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Purpose: This study aims to combine multiparametric magnetic resonance imaging (MRI) and digitized pathology with machine learning to generate predictive maps of histologic features for prostate cancer localization. Methods and Materials: Thirty-nine patients underwent MRI prior to prostatectomy. After surgery, tissue was sliced according to MRI orientation using patient-specific 3-dimensionally printed slicing jigs. Whole-mount sections were annotated by our pathologist and digitally contoured to differentiate the lumen and epithelium. Slides were co-registered to the T2-weighted MRI scan. A learning curve was generated to determine the number of patients required for a stable machine-learning model. Patients were randomly stratified into 2 training sets and 1 test set. Two partial least-squares regression models were trained, each capable of predicting lumen and epithelium density. Predicted density values were calculated for each patient in the test dataset, mapped into the MRI space, and compared between regions confirmed as high-grade prostate cancer. Results: The learning-curve analysis showed that a stable fit was achieved with data from 10 patients. Maps indicated that regions of increased epithelium and decreased lumen density, generated from each independent model, corresponded with pathologist-annotated regions of high-grade cancer. Conclusions: We present a radio-pathomic approach to mapping prostate cancer. We find that the maps are useful for highlighting high-grade tumors. This technique may be relevant for dose-painting strategies in prostate radiation therapy. © 2018 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)., Summary This study aims to combine whole-mount prostate pathology with multiparametric magnetic resonance imaging from 39 patients to generate predictive maps of epithelium and lumen density in magnetic resonance imaging space. We show that the new image contrasts generated stratify high-grade tumors from low-grade tumors and healthy tissue. Future studies will explore targeted radiation therapy and clinical disease staging using the radio-pathomic mapping technique.

Selective screening for pancreatic cancer (PC) has been proposed. We describe the establishment of a comprehensive multidisciplinary screening program using 3.0 T MRI. Criteria for screening included the presence of PC in: ≥ 2 first degree relatives (FDR), 1 FDR and 1 s degree relative (SDR), ≥ 3 any degree relatives (ADR), or any known hereditary cancer syndrome with increased PC risk. Imaging with 3.0 T MRI was performed routinely and endoscopic ultrasound was used selectively. Screening was completed in 75 patients (pts). Hereditary cancer syndromes were present in 42 (56%) of the 75 pts: BRCA2 (18), ATM (8), BRCA1 (6), CDKN2A (4), PALB2 (3), Lynch (2), and Peutz-Jeghers (1). A family history of PC was present in ≥ 2 FDR in 12 (16%) pts, 1 FDR and 1 SDR in 5 (7) pts, and ≥ 3 ADR in 16 (21%) pts. Of the 65 pts who received screening MRI, 28 (43%) pts had pancreatic cystic lesions identified, including 1 (1%) patient in whom a cholangiocarcinoma was diagnosed as well. No patient underwent surgical resection. Using a 3.0 T MRI to screen patients at high risk for developing PC identified radiographic abnormalities in 43% of patients, which were stable on subsequent surveillance. Specific guidelines for the frequency of surveillance and indications for surgery remain areas of active investigation as the global experience with high risk screening continues to mature.

Prostate cancer is the most common noncutaneous cancer in men in the United States. The current paradigm for screening and diagnosis is imperfect, with relatively low specificity, high cost, and high morbidity. This study aims to generate new image contrasts by learning a distribution of unique image signatures associated with prostate cancer. In total, 48 patients were prospectively recruited for this institutional review board–approved study. Patients underwent multiparametric magnetic resonance imaging 2 weeks before surgery. Postsurgical tissues were annotated by a pathologist and aligned to the in vivo imaging. Radiomic profiles were generated by linearly combining 4 image contrasts (T2, apparent diffusion coefficient [ADC] 0-1000, ADC 50-2000, and dynamic contrast-enhanced) segmented using global thresholds. The distribution of radiomic profiles in high-grade cancer, low-grade cancer, and normal tissues was recorded, and the generated probability values were applied to a naive test set. The resulting Gleason probability maps were stable regardless of training cohort, functioned independent of prostate zone, and outperformed conventional clinical imaging (area under the curve [AUC] = 0.79). Extensive overlap was seen in the most common image signatures associated with high- and low-grade cancer, indicating that low- and high-grade tumors present similarly on conventional imaging.

Gallbladder adenomyomatosis (GA) is a benign gallbladder entity discovered as an asymptomatic gallbladder mass. Since gallbladder cancer is in the differential diagnosis for gallbladder masses, the ability to differentiate benign disease avoids a more extensive oncologic resection. This study sought to review imaging modalities used to diagnose GA.PubMed and SciVerse Scopus were systematically searched using the terms: "gallbladder adenomyomatosis" and "gallbladder imaging" for articles published between January 2000 and January 2015.A total of 14 articles were reviewed in this analysis. Contemporary series report the use of ultrasound (US), computed tomography (CT) or magnetic resonance imaging (MRI) in GA imaging. Ultrasound detection of Rokitansky-Aschoff sinuses, visualized as small cystic spaces with associated "comet-tail" or "twinkling" artifact, is pathognomonic for GA. A "Pearl-Necklace" sign of small connected sinuses on MRI or "Rosary" sign on CT are additional characteristics that may assist in establishing a diagnosis.Ultrasound is the most commonly used tool to investigate GA. If not diagnostic, CT or MRI are effective in attempting to differentiate a benign or malignant cholecystic mass. Characteristic signs should lead the surgeon to perform a laparoscopic cholecystectomy in symptomatic patients or manage non-operatively in asymptomatic patients.

Pancreas transplantation aims to restore physiologic normoglycemia in diabetic patients with glomerulopathy and avoid or delay the onset of diabetic retinopathy and arteriopathy. Simultaneous pancreas-kidney transplant is the most common approach, using a cadaveric pancreas donation in conjunction with either cadaveric or live donor renal transplant. Alternative techniques include pancreas after kidney transplant, in which the pancreas transplant is performed some years after renal transplant. Pancreas transplant alone is utilized rarely in diabetic patients with compensated renal function. Pancreas grafts have vascular and enteric connections that vary in their anatomic approach, and understanding of this is critical for imaging with ultrasonography, computed tomography, or magnetic resonance imaging. Imaging techniques are directed to display the pancreatic transplant arterial and venous vasculature, parenchyma, and intestinal drainage pathway. Critical vascular information includes venous thrombosis (partial or complete), arterial occlusion, or aneurysm. Parenchymal abnormalities are nonspecific and occur in pancreatitis, graft rejection, and subsequent graft ischemia. Peripancreatic fluid collections include hematoma/seroma, pseudocyst, and abscess. The latter two are related to pancreatitis, duct disruption, or leak from the duodenojejunostomy. An understanding of transplant anatomy and complications will lead to appropriate use of imaging techniques to diagnose or exclude important complications.

he discovery of pancreatic calcifications has long been used in the diagnosis of pancreatic disease, and for many years imaging of the pancreas was largely limited to the radiographic identification of these calcifications. Today, our ability to image the pancreas has greatly advanced with modalities including CT, sonography, endoscopic retrograde cholangiopancreatography, and MR imaging. This improved visualization of the pancreas allows better identification of pancreatic calcifications and their underlying cause. Traditionally, pancreatic calcifications have been largely associated with chronic calcific pancreatitis from alcohol abuse. Although alcohol abuse remains the predominant cause of pancreatic calcifications, many other causes also deserve attention. Knowing what entities cause calcifications and their typical appearance can help in an accurate diagnosis. However, imaging alone cannot be trusted for a definitive diagnosis because many of these entities overlap in their appearance [1]. We report a spectrum of causes and imaging appearances related to calcification of the pancreas.

Magnetic resonance (MR) angiography is a widely used, noninvasive tool for evaluating the aorta and its branches. It is particularly useful in renal transplant recipients because it provides anatomic detail of the transplant artery without nephrotoxic effects. Volume rendering is underutilized in MR angiography, but this technique affords high-quality three-dimensional MR angiograms, especially in cases of tortuous or complex vascular anatomy. An imaging protocol was developed that includes gadolinium-enhanced MR angiography of the transplant renal artery with volume rendering and multiplanar reformation postprocessing techniques. Axial T2-weighted and contrast material-enhanced T1-weighted MR images are also obtained to examine the renal parenchyma itself and to evaluate for hydronephrosis or peritransplant fluid collections. This imaging protocol allows rapid global assessment of the renal transplant arterial system, renal parenchyma, and peritransplant region. It can also help detect or exclude many of the various causes of renal transplant dysfunction (eg, stenosis or occlusion of a transplant vessel, peritransplant fluid collections, ureteral obstruction). Conventional angiography can thus be avoided in patients with normal findings and reserved for those with MR angiographic evidence of stenosis.

Most cases of abnormal placentation are associated with a history of one or more cesarean deliveries. Uterine leiomyomas and treatment for such a diagnosis are also risk factors for placenta accreta and should be viewed as such.A 34-year-old woman underwent a hysteroscopic myomectomy and became pregnant 6 months later. Ultrasonography and magnetic resonance imaging suggested a placenta percreta. Multidisciplinary care allowed for a safe delivery of her neonate and little maternal morbidity.Patients with a history of hysteroscopic myomectomy or other uterine leiomyoma treatment are at an increased risk for abnormal placentation. Imaging studies are suggested in such patients to coordinate multidisciplinary care to decrease maternal and fetal morbidity and mortality.

Recent data indicate that patients after the Fontan procedure are at risk for significant liver dysfunction; however, the prevalence and extent of liver disease in the Fontan population remains unknown. Furthermore, limited data exist in regard to screening for liver disease in adult Fontan patients. We sought to determine the prevalence of liver disease in adult patients following the Fontan procedure using computed tomography (CT) and serum biomarkers of liver fibrosis. Adult Fontan patients underwent screening for liver disease as part of their annual evaluation. Screening consisted of laboratory evaluation and dual-phase liver CT scan. Laboratory evaluation included analysis of liver function, viral hepatitis serologies, and FibroSURE panel (LabCorp), a test that analyzes the results of serum biomarkers to provide a quantitative surrogate marker for liver fibrosis. Sixteen patients, mean age 30.3 (range 20-41) years, were enrolled in the study. Mean length of follow-up from time of Fontan palliation was 20.5 (range 11-33) years. No patients had serologic evidence of viral hepatitis or synthetic liver dysfunction. Twelve patients (75%) had abnormal FibroSURE scores, seven (44%) had elevated FibroSURE scores predictive of Metavir fibrosis stage F2 or greater on liver biopsy, and one (6%) had a FibroSURE score predictive of cirrhosis on biopsy. All 16 patients had abnormal radiologic liver findings identified on CT, including heterogeneous enhancement in 11 (69%), varices in six (38%), and liver nodules in five patients (31%). Length of time since Fontan surgery correlated significantly with an elevated FibroSURE score (P = .05) and having more CT scan abnormalities (P = .04). Liver fibrosis detected by serum biomarkers and dual phase CT scan is common in adult patients following the Fontan procedure. Further studies are needed to determine the long-term clinical significance of these findings.

The aim of this study was to evaluate a new injection-acquisition technique performed using a multirow detector CT scanner for separation of three distinct hepatic circulatory phases (hepatic artery, portal venous inflow, hepatic venous) and to determine which of these phases is optimal for detecting hypervascular neoplasm.Two sequential acquisitions were performed during a single breath-hold followed by a third acquisition beginning 60 sec after injection. Injection-to-scan delay for the first acquisition was the individual patient's circulation time, which was determined by a preliminary mini bolus. The mean attenuation of the upper abdominal aorta, portal vein, and hepatic parenchyma were determined for each imaging pass in 20 patients with cirrhosis and 20 patients without cirrhosis. Tumor-to-liver contrast for hypervascular primary and metastatic neoplasm was evaluated in a different set of 16 cirrhotic patients and nine noncirrhotic patients. Three-dimensional CT arteriograms were obtained from first-pass data.Three distinct circulatory phases (hepatic artery, portal vein inflow or late arterial, and hepatic venous) were seen in cirrhotic and noncirrhotic patients. Maximum tumor-to-liver contrast for hypervascular primary and metastatic neoplasm occurred during the second pass for both cirrhotic (p0.006) and noncirrhotic (p0. 001) patients. A three-dimensional hepatic-mesenteric CT arteriogram of normal or anomalous hepatic vessels without venous overlay was obtained from first-pass data in all patients.Rapid-sequence hepatic helical CT allows selection of the optimal time interval for hypervascular tumor detection. A new paradigm for rapid hepatic CT acquisition-namely, hepatic arterial, portal vein inflow, and hepatic venous phases-is recommended to replace hepatic artery dominant and portal venous phases.