND: Determining the resectability of locally advanced pancreatic cancer (LAPC) after FOLFIRINOX chemotherapy is challenging because CT-scans cannot reliably assess vascular involvement. This study evaluates the added value of intra-operative ultrasound (IOUS) in LAPC following FOLFIRINOX induction chemotherapy. METHODS: Prospective multicenter study in patients with LAPC who underwent explorative laparotomy with IOUS after FOLFIRINOX chemotherapy. Resectability was defined according to the National Comprehensive Cancer Network guidelines. IOUS findings were compared with preoperative CT-scans and pathology results. RESULTS: CT-staging in 38 patients with LAPC after FOLFIRINOX chemotherapy defined 22 patients LAPC, 15 borderline resectable and one resectable. IOUS defined 19 patients LAPC, 13 borderline resectable and six resectable. In 12/38 patients, IOUS changed the resectability status including five patients from borderline resectable to resectable and five patients from LAPC to borderline resectable. Two patients were upstaged from borderline resectable to LAPC. Tumor diameters were significantly smaller upon IOUS (31.7 ± 9.5 mm versus 37.1 ± 10.0 mm, p = 0.001) and resectability varied significantly (p = 0.043). Ultimately, 20 patients underwent resection of whom 14 were evaluated as (borderline) resectable on CT-scan, and 17 on IOUS. DISCUSSION: This prospective study demonstrates that IOUS may change the resectability status up to a third of patients with LAPC following FOLFIRINOX chemotherapy.

Comparison of MRI Activity Scoring Systems and Features for the Terminal Ileum in Patients With Crohn Disease.

OBJECTIVE: The purpose of this study was to evaluate four previously validated MRI activity scoring systems for diagnosis and grading of Crohn disease (CD) in the terminal ileum against an endoscopic and histopathologic reference standard. SUBJECTS AND METHODS: Ethics approval and written informed consent were obtained. Subjects with known or suspected CD were prospectively recruited between December 2011 and August 2014. Each patient underwent MRI and ileocolonoscopy with terminal ileum biopsies. Four MRI scoring systems (Magnetic Resonance Index of Activity [MaRIA], Clermont score, London score, and Crohn disease MRI Index) and component features were applied by two observers and correlated to the Crohn disease endoscopic index of severity (CDEIS, 0-44) and histopathologic endoscopic acute inflammation score (0-6). Interobserver agreement (weighted kappa and intraclass correlation coefficient [ICC]) and diagnostic accuracy for active and ulcerating endoscopic or histopathologic disease were evaluated. RESULTS: Ninety-eight patients (median age, 32 years old; 55 women, 43 men) were included. All four scoring systems showed good interobserver agreement (ICC = 0.70-0.78), moderate-to-strong correlation to CDEIS (r = 0.57-0.67) and weak-to-moderate correlation to endoscopic acute inflammation score (r = 0.38-0.49). Scoring systems' diagnostic accuracy for active and ulcerating endoscopic disease ranged from 73% to 78% and 71% to 76%, respectively, whereas for active histopathologic disease accuracy ranged from 65% to 72%. Between the scoring systems, no significant differences were found for both observers regarding interobserver agreement, correlation coefficients, and diagnostic accuracy. CONCLUSION: All scoring systems were comparable in terms of interobserver agreement, correlation to the endoscopic and histopathologic reference standard, and diagnostic accuracy. The London score, MaRIA, and Clermont score have the additional benefit of having validated cutoff values for both active and ulcerating endoscopic disease.

Comparison of contrast-enhanced and diffusion-weighted MRI in assessment of the terminal ileum in Crohn's disease patients.

PURPOSE: The purpose of the study was to compare the performance of contrast-enhanced (CE)-MRI and diffusion-weighted imaging (DW)-MRI in grading Crohn's disease activity of the terminal ileum. METHODS: Three readers evaluated CE-MRI, DW-MRI, and their combinations (CE/DW-MRI and DW/CE-MRI, depending on which protocol was used at the start of evaluation). Disease severity grading scores were correlated to the Crohn's Disease Endoscopic Index of Severity (CDEIS). Diagnostic accuracy, severity grading, and levels of confidence were compared between imaging protocols and interobserver agreement was calculated. RESULTS: Sixty-one patients were included (30 female, median age 36). Diagnostic accuracy for active disease for CE-MRI, DW-MRI, CE/DW-MRI, and DW/CE-MRI ranged between 0.82 and 0.85, 0.75 and 0.83, 0.79 and 0.84, and 0.74 and 0.82, respectively. Severity grading correlation to CDEIS ranged between 0.70 and 0.74, 0.66 and 0.70, 0.69 and 0.75, and 0.67 and 0.74, respectively. For each reader, CE-MRI values were consistently higher than DW-MRI, albeit not significantly. Confidence levels for all readers were significantly higher for CE-MRI compared to DW-MRI (P < 0.001). Further increased confidence was seen when using combined imaging protocols. CONCLUSIONS: There was no significant difference of CE-MRI and DW-MRI in determining disease activity, but the higher confidence levels may favor CE-MRI. DW-MRI is a good alternative in cases with relative contraindications for the use of intravenous contrast medium.

Preoperative Risk Score to Predict Occult Metastatic or Locally Advanced Disease in Patients with Resectable Perihilar Cholangiocarcinoma on Imaging.

BACKGROUND: Many patients with resectable perihilar cholangiocarcinoma (PHC) on imaging are diagnosed intraoperatively with occult metastatic or locally advanced disease, precluding a curative-intent resection. This study aimed to develop and validate a preoperative risk score. STUDY DESIGN: Patients with resectable PHC on imaging who underwent operations in 2 high-volume centers (US and Europe) between 2000 and 2015 were included. Multivariable logistic regression analysis was used to develop the risk score. Cross-validation was used to validate the score, alternating the 2 centers as "training" and "testing" datasets. RESULTS: Of 566 patients who underwent operations, 309 (55%) patients had a resection, and in 257 (45%) patients, a curative-intent resection was precluded due to distant metastasis (n = 151 [27%]) or locally advanced disease (n = 106 [19%]). Preoperative predictors included bilirubin >2 mg/dL, bile duct involvement on imaging, portal vein involvement on imaging (≥180 degrees), hepatic artery involvement on imaging (≥180 degrees), and suspicious lymph nodes on imaging. The new risk score (c-index 0.75 after cross-validation) provided significantly more accurate predictions than the Bismuth classification (c-index 0.62), Blumgart T-staging (c-index 0.67), and cTNM staging (c-index 0.68). The new risk score identified 4 risk groups for occult metastatic or locally advanced disease: low (14.7%), intermediate (29.5%), high (47.3%), and very high risk (81.3%). The preoperative score groups also predicted survival after operation, irrespective of intraoperative findings (p < 0.001). CONCLUSIONS: The validated risk score can predict occult distant metastatic or locally advanced PHC based on 5 preoperatively available factors. The score can be useful in preoperative shared decision making and selection of patients in neoadjuvant clinical trials.

Semiautomatic Assessment of the Terminal Ileum and Colon in Patients with Crohn Disease Using MRI (the VIGOR++ Project).

RATIONALE AND OBJECTIVES: The objective of this study was to develop and validate a predictive magnetic resonance imaging (MRI) activity score for ileocolonic Crohn disease activity based on both subjective and semiautomatic MRI features. MATERIALS AND METHODS: An MRI activity score (the "virtual gastrointestinal tract [VIGOR]" score) was developed from 27 validated magnetic resonance enterography datasets, including subjective radiologist observation of mural T2 signal and semiautomatic measurements of bowel wall thickness, excess volume, and dynamic contrast enhancement (initial slope of increase). A second subjective score was developed based on only radiologist observations. For validation, two observers applied both scores and three existing scores to a prospective dataset of 106 patients (59 women, median age 33) with known Crohn disease, using the endoscopic Crohn's Disease Endoscopic Index of Severity (CDEIS) as a reference standard. RESULTS: The VIGOR score (17.1 × initial slope of increase + 0.2 × excess volume + 2.3 × mural T2) and other activity scores all had comparable correlation to the CDEIS scores (observer 1: r = 0.58 and 0.59, and observer 2: r = 0.34-0.40 and 0.43-0.51, respectively). The VIGOR score, however, improved interobserver agreement compared to the other activity scores (intraclass correlation coefficient = 0.81 vs 0.44-0.59). A diagnostic accuracy of 80%-81% was seen for the VIGOR score, similar to the other scores. CONCLUSIONS: The VIGOR score achieves comparable accuracy to conventional MRI activity scores, but with significantly improved reproducibility, favoring its use for disease monitoring and therapy evaluation.

Adrenal Lesions in Patients With (Attenuated) Familial Adenomatous Polyposis and MUTYH-Associated Polyposis.

BACKGROUND: The reported proportion of patients with familial adenomatous polyposis who have adrenal lesions varies between 7% and 13% compared with 4% in the general population; the prevalence of adrenal lesions in patients with attenuated familial adenomatous polyposis and MUTYH-associated polyposis is unknown. Data on the clinical relevance and clinical course are limited. OBJECTIVE: We aimed to report on the frequency, characteristics, and progression of adrenal lesions in polyposis patients. DESIGN: This was a historical cohort study. SETTINGS: The study was performed at the Academic Medical Center, Amsterdam. PATIENTS: All of the patients with familial adenomatous polyposis, attenuated familial adenomatous polyposis, and MUTYH-associated polyposis were included. Medical charts and imaging reports were analyzed for data on adrenal lesions. A radiologist reassessed all of the images. Patients had not routinely been screened for adrenal lesions. MAIN OUTCOME MEASURES: The frequency, characteristics, and progression of adrenal lesions in patients with polyposis who underwent abdominal imaging were assessed. Findings were compared with a reference. RESULTS: A total of 39 adrenal lesions were identified in 23 (26%) of 90 patients with familial adenomatous polyposis, 2 (18%) of 11 with attenuated familial adenomatous polyposis, and 5 (24%) of 21 with MUTYH-associated polyposis. Mean age at time of detection was 50.7 years (range, 17.1-83.3 y). Median lesion size at baseline was 1.4 cm (range, 1.0-5.0 cm) versus 1.7 cm (range, 1.0-5.7 cm) after a median of 3.5 years (range, 1.0-11.4 y). Two patients were diagnosed with a hyperfunctioning lesion, and 4 underwent adrenalectomy: 3 lesions appeared benign, and 1 was oncocytic of uncertain malignant potential. The OR for detecting at least 1 lesion in a patient with polyposis versus reference was 6.2 (95% CI, 3.2-12.3), with no significant differences in ORs among the 3 syndromes. LIMITATIONS: The study was limited by its retrospective design. CONCLUSIONS: Adrenal lesions are frequent in patients with polyposis who undergo abdominal imaging. They appear to follow a benign and slowly progressive course and are mostly nonhyperfunctioning. See Abstract Video at http://links.lww.com/DCR/A323.

Prevalence and Progression of Pancreatic Cystic Precursor Lesions Differ Between Groups at High Risk of Developing Pancreatic Cancer.

OBJECTIVES: The aim of this study was to compare the prevalence of cystic pancreatic lesions and their natural behavior in 2 distinct high-risk groups for developing pancreatic ductal adenocarcinoma (PDAC): (1) carriers of a mutation that predisposes to PDAC and (2) individuals without a known gene mutation but with a family history of PDAC (familial pancreatic cancer [FPC]). METHODS: Pancreatic surveillance by annual magnetic resonance imaging and endoscopic ultrasound was performed in individuals with an estimated lifetime risk of developing PDAC of 10% or greater. Progression of a lesion was defined as growth 4 mm or greater or the development of worrisome features. RESULTS: We included 186 individuals: 98 mutation carriers and 88 FPC individuals (mean follow-up, 51 months). Individuals with FPC were significantly more likely than mutation carriers to have a pancreatic cyst 10 mm or greater (16% vs 5%, P = 0.045). Pancreatic cysts detected in mutation carriers, however, were significantly more likely to progress than those in FPC individuals (16% vs 2%, P = 0.050). CONCLUSIONS: This study provides evidence that the prevalence and growth characteristics of pancreatic cysts differ between distinct high-risk groups: individuals with FPC have a higher prevalence of pancreatic cysts 10 mm or greater, whereas cysts in mutation carriers are more likely to progress. These observations may help to develop more optimally tailored surveillance strategies in specific high-risk populations.

Long-Term Performance of Readers Trained in Grading Crohn Disease Activity Using MRI.

RATIONALE AND OBJECTIVES: We aim to evaluate the long-term performance of readers who had participated in previous magnetic resonance imaging (MRI) reader training in grading Crohn disease activity. MATERIALS AND METHODS: Fourteen readers (8 women; 12 radiologists, 2 residents; mean age 40; range 31-59), who had participated in a previous MRI reader training, participated in a follow-up evaluation after a mean interval of 29 months (range 25-34 months). Follow-up evaluation comprised 25 MRI cases of suspected or known Crohn disease patients with direct feedback; cases were identical to the evaluation set used in the initial reader training (of which readers were unaware). Grading accuracy, overstaging, and understaging were compared between training and follow-up using a consensus score by two experienced abdominal radiologists as the reference standard. RESULTS: In the follow-up evaluation, overall grading accuracy was 73% (95% confidence interval [CI]: 62%-81%), which was comparable to reader training grading accuracy (72%, 95% CI: 61%-80%) (P = .66). Overstaging decreased significantly from 19% (95% CI: 12%-27%) to 13% (95% CI: 8%-21%) between training and follow-up (P = .03), whereas understaging increased significantly from 9% (95% CI: 4%-21%) to 14% (95% CI: 7%-26%) (P < .01). CONCLUSIONS: Readers have consistent long-term accuracy for grading Crohn disease activity after case-based reader training with direct feedback.

Burden of waiting for surveillance CT colonography in patients with screen-detected 6-9 mm polyps.

PURPOSE: We assessed the burden of waiting for surveillance CT colonography (CTC) performed in patients having 6-9 mm colorectal polyps on primary screening CTC. Additionally, we compared the burden of primary and surveillance CTC. MATERIALS AND METHODS: In an invitational population-based CTC screening trial, 101 persons were diagnosed with <3 polyps 6-9 mm, for which surveillance CTC after 3 years was advised. Validated questionnaires regarding expected and perceived burden (5-point Likert scales) were completed before and after index and surveillance CTC, also including items on burden of waiting for surveillance CTC. McNemar's test was used for comparison after dichotomization. RESULTS: Seventy-eight (77 %) of 101 invitees underwent surveillance CTC, of which 66 (85 %) completed the expected and 62 (79 %) the perceived burden questionnaire. The majority of participants (73 %) reported the experience of waiting for surveillance CTC as 'never' or 'only sometimes' burdensome. There was almost no difference in expected and perceived burden between surveillance and index CTC. Waiting for the results after the procedure was significantly more burdensome for surveillance CTC than for index CTC (23 vs. 8 %; p = 0.012). CONCLUSION: Waiting for surveillance CTC after primary CTC screening caused little or no burden for surveillance participants. In general, the burden of surveillance and index CTC were comparable. KEY POINTS: • Waiting for surveillance CTC within a CRC screening caused little burden • The vast majority never or only sometimes thought about their polyp(s) • In general, the burden of index and surveillance CTC were comparable • Awaiting results was more burdensome for surveillance than for index CTC.

Computer tomography colonography participation and yield in patients under surveillance for 6-9 mm polyps in a population-based screening trial.

PURPOSE: Surveillance CT colonography (CTC) is a viable option for 6-9 mm polyps at CTC screening for colorectal cancer. We established participation and diagnostic yield of surveillance and determined overall yield of CTC screening. MATERIAL AND METHODS: In an invitational CTC screening trial 82 of 982 participants harboured 6-9 mm polyps as the largest lesion(s) for which surveillance CTC was advised. Only participants with one or more lesion(s) ≥6 mm at surveillance CTC were offered colonoscopy (OC); 13 had undergone preliminary OC. The surveillance CTC yield was defined as the number of participants with advanced neoplasia in the 82 surveillance participants, and was added to the primary screening yield. RESULTS: Sixty-five of 82 participants were eligible for surveillance CTC of which 56 (86.2 %) participated. Advanced neoplasia was diagnosed in 15/56 participants (26.8 %) and 9/13 (69.2 %) with preliminary OC. Total surveillance yield was 24/82 (29.3 %). No carcinomas were detected. Adding surveillance results to initial screening CTC yield significantly increased the advanced neoplasia yield per 100 CTC participants (6.1 to 8.6; p < 0.001) and per 100 invitees (2.1 to 2.9; p < 0.001). CONCLUSION: Surveillance CTC for 6-9 mm polyps has a substantial yield of advanced adenomas and significantly increased the CTC yield in population screening. KEY POINTS: • The participation rate in surveillance CT colonography (CTC) is 86 %. • Advanced adenoma prevalence in a 6-9 mm CTC surveillance population is high. • Surveillance CTC significantly increases the yield of population screening by CTC. • Surveillance CTC for 6-9 mm polyps is a safe strategy. • Surveillance CTC is unlikely to yield new important extracolonic findings.

Evolution of Screen-Detected Small (6-9 mm) Polyps After a 3-Year Surveillance Interval: Assessment of Growth With CT Colonography Compared With Histopathology.

OBJECTIVES: Volumetric growth assessment has been proposed for predicting advanced histology at surveillance computed tomography (CT) colonography (CTC). We examined whether is it possible to predict which small (6-9 mm) polyps are likely to become advanced adenomas at surveillance by assessing volumetric growth. METHODS: In an invitational population-based CTC screening trial, 93 participants were diagnosed with one or two 6-9 mm polyps as the largest lesion(s). They were offered a 3-year surveillance CTC. Participants in whom surveillance CTC showed lesion(s) of ≥6 mm were offered colonoscopy. Volumetric measurements were performed on index and surveillance CTC, and polyps were classified into growth categories according to ±30% volumetric change (>30% growth as progression, 30% growth to 30% decrease as stable, and >30% decrease as regression). Polyp growth was related to histopathology. RESULTS: Between July 2012 and May 2014, 70 patients underwent surveillance CTC after a mean surveillance interval of 3.3 years (s.d. 0.3; range 3.0-4.6 years). In all, 33 (35%) of 95 polyps progressed, 36 (38%) remained stable, and 26 (27%) regressed, including an apparent resolution in 13 (14%) polyps. In 68 (83%) of the 82 polyps at surveillance, histopathology was obtained; 15 (47%) of 32 progressing polyps were advanced adenomas, 6 (21%) of 28 stable polyps, and none of the regressing polyps. CONCLUSIONS: The majority of 6-9 mm polyps will not progress to advanced neoplasia within 3 years. Those that do progress to advanced status can in particular be found among the lesions that increased in size on surveillance CTC.

Preoperative biliary drainage in perihilar cholangiocarcinoma: identifying patients who require percutaneous drainage after failed endoscopic drainage.

BACKGROUND AND STUDY AIMS: Preoperative biliary drainage is often initiated with endoscopic retrograde cholangiopancreatography (ERCP) in patients with potentially resectable perihilar cholangiocarcinoma (PHC), but additional percutaneous transhepatic catheter (PTC) drainage is frequently required. This study aimed to develop and validate a prediction model to identify patients with a high risk of inadequate ERCP drainage. PATIENTS AND METHODS: Patients with potentially resectable PHC and (attempted) preoperative ERCP drainage were included from two specialty center cohorts between 2001 and 2013. Indications for additional PTC drainage were failure to place an endoscopic stent, failure to relieve jaundice, cholangitis, or insufficient drainage of the future liver remnant. A prediction model was derived from the European cohort and externally validated in the USA cohort. RESULTS: Of the 288 patients, 108 (38%) required additional preoperative PTC drainage after inadequate ERCP drainage. Independent risk factors for additional PTC drainage were proximal biliary obstruction on preoperative imaging (Bismuth 3 or 4) and predrainage total bilirubin level. The prediction model identified three subgroups: patients with low risk (7%), moderate risk (40%), and high risk (62%). The high-risk group consisted of patients with a total bilirubin level above 150 µmol/L and Bismuth 3a or 4 tumors, who typically require preoperative drainage of the angulated left bile ducts. The prediction model had good discrimination (area under the curve 0.74) and adequate calibration in the external validation cohort. CONCLUSIONS: Selected patients with potentially resectable PHC have a high risk (62%) of inadequate preoperative ERCP drainage requiring additional PTC drainage. These patients might do better with initial PTC drainage instead of ERCP.

Diagnostic value of a pancreatic mass on computed tomography in patients undergoing pancreatoduodenectomy for presumed pancreatic cancer.

INTRODUCTION: Previous studies have shown that 5-14% of patients undergoing pancreatoduodenectomy for suspected malignancy ultimately are diagnosed with benign disease. A "pancreatic mass" on computed tomography (CT) is considered to be the strongest predictor of malignancy, but studies describing its diagnostic value are lacking. The aim of this study was to determine the diagnostic value of a pancreatic mass on CT in patients with presumed pancreatic cancer, as well as the interobserver agreement among radiologists and the additional value of reassessment by expert-radiologists. METHODS: Reassessment of preoperative CT scans was performed within a previously described multicenter retrospective cohort study in 344 patients undergoing pancreatoduodenectomy for suspected malignancy (2003-2010). Preoperative CT scans were reassessed by 2 experienced abdominal radiologists separately and subsequently in a consensus meeting, after defining a pancreatic mass as "a measurable space occupying soft tissue density, except for an enlarged papilla or focal steatosis". RESULTS: CT scans of 86 patients with benign and 258 patients with (pre)malignant disease were reassessed. In 66% of patients a pancreatic mass was reported in the original CT report, versus 48% and 50% on reassessment by the 2 expert radiologists separately and 44% in consensus (P < .001 vs original report). Interobserver agreement between the original CT report and expert consensus was fair (kappa = 0.32, 95% confidence interval 0.23-0.42). Among both expert-radiologists agreement was moderate (kappa = 0.47, 95% confidence interval 0.38-0.56), with disagreement on the presence of a pancreatic mass in 29% of cases. The specificity for malignancy of pancreatic masses identified in expert consensus was twice as high compared with the original CT report (87% vs 42%, respectively). Positive predictive value increased to 98% after expert consensus, but negative predictive value was low (12%). CONCLUSION: Clinicians need to be aware of potential considerable disagreement among radiologists about the presence of a pancreatic mass. The specificity for malignancy doubled by expert radiologist reassessment when a uniform definition of "pancreatic mass" was used.