Delta Radiomic Features Predict Resection Margin Status and Overall Survival in Neoadjuvant-Treated Pancreatic Cancer Patients.

Background: Neoadjuvant therapy (NAT) emerged as the standard of care for patients with pancreatic ductal adenocarcinoma (PDAC) who undergo surgery; however, surgery is morbid, and tools to predict resection margin status (RMS) and prognosis in the preoperative setting are needed. Radiomic models, specifically delta radiomic features (DRFs), may provide insight into treatment dynamics to improve preoperative predictions.

Methods: We retrospectively collected clinical, pathological, and surgical data (patients with resectable, borderline, locally advanced, and metastatic disease), and pre/post-NAT contrast-enhanced computed tomography (CT) scans from PDAC patients at the University of Texas Southwestern Medical Center (UTSW; discovery) and Humanitas Hospital (validation cohort).

Intra- and inter-operator variability in MRI-based manual segmentation of HCC lesions and its impact on dosimetry.

Purpose: The aim was to quantify inter- and intra-observer variability in manually delineated hepatocellular carcinoma (HCC) lesion contours and the resulting impact on radioembolization (RE) dosimetry.

Methods: Ten patients with HCC lesions treated with Y-90 RE and imaged with post-therapy Y-90 PET/CT were selected for retrospective analysis. Three radiologists contoured 20 lesions manually on baseline multiphase contrast-enhanced MRIs, and two of the radiologists re-contoured at two additional sessions.

Differences in tumor-to-normal organ SUV ratios measured with 68 Ga-DOTATATE PET compared with 177 Lu-DOTATATE SPECT in patients with neuroendocrine tumors.

Background: Our goal is to quantitatively compare radiotracer biodistributions within tumors and major normal organs on pretherapy 68 Ga-DOTATATE PET to post-therapy 177 Lu-DOTATATE single-photon emission computed tomography (SPECT) in patients receiving peptide receptor radionuclide therapy (PRRT).

Methods: PET/CT at ~ 60 min postinjection of Ga-68 DOTATATE and research 177 Lu-SPECT/CT imaging ~ at 4 h (SPECT1) and ~ 24 h (SPECT2) post-cycle#1 were available. Manual contours of lesions on baseline CT or MRI were applied to co-registered SPECT/CT and PET/CT followed by deep learning-based CT auto-segmentation of organs.

Interrater Agreement of Bosniak Classification Version 2019 and Version 2005 for Cystic Renal Masses at CT and MRI.

Background The Bosniak classification system for cystic renal masses was updated in 2019 in part to improve agreement compared with the 2005 version. Purpose To compare and investigate interrater agreement of Bosniak version 2019 and Bosniak version 2005 at CT and MRI. Materials and Methods In this retrospective single-center study, a blinded eight-reader assessment was performed in which 195 renal masses prospectively considered Bosniak IIF-IV (95 at CT, 100 at MRI, from 2006 to 2019 with version 2005) were re-evaluated with Bosniak versions 2019 and 2005.

LI-RADS Treatment Response Algorithm: Performance and Diagnostic Accuracy With Radiologic-Pathologic Explant Correlation in Patients With SBRT-Treated Hepatocellular Carcinoma.

Purpose: Our purpose was to evaluate the accuracy of LI-RADS Treatment Response Algorithm (LR-TRA) for assessing the viability of hepatocellular carcinoma (HCC) treated with stereotactic body radiation therapy (SBRT), using explant pathology as the gold standard.

Methods And Materials: This retrospective study included patients who underwent SBRT for locoregional treatment of HCC between 2008 and 2019 with subsequent liver transplantation. Five radiologists independently assessed all treated lesions by using the LR-TRA.

Pretreatment Levels of Soluble Tumor Necrosis Factor Receptor 1 and Hepatocyte Growth Factor Predict Toxicity and Overall Survival After Y Radioembolization: Potential Novel Application of Biomarkers for Personalized Management of Hepatotoxicity.

Liver function may be negatively affected by radiation for treatment of hepatic malignancy. Pretreatment blood cytokine levels are biomarkers for prediction of toxicity and survival after external-beam radiation therapy. We hypothesized that cytokines may also predict outcomes after radioembolization, enabling a biomarker-driven personalized approach to treatment.

Society of Abdominal Radiology Disease Focused Panel Survey on Clinical Utilization of Incidental Pancreatic Cyst Management Recommendations and Template Reporting.

Objective: To assess current practice patterns with respect to protocols used for incidental pancreatic cyst follow-up, management guidelines, and template reporting.

Methods: The Society of Abdominal Radiology Disease Focused Panel on intraductal pancreatic neoplasms distributed an anonymous 14-question survey to its members in June 2018 that focused on current utilization of incidental pancreatic cyst guidelines, protocols, and template reporting.

Results: Among the 1,390 email invitations, 323 responded, and 94.

Tumor response prediction in Y radioembolization with PET-based radiomics features and absorbed dose metrics.

Purpose: To evaluate whether lesion radiomics features and absorbed dose metrics extracted from post-therapy Y PET can be integrated to better predict outcomes in microsphere radioembolization of liver malignancies METHODS: Given the noisy nature of Y PET, first, a liver phantom study with repeated acquisitions and varying reconstruction parameters was used to identify a subset of robust radiomics features for the patient analysis. In 36 radioembolization procedures, Y PET/CT was performed within a couple of hours to extract 46 radiomics features and estimate absorbed dose in 105 primary and metastatic liver lesions. Robust radiomics modeling was based on bootstrapped multivariate logistic regression with shrinkage regularization (LASSO) and Cox regression with LASSO.

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas: recommendations for Standardized Imaging and Reporting from the Society of Abdominal Radiology IPMN disease focused panel.

There have been many publications detailing imaging features of malignant transformation of intraductal papillary mucinous neoplasms (IPMN), management and recommendations for imaging follow-up of diagnosed or presumed IPMN. However, there is no consensus on several practical aspects of imaging IPMN that could serve as a clinical guide for radiologists and enable future data mining for research. These aspects include how to measure IPMN, define reporting terminology, standardize reporting and unify guidelines for surveillance.

Quantitative Imaging Assessment for Clinical Trials in Oncology.

Background: Objective radiographic assessment is crucial for accurately evaluating therapeutic efficacy and patient outcomes in oncology clinical trials. Imaging assessment workflow can be complex; can vary with institution; may burden medical oncologists, who are often inadequately trained in radiology and response criteria; and can lead to high interobserver variability and investigator bias. This article reviews the development of a tumor response assessment core (TRAC) at a comprehensive cancer center with the goal of providing standardized, objective, unbiased tumor imaging assessments, and highlights the web-based platform and overall workflow.

Prediction of Tumor Control in Y Radioembolization by Logit Models with PET/CT-Based Dose Metrics.

The aim of this work was to develop models for tumor control probability (TCP) in radioembolization with Y PET/CT-derived radiobiologic dose metrics. Patients with primary liver cancer or liver metastases who underwent radioembolization with glass microspheres were imaged with Y PET/CT for voxel-level dosimetry to determine lesion absorbed dose (AD) metrics, biological effective dose (BED) metrics, equivalent uniform dose, and equivalent uniform BED for 28 treatments (89 lesions). The lesion dose-shrinkage correlation was assessed on the basis of RECIST and, when available, modified RECIST (mRECIST) at first follow-up.

Impact of Y PET gradient-based tumor segmentation on voxel-level dosimetry in liver radioembolization.

Background: The purpose was to validate Y PET gradient-based tumor segmentation in phantoms and to evaluate the impact of the segmentation method on reported tumor absorbed dose (AD) and biological effective dose (BED) in Y microsphere radioembolization (RE) patients. A semi-automated gradient-based method was applied to phantoms and patient tumors on the Y PET with the initial bounding volume for gradient detection determined from a registered diagnostic CT or MR; this PET-based segmentation (PS) was compared with radiologist-defined morphologic segmentation (MS) on CT or MRI. AD and BED volume histogram metrics (D90, D70, mean) were calculated using both segmentations and concordance/correlations were investigated.

Hemostatic Agents and Tissue Sealants: Potential Mimics of Abdominal Abnormalities.

Objective: Topical tissue sealants and hemostatic agents, seen on postoperative imaging in a variety of intraabdominal and pelvic locations, have the potential to be mistaken for abdominal abnormalities, especially if the radiologist is not aware of the patient's surgical history. The normal appearance of these agents may mimic abscesses, tumors, enlarged lymph nodes, or retained foreign bodies. Therefore, it is important to be familiar with their typical imaging appearances and to review the surgical records when needed to avoid misdiagnoses.

Diagnostic accuracy of MDCT in differentiating gallbladder cancer from acute and xanthogranulomatous cholecystitis.

Objective: To determine the diagnostic accuracy of multi-detector CT (MDCT) for differentiating gallbladder cancer from acute and xanthogranulomatous cholecystitis using previously described imaging features.

Methods: In this IRB approved HIPAA-compliant retrospective cohort study, contrast-enhanced MDCT of histologically confirmed acute cholecystitis (n = 17), xanthogranulomatous cholecystitis (n = 25), and gallbladder cancer (n = 18) were reviewed independently by three abdominal radiologists blinded to outcome. The primary outcome was the diagnostic accuracy of MDCT for the differentiation of gallbladder cancer from cholecystitis (acute and xanthogranulomatous) using various imaging parameters.

Impact of Clinical History on Maximum PI-RADS Version 2 Score: A Six-Reader 120-Case Sham History Retrospective Evaluation.

Purpose To assess the impact of clinical history on the maximum Prostate Imaging Recording and Data System (PI-RADS) version 2 (v2) score assigned to multiparametric magnetic resonance (MR) imaging of the prostate. Materials and Methods This retrospective cohort study included 120 consecutively selected multiparametric prostate MR imaging studies performed between November 1, 2016, and December 31, 2016. Sham clinical data in four domains (digital rectal examination, prostate-specific antigen level, plan for biopsy, prior prostate cancer history) were randomly assigned to each case by using a balanced orthogonal design.

Promoter Methylation of BRCA1, DAPK1 and RASSF1A is Associated with Increased Mortality among Indian Women with Breast Cancer.

Background: Promoter methylation has been observed for several genes in association with cancer development and progression. Hypermethylation mediated-silencing of tumor suppressor genes (TSGs) may contribute to breast cancer pathogenesis. The present study was conducted to investigate the promoter methylation status of BRCA1, DAPK1 and RASSF1A genes in Indian women with breast cancer.

This challenging procedure has successful outcomes: Laparoscopic nephrectomy in inflammatory renal diseases.

In prospective study from November 2011- November 2013, we performed 44 laparoscopic nephrectomies for benign non-functioning kidney diseases. Twenty eight patients underwent laparoscopic transperitoneal nephrectomies (63.6%), ten were laparoscopic assisted (22.

Hypervascular pancreatic "lesions": a pattern-based approach to differentiation.

Hypervascular pancreatic lesions/masses can arise due to a variety of causes, both benign and malignant, leading to a wide differential diagnosis. Accurate differentiation of these lesions into appropriate diagnoses can be challenging; however, this is important for directing clinical management. This manuscript provides a multimodality imaging review of hypervascular pancreatic lesion, with emphasis on an imaging-based algorithmic approach for differentiation of these lesions, which may serve as a decision support tool when encountering these uncommon lesions.

Improved quantitative Y bremsstrahlung SPECT/CT reconstruction with Monte Carlo scatter modeling.

Purpose: In Y microsphere radioembolization (RE), accurate post-therapy imaging-based dosimetry is important for establishing absorbed dose versus outcome relationships for developing future treatment planning strategies. Additionally, accurately assessing microsphere distributions is important because of concerns for unexpected activity deposition outside the liver. Quantitative Y imaging by either SPECT or PET is challenging.

Gastroduodenal and pancreatic surgeries: indications, surgical techniques, and imaging features.

This review article focuses on gastroduodenal and pancreatic surgeries with the goal of identifying radiologic findings that translate to important surgical considerations. The topics covered include partial gastrectomy with reconstruction techniques, total gastrectomy, pancreaticoduodenectomy, and pancreaticojejunostomy. Indications, contraindications, surgical techniques, and postoperative imaging are described within each of these topics.

Update of Dual-Energy CT Applications in the Genitourinary Tract.

Objective: Dual-energy CT (DECT) is being increasingly used for abdominal imaging because it provides incremental benefit of material characterization without significant increase in radiation dose. This article provides an overview of current DECT techniques and use of DECT in urinary tract imaging for assessment of renal masses and urinary calculi characterization and in CT urography.

Conclusion: Incorporation of DECT into clinical practice and use of its material characterization capabilities in urinary tract imaging enable characterization of urinary calculi and incidental renal lesions and can reduce radiation dose by allowing generation of virtual unenhanced images.

White Paper of the Society of Computed Body Tomography and Magnetic Resonance on Dual-Energy CT, Part 3: Vascular, Cardiac, Pulmonary, and Musculoskeletal Applications.

This is the third of a series of 4 white papers that represent Expert Consensus Documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its Task Force on dual-energy computed tomography. This paper, part 3, describes computed tomography angiography and thoracic, cardiac, vascular, and musculoskeletal clinical applications. At the end of the discussion of each application category (vascular, cardiac, pulmonary, and musculoskeletal), we present our consensus opinions on the current clinical utility of the application and opportunities for further research.

White Paper of the Society of Computed Body Tomography and Magnetic Resonance on Dual-Energy CT, Part 1: Technology and Terminology.

This is the first of a series of 4 white papers that represent Expert Consensus Documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its task force on dual-energy computed tomography (DECT). This article, part 1, describes the fundamentals of the physical basis for DECT and the technology of DECT and proposes uniform nomenclature to account for differences in proprietary terms among manufacturers.

White Paper of the Society of Computed Body Tomography and Magnetic Resonance on Dual-Energy CT, Part 4: Abdominal and Pelvic Applications.

This is the fourth of a series of 4 white papers that represent expert consensus documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its task force on dual-energy computed tomography. This article, part 4, discusses DECT for abdominal and pelvic applications and, at the end of each, will offer our consensus opinions on the current clinical utility of the application and opportunities for further research.