Pancreatic Cysts: Radiology.

This article reviews the types of pancreatic cysts encountered in Radiologic practice. It summarizes the malignancy risk of each of the following: serous cystadenoma, mucinous cystic tumor, intraductal papillary mucinous neoplasm main duct and side branch, and some miscellaneous cysts such as neuroendocrine tumor and solid pseudopapillary epithelial neoplasm. Specific reporting recommendations are given. The choice between radiology follow-up versus endoscopic analysis is discussed.

Pancreatic Cystic Lesions: Next Generation of Radiologic Assessment.

Pancreatic cystic lesions are frequently identified on cross-sectional imaging. As many of these are presumed branch-duct intraductal papillary mucinous neoplasms, these lesions generate much anxiety for the patients and clinicians, often necessitating long-term follow-up imaging and even unnecessary surgical resections. However, the incidence of pancreatic cancer is overall low for patients with incidental pancreatic cystic lesions. Radiomics and deep learning are advanced tools of imaging analysis that have attracted much attention in addressing this unmet need, however, current publications on this topic show limited success and large-scale research is needed.

Structured versus non-structured reporting of pelvic MRI for ileal pouch evaluation: clarity and effectiveness.

PURPOSE: Given that ileal pouch-anal anastomosis (IPAA) surgery is a technically challenging and high-morbidity procedure, there are numerous pertinent imaging findings that need to be clearly and efficiently communicated to the IBD surgeons for essential patient management and surgical planning. Structured reporting has been increasingly used over the past decade throughout various radiology subspecialties to improve reporting clarity and completeness. We compare structured versus non-structured reporting of pelvic MRI for ileal pouch to evaluate for clarity and effectiveness. METHODS: 164 consecutive pelvic MRI's for ileal pouch evaluation, excluding subsequent exams for the same patient, acquired between 1/1/2019 and 7/31/2021 at one institution were included, before and after implementation (11/15/2020) of a structured reporting template, which was created with institutional IBD surgeons. Reports were assessed for the presence of 18 key features required for complete ileal pouch assessment: anastomosis (IPAA, tip of J, pouch body), cuff (length, cuffitis), pouch body (size, pouchitis, stricture), pouch inlet/pre-pouch ileum (stricture, inflammation, sharp angulation), pouch outlet (stricture), peripouch mesentery (position, mesentery twist), pelvic abscess, peri-anal fistula, pelvic lymph nodes, and skeletal abnormalities. Subgroup analysis was performed based on reader experience and divided into three categories: experienced (n = 2), other intra-institutional (n = 20), or affiliate site (n = 6). RESULTS: 57 (35%) structured and 107 (65%) non-structured pelvic MRI reports were reviewed. Structured reports contained 16.6 [SD:4.0] key features whereas non-structured reports contained 6.3 [SD:2.5] key features (p < .001). The largest improvement following template implementation was for reporting sharp angulation of the pouch inlet (91.2% vs. 0.9%, p < .001), tip of J suture line and pouch body anastomosis (both improved to 91.2% from 3.7%). Structured versus non-structured reports contained mean 17.7 versus 9.1 key features for experienced readers, 17.0 versus 5.9 for other intra-institutional readers, and 8.7 versus 5.3 for affiliate site readers. CONCLUSION: Structured reporting of pelvic MRI guides a systematic search pattern and comprehensive evaluation of ileal pouches, and therefore facilitates surgical planning and clinical management. This standardized reporting template can serve as baseline at other institutions for adaptation based on specific radiology and surgery preferences, fostering a collaborative environment between radiology and surgery, and ultimately improving patient care.

Standardization of MRI Screening and Reporting in Individuals With Elevated Risk of Pancreatic Ductal Adenocarcinoma: Consensus Statement of the PRECEDE Consortium.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a dismal survival rate. Screening the general population for early detection of PDAC is not recommended, but because early detection improves survival, high-risk individuals, defined as those meeting criteria based on a family history of PDAC and/or the presence of known pathogenic germline variant genes with PDAC risk, are recommended to undergo screening with MRI and/or endoscopic ultrasound at regular intervals. The Pancreatic Cancer Early Detection (PRECEDE) Consortium was formed in 2018 and is composed of gastroenterologists, geneticists, pancreatic surgeons, radiologists, statisticians, and researchers from 40 sites in North America, Europe, and Asia. The overarching goal of the PRECEDE Consortium is to facilitate earlier diagnosis of PDAC for high-risk individuals to increase survival of the disease. A standardized MRI protocol and reporting template are needed to enhance the quality of screening examinations, improve consistency of clinical management, and facilitate multiinstitutional research. We present a consensus statement to standardize MRI screening and reporting for individuals with elevated risk of pancreatic cancer.

Reporting Templates for MRI and Water-Soluble Contrast Enema in Patients With Ileal Pouch-Anal Anastomosis: Experience From a Large Referral Center.

Ileal pouch-anal anastomosis (IPAA) surgery is the reference standard surgical procedure for treatment of ulcerative colitis and most patients with familial adenomatous polyposis. This procedure allows preservation of fecal continence and gastrointestinal continuity. However, it is associated with a wide variety of complications, which often have nonspecific and overlapping clinical presentations, making imaging an important part of workup for pouch dysfunction. The purpose of this article is to propose structured reporting templates for MRI and water-soluble contrast enema (WSCE), based on our referral pouch center's experience, in patients who have undergone IPAA surgery. We review salient surgical technique, pouch anatomy, and imaging protocols, with an emphasis on a systematic search pattern for evaluation of ileal pouch complications using proposed structured reporting templates for MRI and WSCE.

Testing for Verification Bias in Reported Malignancy Risks for Side-Branch Intraductal Papillary Mucinous Neoplasms: A Simulation Modeling Approach.

OBJECTIVE: The objective of our study was to test for the possibility that published malignancy risks for side-branch intraductal papillary mucinous neoplasms (IPMNs) are overestimates, likely due to verification bias. MATERIALS AND METHODS: We tested for possible verification bias using simulation modeling techniques. First, in age-defined hypothetical cohorts of 10 million persons, we projected the frequency of pancreatic ductal adenocarcinoma (PDAC) arising from side-branch IPMNs over 5 years using published estimates of their prevalence (4.4%) and rate of malignant transformation (1.9%). Second, we projected the total number of PDAC cases in corresponding cohorts over the same time horizon using national cancer registry data. For each cohort, we determined whether the percentage of all PDAC cases that arose from side-branch IPMNs (i.e., side-branch IPMN-associated PDAC cases) was clinically plausible using an upper limit of 10% to define plausibility, as estimated from the literature. Model assumptions and parameter uncertainty were evaluated in sensitivity analysis. RESULTS: Across all cohorts, percentages of side-branch IPMN-associated PDACs greatly exceeded 10%. In the base case (mean age = 55.7 years), 80% of PDAC cases arose from side-branch IPMNs (7877/9786). In the oldest cohort evaluated (mean age = 75 years), this estimate was 76% (14,227/18,714). In a secondary analysis, we found that if an upper limit threshold of 10% for side-branch IPMN-associated PDAC was imposed, the model-predicted rate of malignancy for side-branch IPMNs would be less than 0.24% over a 5-year time horizon, substantially lower than most literature-based estimates. CONCLUSION: Our results suggest that reported malignancy risks associated with side-branch IPMNs are likely to be overestimates and imply the presence of verification bias.

Imaging Follow-up of Low-Risk Incidental Pancreas and Kidney Findings: Effects of Patient Age and Comorbidity on Projected Life Expectancy.

Purpose To determine the effects of patient age and comorbidity level on life expectancy (LE) benefits associated with imaging follow-up of Bosniak IIF renal cysts and pancreatic side-branch (SB) intraductal papillary mucinous neoplasms (IPMNs). Materials and Methods A decision-analytic Markov model to evaluate LE benefits was developed. Hypothetical cohorts with varied age (60-80 years) and comorbidities (none, mild, moderate, or severe) were evaluated. For each finding, LE projections from two strategies were compared: imaging follow-up and no imaging follow-up. Under follow-up, it was assumed that cancers associated with the incidental finding were successfully treated before they spread. For patients without follow-up, mortality risks from Bosniak IIF cysts (renal cell carcinoma) and SBIPMNs (pancreatic ductal adenocarcinoma) were incorporated. Model assumptions and parameter uncertainty were evaluated in sensitivity analysis. Results In the youngest, healthiest cohorts (age, 60 years; no comorbidities), projected LE benefits from follow-up were as follows: Bosniak IIF cyst, 6.5 months (women) and 5.8 months (men); SBIPMN, 6.4 months (women) and 5.3 months (men). Follow-up of Bosniak IIF cysts in 60-year-old women with severe comorbidities yielded a LE benefit of 3.9 months; in 80-year-old women with no comorbidities, the benefit was 2.8 months, and with severe comorbidities the benefit was 1.5 months. Similar trends were observed in men and for SBIPMN. Results were sensitive to the performance of follow-up for cancer detection; malignancy risks; and stage at presentation of malignant, unfollowed Bosniak IIF cysts. Conclusion With progression of age and comorbidity level, follow-up of low-risk incidental findings yields increasingly limited benefits for patients. © RSNA, 2018 Online supplemental material is available for this article.

A Randomized Study of Patient Risk Perception for Incidental Renal Findings on Diagnostic Imaging Tests.

OBJECTIVE: The purpose of this study is to assess differences in patient distress, risk perception, and treatment preferences for incidental renal findings with descriptive versus combined descriptive and numeric graphical risk information. MATERIALS AND METHODS: A randomized survey study was conducted for adult patients about to undergo outpatient imaging studies at a large urban academic institution. Two survey arms contained either descriptive or a combination of descriptive and numeric graphical risk information about three hypothetical incidental renal findings at CT: 2-cm (low risk) and 5-cm (high risk) renal tumors and a 2-cm (low risk) renal artery aneurysm. The main outcomes were patient distress, perceived risk (qualitative and quantitative), treatment preference, and valuation of lesion discovery. RESULTS: Of 374 patients, 299 participated (79.9% response rate). With inclusion of numeric and graphical, rather than only descriptive, risk information about disease progression for a 2-cm renal tumor, patients reported less worry (3.56 vs 4.12 on a 5-point scale; p < 0.001) and favored surgical consultation less often (29.3% vs 46.9%; p = 0.003). The proportion choosing surgical consultation for the 2-cm renal tumor decreased to a similar level as for the renal artery aneurysm with numeric risk information (29.3% [95% CI, 21.7-36.8%] and 27.9% [95% CI, 20.5-35.3%], respectively). Patients overestimated the absolute risk of adverse events regardless of risk information type, but significantly more so when given descriptive information only, and valued the discovery of lesions regardless of risk information type (range, 4.41-4.81 on a 5-point scale). CONCLUSION: Numeric graphical risk communication for patients about incidental renal lesions may facilitate accurate risk comprehension and support patients in informed decision making.

Management of Incidental Pancreatic Cysts: A White Paper of the ACR Incidental Findings Committee.

The ACR Incidental Findings Committee (IFC) presents recommendations for managing pancreatic cysts that are incidentally detected on CT or MRI. These recommendations represent an update from the pancreatic component of the JACR 2010 white paper on managing incidental findings in the adrenal glands, kidneys, liver, and pancreas. The Pancreas Subcommittee-which included abdominal radiologists, a gastroenterologist, and a pancreatic surgeon-developed this algorithm. The recommendations draw from published evidence and expert opinion, and were finalized by informal iterative consensus. Algorithm branches successively categorize pancreatic cysts based on patient characteristics and imaging features. They terminate with an ascertainment of benignity and/or indolence (sufficient to discontinue follow-up), or a management recommendation. The algorithm addresses most, but not all, pathologies and clinical scenarios. Our goal is to improve quality of care by providing guidance on how to manage incidentally detected pancreatic cysts.

Rethinking Normal: Benefits and Risks of Not Reporting Harmless Incidental Findings.

The authors explore the benefits and risks of not reporting imaging findings that do not have clinical relevance, with the goal of developing recommendations to reduce their reporting. The authors review the example of incidentally detected, simple renal cysts (Bosniak category I), including medicolegal conditions required for such a shift in reporting practices to be acceptable. The authors propose four potential criteria for not reporting clinically unimportant findings and recommend that these criteria be debated in other contexts, so that they can be refined and implemented.

CT enterography at 100 kVp with iterative reconstruction compared to 120 kVp filtered back projection: evaluation of image quality and radiation dose in the same patients.

PURPOSE: To perform qualitative and quantitative comparison of images in same patients undergoing CT enterography (CTE) with 100 kVp iterative reconstruction and 120 kVp filtered back projection. METHODS: In this retrospective study, 50 consecutive patients who underwent imaging with 100 kVp and iterative reconstruction (100-IR) and had prior imaging with 120 kVp filtered back projection (120-FBP) were included. Subjective image quality parameters were evaluated by two independent and blinded readers, with higher score implying better image quality. We developed a quantitative measure of image sharpness by measuring edge-width of the psoas-fat interface. Image noise was measured as a standard deviation of attenuation measurement in the homogeneous region of the subcutaneous fat. Image sharpness and noise were measured and compared between 100-IR and 120-FBP acquisitions. RESULTS: There was approximately 33% lower radiation dose as estimated by CTDIvol with 100-IR compared to 120-FBP (9.95 vs. 15.0; p < 0.0001). There were no significant differences in overall image quality, bowel wall sharpness, and subjective assessment of noise and artifact between 100-IR and 120-FBP for both readers. Mesenteric vessel clarity score was significantly higher with 100-IR for 1 reader (4.34 vs. 4.04; p = 0.008), but not for the second reader. There was higher image sharpness (1.62 vs. 1.89; p < 0.0001) and higher image noise (14.4 vs. 13.2; p = 0.020) with 100-IR compared to 120-FBP acquisition. CONCLUSIONS: CTE performed at 100 kVp with iterative reconstruction demonstrates dose reduction without significant impact on various measures of image quality when compared to conventional 120 kVp FBP.

Pancreatic ductal adenocarcinoma radiology reporting template: consensus statement of the Society of Abdominal Radiology and the American Pancreatic Association.

Pancreatic ductal adenocarcinoma is an aggressive malignancy with a high mortality rate. Proper determination of the extent of disease on imaging studies at the time of staging is one of the most important steps in optimal patient management. Given the variability in expertise and definition of disease extent among different practitioners as well as frequent lack of complete reporting of pertinent imaging findings at radiologic examinations, adoption of a standardized template for radiology reporting, using universally accepted and agreed on terminology for solid pancreatic neoplasms, is needed. A consensus statement describing a standardized reporting template authored by a multi-institutional group of experts in pancreatic ductal adenocarcinoma that included radiologists, gastroenterologists, and hepatopancreatobiliary surgeons was developed under the joint sponsorship of the Society of Abdominal Radiologists and the American Pancreatic Association. Adoption of this standardized imaging reporting template should improve the decision-making process for the management of patients with pancreatic ductal adenocarcinoma by providing a complete, pertinent, and accurate reporting of disease staging to optimize treatment recommendations that can be offered to the patient. Standardization can also help to facilitate research and clinical trial design by using appropriate and consistent staging by means of resectability status, thus allowing for comparison of results among different institutions.

Pancreatic ductal adenocarcinoma radiology reporting template: consensus statement of the society of abdominal radiology and the american pancreatic association.

Pancreatic ductal adenocarcinoma is an aggressive malignancy with a high mortality rate. Proper determination of the extent of disease on imaging studies at the time of staging is one of the most important steps in optimal patient management. Given the variability in expertise and definition of disease extent among different practitioners as well as frequent lack of complete reporting of pertinent imaging findings at radiologic examinations, adoption of a standardized template for radiology reporting, using universally accepted and agreed on terminology for solid pancreatic neoplasms, is needed. A consensus statement describing a standardized reporting template authored by a multi-institutional group of experts in pancreatic ductal adenocarcinoma that included radiologists, gastroenterologists, and hepatopancreatobiliary surgeons was developed under the joint sponsorship of the Society of Abdominal Radiologists and the American Pancreatic Association. Adoption of this standardized imaging reporting template should improve the decision-making process for the management of patients with pancreatic ductal adenocarcinoma by providing a complete, pertinent, and accurate reporting of disease staging to optimize treatment recommendations that can be offered to the patient. Standardization can also help to facilitate research and clinical trial design by using appropriate and consistent staging by means of resectability status, thus allowing for comparison of results among different institutions.

Journal club: How radiation exposure histories influence physician imaging decisions: a multicenter radiologist survey study.

OBJECTIVE: The purpose of this article is to evaluate the influence of patient radiation exposure histories on radiologists' imaging decisions. MATERIALS AND METHODS: We conducted a physician survey study in three academic medical centers. Radiologists were asked to make an imaging recommendation for a hypothetical patient with a history of multiple CT scans. We queried radiologists' decision making, evaluating whether they incorporated cancer risks from previous imaging, reported acceptance (or rejection) of the linear no-threshold model, and understood linear no-threshold model implications in this setting. Consistency between radiologists' decisions and their linear no-threshold model beliefs was evaluated; those acting in accordance with the linear no-threshold model were expected to disregard previously incurred cancer risks. A Fisher exact test was used to verify the generalizability of results across institutions and training levels (residents, fellows, and attending physicians). RESULTS: Fifty-six percent (322/578) of radiologists completed the survey. Most (92% [295/322]) incorporated risks from the patient's exposure history during decision making. Most (61% [196/322]) also reported acceptance of the linear no-threshold model. Fewer (25% [79/322]) rejected the linear no-threshold model; 15% (47/322) could not judge. Among radiologists reporting linear no-threshold model acceptance or rejection, the minority (36% [98/275]) made decisions that were consistent with their linear no-threshold model beliefs. This finding was not statistically different across institutions (p = 0.070) or training levels (p = 0.183). Few radiologists (4% [13/322]) had an accurate understanding of linear no-threshold model implications. CONCLUSION: Most radiologists, when faced with patient exposure histories, make decisions that contradict their self-reported acceptance of the linear no-threshold model and the linear no-threshold model itself. These findings underscore a need for educational initiatives.

Unusual solid pancreatic tumors.

The vast array of possible histologies for a given pancreatic mass makes the specific diagnosis of a solid pancreatic mass in an individual patient challenging. This article discusses and reviews the imaging findings of those entities that are likely to be encountered in clinical practice, specifically pancreatic endocrine tumors, solid pseudopapillary tumor, secondary pancreatic masses, and heterotopic spleen.