Pancreatic Cancer and Its Mimics.

Pancreatic ductal adenocarcinoma (PDAC) is the most common primary pancreatic malignancy, ranking fourth in cancer-related mortality in the United States. Typically, PDAC appears on images as a hypovascular mass with upstream pancreatic duct dilatation and abrupt duct cutoff, distal pancreatic atrophy, and vascular encasement, with metastatic involvement including lymphadenopathy. However, atypical manifestations that may limit detection of the underlying PDAC may also occur. Atypical PDAC features include findings related to associated conditions such as acute or chronic pancreatitis, a mass that is isointense to the parenchyma, multiplicity, diffuse tumor infiltration, associated calcifications, and cystic components. Several neoplastic and inflammatory conditions can mimic PDAC, such as paraduodenal "groove" pancreatitis, autoimmune pancreatitis, focal acute and chronic pancreatitis, neuroendocrine tumors, solid pseudopapillary neoplasms, metastases, and lymphoma. Differentiation of these conditions from PDAC can be challenging due to overlapping CT and MRI features; however, certain findings can help in differentiation. Diffusion-weighted MRI can be helpful but also can be nonspecific. Accurate diagnosis is pivotal for guiding therapeutic planning and potential outcomes in PDAC and avoiding biopsy or surgical treatment of some of these mimics. Biopsy may still be required for diagnosis in some cases. The authors describe the typical and atypical imaging findings of PDAC and features that may help to differentiate PDAC from its mimics. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center. See the invited commentary by Zins in this issue.

Pancreatobiliary Maljunction-associated Gallbladder Cancer Is as Common in the West, Shows Distinct Clinicopathologic Characteristics and Offers an Invaluable Model for Anatomy-induced Reflux-associated Physio-chemical Carcinogenesis.

OBJECTIVE: To determine the associations of pancreatobiliary maljunction (PBM) in the West. BACKGROUND: PBM (anomalous union of common bile duct and pancreatic duct) is mostly regarded as an Asian-only disorder, with 200X risk of gallbladder cancer (GBc), attributed to reflux of pancreatic enzymes. Methods: Radiologic images of 840 patients in the US who underwent pancreatobiliary resections were reviewed for PBM and contrasted with 171 GBC cases from Japan. RESULTS: Eight % of the US GBCs (24/300) had PBM (similar to Japan; 15/ 171, 8.8%), in addition to 1/42 bile duct carcinomas and 5/33 choledochal cysts. None of the 30 PBM cases from the US had been diagnosed as PBM in the original work-up. PBM was not found in other pancreatobiliary disorders. Clinicopathologic features of the 39 PBM-associated GBCs (US:24, Japan:15) were similar; however, comparison with non-PBM GBCs revealed that they occurred predominantly in females (F/M = 3); at younger (<50-year-old) age (21% vs 6.5% in non-PBM GBCs; P = 0.01); were uncommonly associated with gallstones (14% vs 58%; P < 0.001); had higher rate of tumor-infiltrating lymphocytes (69% vs 44%; P = 0.04); arose more often through adenoma-carcinoma sequence (31% vs 12%; P = 0.02); and had a higher proportion of nonconventional carcinomas (21% vs 7%; P = 0.03). Conclusions: PBM accounts for 8% of GBCs also in the West but is typically undiagnosed. PBM-GBCs tend to manifest in younger age and often through adenoma-carcinoma sequence, leading to unusual carcinoma types. If PBM is encountered, cholecystectomy and surveillance of bile ducts is warranted. PBM-associated GBCs offer an invaluable model for variant anatomy-induced chemical (reflux-related) carcinogenesis.

Pancreatic ductal adenocarcinomas associated with intraductal papillary mucinous neoplasms (IPMNs) versus pseudo-IPMNs: relative frequency, clinicopathologic characteristics and differential diagnosis.

The literature is highly conflicted on what percentage of pancreatic ductal adenocarcinomas (PDACs) arise in association with intraductal papillary mucinous neoplasms (IPMNs). Some studies have claimed that even small (Sendai-negative) IPMNs frequently lead to PDAC. Recently, more refined pathologic definitions for mucin-lined cysts were provided in consensus manuscripts, but so far there is no systematic analysis regarding the frequency and clinicopathologic characteristics of IPMN-mimickers, i.e., pseudo-IPMNs. In this study, as the first step in establishing frequency, we performed a systematic review of the pathologic findings in 501 consecutive ordinary PDACs, which disclosed that 10% of PDACs had associated cysts ≥1 cm. While 31 (6.2%) of these were IPMN or mucinous cystic neoplasm (MCN), 19 (3.8%) were other cyst types that mimicked IPMN (pseudo-IPMNs) per recent WHO/consensus criteria. As the second step of the study, we performed a comparative clinicopathologic analysis by also including our entire surgical pathology/consultation databases that was comprised of 60 IPMN-associated PDACs, 30 MCN-associated PDACs and 40 pseudo-IPMN-associated PDACs. We found that 84% of true IPMNs were pre-operatively recognized, whereas IPMN was considered in differential diagnosis of 33% of pseudo-IPMNs. Of the 40 pseudo-IPMNs, there were 15 secondary duct ectasias; 6 large-duct-type PDACs; 5 pseudocysts; 5 cystic tumor necrosis; 4 simple mucinous cysts; 3 groove pancreatitis-associated paraduodenal wall cysts; and 2 congenital cysts. Microscopically, pseudo-IPMNs had at least partial mucinous-lining mimicking IPMN but had smaller cystic (mean = 1.9 cm) and larger PDAC (mean = 3.8 cm) components compared to true IPMNs (cyst = 5.7 cm; PDAC = 2.0 cm). In summary, in this pathologically verified analysis that utilized refined criteria, 10% of PDACs were discovered to have cysts ≥1 cm, about two-thirds of which were IPMN/MCN but about one-third were pseudo-IPMNs. True IPMNs underlying the PDACs are often large and are already diagnosed pre-operatively as having an IPMN component, whereas only a third of the pseudo-IPMNs receive IPMN diagnosis by imaging and their cysts are smaller. At the histopathologic level, pseudo-IPMNs are highly prone to misdiagnosis as IPMN, which presumably accounts for much higher association of IPMNs with PDAC as reported in some studies. The subtle but salient characteristics of pseudo-IPMNs elucidated in this study should be combined with careful radiological/clinical correlation in order to exclude pseudo-IPMNs.

Pancreatic Cystic Lesions and Malignancy: Assessment, Guidelines, and the Field Defect.

The widespread use of high-spatial-resolution cross-sectional imaging has led to an increase in detection of incidental pancreatic cystic lesions. These lesions are a diverse group, ranging from indolent and premalignant lesions to invasive cancers. The diagnosis of several of these lesions can be suggested on the basis of their imaging appearance, while many other lesions require follow-up imaging and/or aspiration. The smaller cystic lesions, often branch-duct intraductal papillary mucinous neoplasms, have overlapping imaging characteristics that make diagnostic assessment of the natural history and malignancy risk confusing. Expert panels have developed societal guidelines, based on a consensus, for surveillance of these lesions. However, these guidelines are often inconsistent and are constantly evolving as additional scientific data are accumulated. Identification of features associated with increased risk of malignancy is important for proper management. The concept of field defect, whereby pancreatic adenocarcinoma develops at a site different from the site of the pancreatic cyst, adds to the complexity of screening guidelines. As a result of the differences in guidelines, key stakeholders (eg, radiologists, gastroenterologists, and surgeons) must review and come to a consensus regarding which guideline, or combination of guidelines, to follow at their individual institutions. Standardized reporting and macros are helpful for ensuring the uniformity of interpretations. Radiologists play a critical role in the detection and characterization of pancreatic cystic lesions, in the follow-up recommendations for these lesions, and in the detection of associated cancer. An invited commentary by Zaheer is available online. Online supplemental material is available for this article. ©RSNA, 2021.

Gallbladder Carcinoma and Its Differential Diagnosis at MRI: What Radiologists Should Know.

Gallbladder carcinoma is the most common cancer of the biliary system. It is challenging to diagnose because patients are often asymptomatic or present with nonspecific symptoms that mimic common benign diseases. Surgical excision is the only curative therapy and is best accomplished at early non-locally advanced stages. Unfortunately, gallbladder cancer often manifests at late locally advanced stages, precluding cure. Early tumors are often incidentally detected at imaging or at cholecystectomy performed for another indication. Typical imaging features of localized disease include asymmetric gallbladder wall thickening, polyps larger than 1.0 cm, and a solid mass replacing the gallbladder lumen. Advanced tumors are often infiltrative and can be confusing at CT and MRI owing to their large size. Determination of the origin of the lesion is paramount to narrow the differential diagnosis but is often challenging. It is important to identify gallbladder cancer and distinguish it from other benign and malignant hepatobiliary processes. Since surgical resection is the only curative treatment option, radiologist understanding and interpretation of pathways of nodal and infiltrative tumor spread can direct surgery or preclude patients who may not benefit from surgery. While both CT and MRI are effective, MRI provides superior soft-tissue characterization of the gallbladder and biliary tree and is a useful imaging tool for diagnosis, staging, and evaluation of treatment response. ©RSNA, 2020.

A 73-gene proliferative transcriptomic signature predicts uterine serous carcinoma patient survival and response to primary therapy.

OBJECTIVES: To develop a transcriptomic signature capable of predicting overall survival (OS) for uterine serous carcinoma (USC). METHODS: RNAseq data for 58 USC patients were obtained from TCGA. Expression of 73 candidate genes was measured for 67 Augusta University (AU) samples using NanoString technology. RESULTS: Analysis of the TCGA RNAseq data identified 73 genes that individually predict prognosis for USC patients and an elastic net model with all 73 genes (USC73) distinguishes a good OS group with low USC73 score from a poor OS group with high USC73 score (5-year OS = 83.3% and 13.3% respectively, HR = 40.1; p = 3 × 10-8). This finding was validated in the independent AU cohort (HR = 4.3; p = 0.0004). The poor prognosis group with high USC73 score consists of 37.9% and 32.8% of patients in the TCGA and AU cohort respectively. USC73 score and pathologic stage independently contribute to OS and together provide the best prognostic value. Early stage, low USC73 patients have the best prognosis (5-year OS = 85.1% in the combined dataset), while advanced stage, high USC73 patients have the worst prognosis (5-year OS = 6.4%, HR = 30.5, p = 1.2 × 10-12). Consistent with the observed poor survival, primary cell cultures from high USC73 patients had higher proliferation rate and cell cycle progression; and high USC73 patients had lower rates of complete response to standard therapy. CONCLUSIONS: The USC73 transcriptomic signature and stage independently predict OS of USC patients and the best prediction is achieved using USC73 and stage. USC73 may also serve as a therapeutic biomarker to guide patient care.

Variant anatomy of the biliary system as a cause of pancreatic and peri-ampullary cancers.

BACKGROUND: The cause of most pancreatic and periampullary cancers (PAC) is unknown. Recently, anatomic variations such as pancreatobiliary maljunction have been recognized as risk factors, similar to Barrett-related gastro-esophageal cancers. METHODS: Pre-operative MRI from 860 pancreatic/biliary resections, including 322 PACs, were evaluated for low-union (cystic duct joining the common hepatic duct inside of the pancreas or within 5 mm of the pancreatic border) RESULTS: Low-union, seen <10% of the population, was present in 44% of PACs (73% distal bile duct/cholangiocarcinoma, 42% pancreatic head, and 34% ampullary). It was significantly lower(11%) in conditions without connection to the ductal system (thus not exposed to the ductal/biliary tract contents), namely mucinous cystic neoplasms and intrahepatic cholangiocarcinomas(p < 0.0001). Intra-pancreatic type low-union was seen in 16% of PACs versus 2% of controls(p < 0.0001). DISCUSSION: This study establishes an association between low-union and PACs, and points to an anatomy-induced chemical/bilious carcinogenesis. This may explain why most pancreas cancers are in the head. It is possible that the same chemical milieu, caused by conditions other than low-union/insertion, may also play a role in the remaining half of PACs. This opens various treatment opportunities including milieu modifications (chemoprevention), focused screening of at-risk patients, and early detection with possible corrective actions.

Multidetector CT Findings in the Abdomen and Pelvis after Damage Control Surgery for Acute Traumatic Injuries.

After experiencing blunt or penetrating trauma, patients in unstable condition who are more likely to die of uncorrected shock than of incomplete injury repairs undergo emergency limited exploratory laparotomy, which is also known as damage control surgery (DCS). This surgery is part of a series of resuscitation steps, with the goal of stabilizing the patient's condition, with rapid surgical control of hemorrhage followed by supportive measures in the intensive care unit before definitive repair of injuries. These patients often are imaged with multidetector CT within 24-48 hours of the initial surgery. Knowledge of this treatment plan is critical to CT interpretation, because there are anatomic derangements and foreign bodies that would not be present in patients undergoing surgery for other reasons. Patients may have injuries beyond the surgical field that are only identified at imaging, which can alter the care plan. Abnormalities related to the resuscitation period such as the CT hypoperfusion complex and ongoing hemorrhage can be recognized at CT. Familiarity with these imaging and clinical findings is important, because they can be seen not only in trauma patients after DCS but also in other patients in the critical care setting. The interpretation of imaging studies can be helped by an understanding of the diagnostic challenges of grading organ injuries with surgical materials in place and the awareness of potential artifacts on images in these patients. Online supplemental material is available for this article. ©RSNA, 2019 See discussion on this article by LeBedis .

Uncommon Intraluminal Tumors of the Gallbladder and Biliary Tract: Spectrum of Imaging Appearances.

Intraluminal pathologic conditions of the bile ducts and gallbladder are common, most frequently consisting of calculi and adenocarcinoma. In recent years, intraductal papillary neoplasm of the bile ducts (IPN-B), which is analogous to intraductal papillary mucinous neoplasm of the pancreas, has been recognized as a distinct pathologic entity and a precursor lesion to adenocarcinoma of the bile ducts. Intraductal tubulopapillary neoplasm (ITPN) of the bile duct was subsequently described as a distinct pathologic entity. With increased awareness and advances in imaging techniques, these lesions are diagnosed with increased frequency at preoperative imaging. A similar neoplasm in the gallbladder is referred to as intracholecystic papillary neoplasm. These lesions are often diagnosed at a preinvasive stage and have a better prognosis than invasive cholangiocarcinoma when treated with curative resection, underscoring the importance of an accurate imaging diagnosis. The most common causes of polypoid lesions of the gallbladder are cholesterol polyps and adenomyomatosis. These lesions need to be differentiated from the less common but clinically important adenocarcinoma of the gallbladder. Imaging is crucial to identify polyps that are at high risk for malignancy so that the appropriate management choice between imaging follow-up and cholecystectomy can be made by the treating physicians. Other less common gallbladder tumors, such as gallbladder adenomas, lymphoma, and metastases to the gallbladder, can manifest as intraluminal tumors; and awareness of these lesions is also important. In this article, the recent literature is reviewed; and the imaging appearances, histopathologic findings, and management of uncommon intraluminal tumors of the bile ducts and gallbladder and their mimics are discussed. ©RSNA, 2019.

Secondary Hypertension and Complications: Diagnosis and Role of Imaging.

Hypertension is a common problem; if left untreated, it can result in significant complications, including those involving the cardiovascular system and end organs. Approximately 10% of patients with hypertension are classified as having secondary hypertension, defined as hypertension attributable to a specific and potentially remediable cause. The evaluation for secondary hypertension typically begins with acquiring the patient history and performing a physical examination and screening laboratory tests. Directed imaging may be performed, on the basis of laboratory test results, to assess for potential causes of secondary hypertension. The causes can be broadly classified as endocrine (eg, hyperaldosteronism, pheochromocytoma, hyperparathyroidism) and nonendocrine (eg, aortic coarctation, renal vascular hypertension). In addition, patients with hypertension can develop significant complications that also are diagnosed with imaging, including conditions involving the cardiovascular system (eg, aortic aneurysm, acute aortic syndrome) and central nervous system (eg, stroke, subarachnoid hemorrhage, and posterior reversible encephalopathy syndrome). The imaging workup and imaging appearances of some of the causes of secondary hypertension are reviewed, treatment options are discussed, and the imaging appearances of hypertension-related complications are described. It is important for radiologists to accurately diagnose the secondary causes of hypertension, as many of them are treatable, and treatment may result in improved symptoms or resolution of hypertension. ©RSNA, 2019.

Notice of Withdrawal: No Incidence of Nephrogenic Systemic Fibrosis after Gadobenate Dimeglumine Administration in Patients Undergoing Dialysis or Those with Severe Chronic Kidney Disease.

The authors have requested to withdraw this manuscript from publication because the study was not conducted in full accordance with the relevant institutional IRB protocol. © RSNA, 2018.

Radiologic and Histopathologic Correlation of Different Growth Patterns of Metastatic Uveal Melanoma to the Liver.

PURPOSE: The purpose of this study was to correlate magnetic resonance imaging (MRI) radiographic results with histopathologic growth patterns of metastatic uveal melanoma (UM) to the liver. DESIGN: Clinicopathologic correlation. PARTICIPANTS: Patients with metastatic UM to the liver. METHODS: A retrospective review of MRI images of patients with metastatic UM to the liver at a single institution between 2004 and 2016 was performed. The MRI growth patterns were classified as nodular or diffuse. The histopathologic findings of core liver biopsies of liver metastases identified by needle localization in a subset of these patients were reviewed. The core samples were evaluated by routine light microscopy, including immunohistochemical/immunofluorescent staining for CD31, CD105, and HMB45, and classified as exhibiting an infiltrative or nodular growth pattern. MAIN OUTCOME MEASURES: Magnetic resonance images and core biopsy findings. RESULTS: A total of 32 patients were identified with metastatic UM to the liver that was imaged by MRI, and 127 lesions were identified. A total of 46 lesions were classified by MRI as infiltrative and 81 as nodular. There were 9 needle-localized core biopsies that corresponded to MRI of metastatic lesions. Of these 9 lesions, 3 that were classified as infiltrative on MRI exhibited stage I infiltrative histologic growth patterns; of the remaining 6 that were classified as nodular by MRI, 5 histologically demonstrated stage II or stage III infiltrative growth patterns and 1 histologically demonstrated a nodular growth pattern. CONCLUSIONS: Magnetic resonance imaging of hepatic infiltrative growth patterns of metastatic UM corresponded to stage I histologic infiltrative growth in the sinusoidal spaces, whereas MRI nodular growth patterns corresponded to stage II/III histologic infiltrative growth that replaced the hepatic lobule or histologic nodular growth in the portal triad that effaced adjacent hepatic parenchyma.

Spectrum of Extratesticular and Testicular Pathologic Conditions at Scrotal MR Imaging.

Diagnostic workup of scrotal lesions should begin with a complete clinical history and physical examination, including analysis of risk factors such as family history of testicular cancer, personal history of tumor in the contralateral testis, and cryptorchidism, followed by imaging. Scrotal ultrasonography (US) with a combination of gray-scale and color Doppler techniques has been the first-line imaging modality for evaluation of testicular and extratesticular lesions because of its low cost, wide availability, and high diagnostic accuracy. However, US has limitations related to operator dependence, the relatively small field of view, and lack of tissue characterization. Magnetic resonance (MR) imaging, because of its superior soft-tissue contrast and multiplanar capabilities, is increasingly being used as a supplemental diagnostic problem-solving tool in cases where scrotal US findings are inconclusive or nondiagnostic. In addition to morphology, lesion location, and tissue characterization (eg, fat, blood products, granulation tissue, and fibrosis), scrotal MR imaging provides important information that can affect surgical planning and improve patient care. MR imaging also is helpful for differentiating testicular and extratesticular lesions, distinguishing between benign and malignant lesions, and evaluating the local extent of disease. This review discusses the anatomy and MR imaging features of testicular and extratesticular neoplastic and nonneoplastic conditions and describes relevant MR imaging techniques. ©RSNA, 2018 Contact information that appeared in the print version of this article was updated in the online version on May 14, 2018.

Reminiscing on Remnants: Imaging of Meckel Diverticulum and Its Complications in Adults.

OBJECTIVE: Meckel diverticulum may become symptomatic if it is complicated by hemorrhage, intestinal obstruction, diverticulitis, or tumor. Although classically described in children, it is often missed in adults because of lack of suspicion and difficulty in detection. The purpose of this article is to review the imaging findings and management of Meckel diverticulum and its complications. CONCLUSION: Although it is infrequently encountered incidentally, Meckel diverticulum should be considered especially when interpreting examinations for abdominal pain, small-bowel obstruction, and gastrointestinal bleeding.

Pulmonary Function Tests for the Radiologist.

Pulmonary function tests (PFTs) provide important quantitative information about lung function and can be used to elucidate pathologic conditions responsible for respiratory symptoms, assess the severity and course of disease, and evaluate the patient for suitability and timing for lung transplantation. They are typically used in tandem with chest imaging, along with other ancillary data, to arrive at a specific diagnosis. PFTs may provide the radiologist with clues to the diagnosis and grading of a wide variety of pulmonary diseases. In this review, the authors discuss the clinical use of PFTs, their major components, and important measurements and graphical representations that are essential for understanding and interpreting the results. The key components of PFT panels-static lung volumes, dynamic lung function (spirometry), and diffusion capacity-are explained. The authors present a general algorithmic approach for problem solving, with recognition of common patterns of results (obstructive, restrictive, mixed, nonspecific, and normal). Pulmonary diseases from each of the major patterns and chest imaging are illustrated, and correlations between particular PFT results and disease severity and morphology at imaging are examined. Common pitfalls encountered during interpretation are also highlighted. A basic understanding of the mechanics of PFTs, characteristic patterns in important diseases, and correlation between lung function and imaging findings may assist the radiologist in diagnosis and follow-up of key pulmonary diseases and strengthen the radiologist's role as part of a multidisciplinary diagnostic team. Online supplemental material is available for this article. ©RSNA, 2017.

Role of Imaging in the Evaluation of Male Infertility.

Infertility is defined herein as the inability to achieve pregnancy after frequently engaging in unprotected sexual intercourse for 1 year. Among infertile couples, the cause of infertility involves the male partner in approximately 50% of cases. Male infertility is usually caused by conditions affecting sperm production, sperm function, or both, or blockages that prevent the delivery of sperm. Chronic health problems, injuries, lifestyle choices, anatomic problems, hormonal imbalances, and genetic defects can have a role in male infertility. The diagnostic workup of male infertility should include a thorough medical and reproductive history, physical examination, and semen analysis, followed by imaging. The main role of imaging is identification of the causes of infertility, such as congenital anomalies and disorders that obstruct sperm transport and may be correctable. Scrotal ultrasonography is the most common initially performed noninvasive examination used to image the male reproductive system, including the testes and extratesticular structures such as the epididymis. Magnetic resonance (MR) imaging is another noninvasive imaging modality used in the pelvis to evaluate possible obstructive lesions involving the ductal system. MR imaging of the brain is extremely useful for evaluating relevant neurologic abnormalities, such as pituitary gland disorders, that are suspected on the basis of hormone analysis results. Invasive techniques are usually reserved for therapeutic interventions in patients with known abnormalities. In this article, the causes and imaging findings of obstructive and nonobstructive azoospermia are discussed. In addition to detecting treatable conditions that are related to male infertility, identifying the life-threatening entities associated with infertility and the genetic conditions that could be transmitted to offspring-especially in patients who undergo assisted reproduction-is critical. ©RSNA, 2017.

Safety and Quality of 1.5-T MRI in Patients With Conventional and MRI-Conditional Cardiac Implantable Electronic Devices After Implementation of a Standardized Protocol.

OBJECTIVE: The purpose of this study was to evaluate the safety and diagnostic utility of 1.5-T MRI examinations of individuals with conventional and MRI-conditional cardiac implantable electronic devices (CIEDs). SUBJECTS AND METHODS: Patients with a CIED who were referred for MRI were evaluated by radiologists and cardiac electrophysiologists for study participation. CIED interrogation was performed immediately before and after MRI, and cardiac telemetry monitoring was performed during MRI. CIED programming changes, malfunctions, and intraprocedural events were documented. Whether diagnostic questions were answered and whether artifacts related to the CIED were present and negatively affected image interpretation were recorded. RESULTS: One hundred thirteen MRI examinations were performed for 104 patients with CIEDs (74 pacemakers [60 conventional, 14 MRI conditional]; 39 implantable cardiac defibrillators). Device reprogramming was required before MRI for 62.8% of studies (71/113). No significant changes in lead parameters were noted during or after MRI. Electromagnetic noise was detected on at least one lead in 7.1% of studies. Three patients reported transient symptoms (one case each of heating at the pocket site, tingling at the pocket site, and palpitations). All images were considered diagnostic for the original clinical query. Artifacts related to CIEDs were described in 3.5% of MRI reports (4/113) and were present only when the pulse generator was included in the FOV. CIED-related artifacts limited evaluation of tissues immediately adjacent to the pulse generator. CONCLUSION: Establishment of a multidisciplinary work flow allows individuals with conventional and MRI-conditional CIEDs to safely undergo 1.5-T MRI with diagnostic questions consistently answered.

Hematospermia Evaluation at MR Imaging.

Hematospermia is a challenging and anxiety-provoking condition that can manifest as a single episode or recur over the course of weeks to months. It is usually a benign self-limiting condition in younger sexually active males without a history of risk factors such as cancer, urogenital malformations, bleeding disorders, and their associated symptoms. However, patients with recurrent, refractory and painful hematospermia with associated symptoms, such as fever, pain, or weight loss, require evaluation through clinical assessment and noninvasive investigations to rule out underlying pathologic conditions such as ejaculatory obstruction, infectious and inflammatory causes, malignancy, vascular malformations, and systemic disorders that increase the risk of bleeding, especially when presenting in older men. If these investigations are negative, the patient should be reassured and treated accordingly. In the recent past, magnetic resonance (MR) imaging has assumed a major role in the investigation of hematospermia due to its excellent soft-tissue contrast and multiplanar capabilities. In this review, we will discuss the potential causes of hematospermia and its diagnostic workup, including pathophysiology, anatomic considerations, the imaging appearance of associated pathologic conditions, and management. (©)RSNA, 2016.

Immediate post-doxorubicin drug-eluting beads chemoembolization Mr Apparent diffusion coefficient quantification predicts response in unresectable hepatocellular carcinoma: A pilot study.

PURPOSE: To investigate magnetic resonance imaging (MRI) diffusion-weighted imaging (DWI) of hepatocellular carcinoma (HCC) immediately post-doxorubicin drug-eluting beads transcatheter arterial chemoembolization (DEB-TACE) therapy as an early imaging biomarker of therapy response. MATERIALS AND METHODS: In a single-center prospective correlative study, 12 consecutive patients, median age 64 years, underwent DEB-TACE and dynamic contrast-enhanced (DCE) and DWI (b = 50,400,800 s/mm(2)) MRI at baseline with respect to first DEB-TACE, within 3 hours, and at 1 and 3 months posttherapy. DCE imaging response was evaluated according to target mRECIST and EASL. Relative change (RC) in apparent diffusion coefficient (ADC) of treated lesions was measured on follow-ups. Correlation between ADC RC in tumors and anatomical response were evaluated with paired t-test and receiver operator characteristic (ROC) curve. Survival from first DEB-TACE was estimated using Kaplan-Meier and log-rank analysis. RESULTS: Compared to baseline, mean ADC increased significantly for responders within 3 hours post-DEB-TACE (0.73 ± 0.20 mm(2) /s vs. 0.99 ± 0.28 mm(2) /s × 10(-3) (P = 0.001)). There was no significant change in ADC within 3 hours for nonresponders. ADC RC threshold of 20% immediately post-DEB-TACE showed 100% sensitivity and specificity in predicting anatomical response at 1 and 3 months with patients with ≥20% ADC increase demonstrated significantly prolonged mean overall survival compared to others (25.4 vs. 13.3 months (P = 0.017)). CONCLUSION: ADC relative change of ≥20% immediately post-DEB-TACE is an accurate predictor of objective and quantitative treatment response and prolonged survival in unresectable HCC.

Baseline and Early MR Apparent Diffusion Coefficient Quantification as a Predictor of Response of Unresectable Hepatocellular Carcinoma to Doxorubicin Drug-Eluting Bead Chemoembolization.

PURPOSE: To investigate baseline and early apparent diffusion coefficients (ADC) derived from diffusion-weighted imaging (DWI) as a predictor of objective response (OR) and survival in unresectable hepatocellular carcinoma (HCC) treated with doxorubicin drug-eluting bead (DEB) transcatheter arterial chemoembolization. MATERIALS AND METHODS: In a prospective study, 57 patients underwent DEB chemoembolization. Dynamic contrast-enhanced magnetic resonance imaging and DWI were performed at baseline and 1 and 3 months after DEB chemoembolization. OR was evaluated per modified Response Evaluation Criteria In Solid Tumors (mRECIST) and European Association for the Study of the Liver (EASL) guidelines. Baseline ADCs of tumors that showed OR at 1 and 3 months were compared with nonresponding tumor ADCs by two-sample t test and receiver operating characteristic curves. Additionally, ADC changes at 30 days were correlated with OR. Finally, Kaplan­Meier analysis was used to compare survival between patients with lesions demonstrating more restricted baseline diffusion and others. RESULTS: At 1 month, 33 patients (60%) showed OR (21 complete responses and 12 partial responses). At baseline, tumors with OR at 1 month showed significantly more restricted diffusion (0.731 × 10(−3) mm2/s) compared with others (1.057 × 10(−3) mm2/s; P = .031). No difference between response rates at 1 and 3 months according to mRECIST and EASL was observed. For an area under the curve of 0.965, the sensitivity and specificity of predicting objective tumor response at 1 month using a baseline HCC ADC of 0.83 × 10(−3) mm2/s were 91% and 96%, respectively. In addition, patients with lesions with a baseline ADC < 0.83 × 10(−3) mm2/s showed prolonged survival compared with others (P < .001). CONCLUSIONS: In unresectable HCC, a baseline ADC < 0.83 × 10(−3) mm2/s is a predictor of survival and treatment response at 1 and 3 months after DEB chemoembolization with high sensitivity and specificity.