68Ga-PSMA PET/CT in Recurrent Prostate Cancer after Radical Prostatectomy Using PSMA-RADS Version 2.0.

BACKGROUND: 68Ga-PSMA PET/CT is superior to standard-of-care imaging for detecting regional and distant metastatic recurrent prostate cancer. The objective of our study was to evaluate the performance of 68Ga-PSMAPET/CT in our patient population, using the new PSMA-RADS version 2.0. METHODS: A total of 128 patients scanned with 68Ga-PSMA PET/CT for detection of recurrence after RP were analyzed with PSMA-RADS version 2.0. For the analysis of the detection rate, categories PSMA-RADS 3 to 5 were considered as "positive for malignancy" and 1-2 as "negative". RESULTS: According to PSMA-RADS v2.0, we classified patients as follows: 23 patients without PSMA-RADS because they were negative; PSMA-RADS 1: 10 patients; PSMA-RADS 2: 4 patients; PSMA-RADS 3A: 11 patients; PSMA-RADS 3B: 2 patients; PSMA-RADS 3C: 2 patients; PSMA-RADS 3D: 2 patients; PSMA-RADS 4: 13 patients; PSMA-RADS 5: 61 patients. CONCLUSIONS: The overall detection rate of 68Ga-PSMA PET/CT was 71%. By dividing the patients into fourgroups according to PSA level before examination, we obtained the following detection rates: PSA < 0.2 ng/mL 38%; 0.2 ≤ PSA < 0.5 ng/mL 57%; 0.5 ≤ PSA ≤ 1 ng/mL 77%; and PSA > 1 ng/mL 95%. CONCLUSION: Using PSMA-RADS version 2.0, we obtained detection rate values comparable with recent literature both in absolute terms and in relation to different PSA levels.

Primary Leiomyosarcoma of the Mediastinum: A Rare and Challenging Diagnosis?

(1) Introduction: Leiomyosarcomas are highly aggressive mesenchymal neoplasm derived from smooth muscle cells which, in the mediastinum, are present in various primary organs; To our knowledge, less than 10 cases of primary mediastinal leiomyosarcoma have been described. Here, we report a compelling case of primary mediastinal leiomyosarcoma. (2) Case presentation: A 79-year-old woman was admitted to the Thoracic Surgery Unit of S. Andrea University Hospital for persisting cough, exertional dyspnea, and sternal pain. After multidisciplinary consultation, a CT-guided core needle biopsy of the mass was performed, resulting in a provisional diagnosis of mesenchymal neoplasm with smooth muscle differentiation without apparent signs of atypia. The patient underwent surgery that revealed a large irregularly shaped mass with a whorled pattern cut surface, showing admixed yellowish areas of necrosis and areas of hemorrhage. Histologic examination showed a smooth muscle neoplasm with atypia and necrosis, and a grade 2 primary mediastinal leiomyosarcoma diagnosis was given. (3) Conclusions: Soft tissue sarcomas represent a challenging diagnostic group of tumors due to their location, morphologic spectrum, and unique molecular background. Our case of primary mediastinal leiomyosarcoma shows how tumor heterogeneity and limited tissue sampling impact diagnosis. Further studies are needed to shed light on the disease by finding an appropriate molecular signature for each leiomyosarcoma subgroup, providing a more precise diagnosis and the correct background for tailored therapy.

Imaging of primary retroperitoneal neoplasms.

Retroperitoneal soft tissue tumors are frequently incidental findings on imaging tests as Computed tomography (CT) or Magnetic Resonance Imaging (MRI). Retroperitoneal soft tissue tumors are rare and therefore not common in daily radiological practice. Clinician and radiologist'skills to set retroperitoneal soft tissue tumors at presentation is crucial for a correct patient management. So far, several diagnostic algorithms have been proposed to assess retroperitoneal masses, which have not been validated by case histories (2-5). The aim of this article is to evaluate a new classification of retroperitoneal masses using CT and MRI. KEY WORDS: CT, Diagnosis, MRI, Retroperitoneum, Soft tissue sarcoma.

PET/CT in congenital hyperinsulinism: transforming patient's lives by molecular hybrid imaging.

Congenital hyperinsulinism (HI) is a life-threatening condition characterized by severe and recurrent episodes of hypoglycaemia due to defects in key genes involved in regulating insulin secretion. The delay in diagnosis and inappropriate management of HI lead to high risk of permanent hypoglycemic brain injury. The management of HI is challenging as each form of HI (focal, diffuse, and atypical) requires its own therapeutic strategy. In HI diagnostic work-up, integrated PET/CT scan is currently the first-line imaging technique allowing to differentiate between diffuse and focal form and, in the latter case, to localize the focus within the pancreas with high precision. Only in focal HI partial pancreatectomy is the treatment of choice and a curative surgical treatment means a real chance of transforming patient's lives and HI patient's future. The aim of this review is to discuss the role of PET/CT imaging in HI scenario, its technical advantages and limitations and how successful surgery is strongly dependent on accurate preoperative assessment (genetic analysis and PET/CT scan). A multidisciplinary approach in HI diagnosis and treatment inside a single team (involving different expertise) allows to manage children safely and properly, supporting their families in an organized care network.

Clinical application of 18F-DOPA PET/TC in pediatric patients.

The use 18F-DOPA PET/CT for oncologic and non-oncologic pediatric diseases is well consolidated in clinical practice. The indications include brain tumors, neuroendocrine malignancies and congenital hyperinsulinism. The number of papers involving pediatric subjects is steadily growing. However, literature still lacks clinical trials and large multicentric studies in contrast with the extensive literature available for adult patients. The aim of this review is to discuss the main clinical indications of 18F-DOPA in pediatric oncologic and nononcologic diseases and to analyze its role in diagnosis, staging, biopsy and surgical planning. The high resolution of PET/CT tomographs in addition to the high sensitivity and specificity of 18F-DOPA imaging exceeds the downsides linked to this nuclear medicine imaging modality. In fact, few potential limitations could discourage the use of PET/CT imaging. For example, similarly to MRI studies the long acquisition time of a PET/CT scan often requires sedation especially in infants. Moreover, the radiation exposure of a PET/CT scan may be high, but the clinical benefit deriving from nuclear medicine imaging outruns the risk connected to the use of ionizing radiations.

Seminal Vesicle Urinary Reflux After TURP Mimicking Vesicular Invasion From Prostate Cancer on 18F-Choline PET/CT.

Seminal vesicles are paired secretory glands located posterior to the bladder in men that produce seminal fluid to maintain sperm. Seminal vesicle reflux into the prostatic ducts may be associated with prostatitis in older patients or may represent a very rare complication of transurethral prostate resection in patients with prostatic cancer. This condition is frequently accidentally diagnosed on excretory urography and/or retrograde urethrogram. Clinical presentation includes pain, fever, recurrent epididymitis-prostatitis, and post void dribbling.

PET/CT in pediatric oncology.

The use of PET/CT in adult oncology has been consolidated by several and authoritative multicentric studies, metanalyses and systematic reviews. International guidelines help everyday nuclear medicine specialists, oncologists and radiologists in choosing the most suitable diagnostic path for each patient. Classifications based on traditional imaging and PET/CT findings define the most appropriate treatment and can predict the outcome for different types of malignancies. However, compared to adult patients the use of PET/CT in pediatric oncology is often burdened by lack of systematic and large multicentric studies and consequently accurate and precise guidelines. The cause of this shortage of large trials may be attributed to the rarity of these neoplasms and to the fear of long-term radiation effects on this peculiar category of patients. The aim of this article is to review the applications of PET/CT for imaging the most common pediatric neoplasms.

Magnetic Resonance of Small Bowel Tumors.

Tumors of the small intestine represent less than 5% of all gastrointestinal tract neoplasms. Magnetic resonance (MR) imaging is rapidly increasing clinical acceptance to evaluate the small bowel and can be the initial imaging method to investigate small bowel diseases. MR examinations may provide the first opportunity to detect and characterize tumors of the small bowel. Intraluminal and extraluminal MR findings, combined with contrast enhancement and functional information, allow accurate diagnoses and consequently characterization of small bowel neoplasms. This article describes the MR findings of primary small bowel neoplasms and the MR findings for the differential diagnosis are discussed.

MR Enterography in paediatric patients with obscure gastrointestinal bleeding.

OBJECTIVES: To evaluate the performance of Magnetic Resonance enterography (MRE) in the diagnostic work-up of children presenting with obscure gastrointestinal bleeding (OGIB). MATERIALS AND METHODS: From January 2014 to January 2016, a single-centre prospective study was performed on all children between 0 and 16 years of age referred to the radiology department for OGIB. Each child underwent MRE examination after negative oesophagogastroduodenoscopy and ileocolonoscopy. MRE results were recorded. All patients proceeded to the related gold standard for diagnostic confirmation. RESULTS: 25 patients (mean age 10.8±4.5 years, range 4 months to 16 years) were included. MRE was diagnostic in 76% (19 of 25). The most frequent diagnoses were intestinal polyp (28%) and Meckel's diverticulum (16%). Sensitivity and specificity of MRE were 86% and 100% respectively. There were no reported complications during any of the examinations. CONCLUSION: MRE is a safe and accurate imaging modality in the evaluation of paediatric OGIB. Its diagnostic capability is comparable to current evidence for capsule endoscopy in this patient group. Further research with larger sample sizes and standardized control groups is warranted to improve our understanding of MRE in this application.

Cancer anorexia: hypothalamic activity and its association with inflammation and appetite-regulating peptides in lung cancer.

BACKGROUND: Energy homeostasis is mediated by the hypothalamus, whose inflammation-induced functional derangements contribute to the onset of anorexia in cancer. By using functional magnetic resonance imaging (fMRI), we determined the patterns of hypothalamic activation after oral intake in anorexic (A), non-anorexic (NA) cancer patients, and in controls (C). METHODS: Lung cancer patients were considered. Hypothalamic activation was recorded in A and NA patients and in C by fMRI, before (T0), immediately after (T1) the administration of an oral nutritional supplement, and after 15 min (T2). The grey of the hypothalamus and Blood Oxygen Level Dependent (BOLD) intensity were calculated and normalized for basal conditions. Interleukin (IL)-1, IL-6, tumour necrosis factor (TNF)-α, ghrelin, and leptin plasma levels were measured. A statistical parametric mapping was used. RESULTS: Thirteen lung cancer patients (7 M, 6 F; 9A, 4NA) and 2 C (1 M, 1 F) were enrolled. Controls had the lowest BOLD intensity. At all-time points, anorexic patients showed lower hypothalamic activity compared with NA (P < 0.001) (T0: 585.57 ± 55.69 vs. 667.92 ± 33.18, respectively; T1: 536.50 ± 61.70 vs. 624.49 ± 55.51, respectively; T2: 556.44 ± 58.51 vs. 615.43 ± 71.50, respectively). Anorexic patients showed greater BOLD signal reduction during T0-T1 than NA (-8.5% vs. -6.80%, P < 0.001). Independently from the presence of anorexia, BOLD signals modification before and after oral challenge correlated with basal values of IL-1 and ghrelin (P < 0.001). CONCLUSIONS: Hypothalamic activity in A cancer patients is reduced respect to NA and responds differently to oral challenges. This suggests a central control of appetite dysregulation during cancer anorexia, before, and after oral intake.

Current tecniques and new perpectives research of magnetic resonance enterography in pediatric Crohn's disease.

Crohn's disease affects more than 500000 individuals in the United States, and about 25% of cases are diagnosed during the pediatric period. Imaging of the bowel has undergone dramatic changes in the past two decades. The endoscopy with biopsy is generally considered the diagnostic reference standard, this combination can evaluates only the mucosa, not inflammation or fibrosis in the mucosa. Actually, the only modalities that can visualize submucosal tissues throughout the small bowel are the computed tomography (CT) enterography (CTE) with the magnetic resonance enterography (MRE). CT generally is highly utilized, but there is growing concern over ionizing radiation and cancer risk; it is a very important aspect to keep in consideration in pediatric patients. In contrast to CTE, MRE does not subject patients to ionizing radiation and can be used to detect detailed morphologic information and functional data of bowel disease, to monitor the effects of medical therapy more accurately, to detect residual active disease even in patients showing apparent clinical resolution and to guide treatment more accurately.

Value of ultra-low-dose chest CT with iterative reconstruction for selected emergency room patients with acute dyspnea.

OBJECTIVE: To compare the diagnostic confidence between low-dose computed-tomography (LDCT) and ultra-low-dose CT (ULDCT) of the chest on a single source CT system (SSCT) for patients with acute dyspnoea. MATERIALS AND METHODS: One hundred thirty-three consecutive dyspnoeic patients referred from the emergency room (ER) were selected to undergo two sequential non-enhanced chest CT acquisitions: LDCT first acquisition (100kVp and 60mAs), followed by ULDCT (100kVp±20 and 10mAs). Images were reconstructed with sinogram affirmed reconstruction (SAFIRE). Objective and subjective image quality assessments were made. Two radiologists evaluated subjective image quality and the level of diagnostic confidence as certain or uncertain. RESULTS: The mean effective doses (ED) were 1.164±0.403 and 0.182±0.028mSv for LDCT and ULDCT, respectively. Objective image quality improved significantly on lung images of ULDCT compared with LDCT (p<0.05). Subjective image quality was rated excellent/good in 90% of patients with BMI=25kg/m(2) for ULDCT. The level of diagnostic confidence was "certain" in all cases for both radiologists with excellent inter-observer agreement (k=1). CONCLUSION: Chest ULDCT with SAFIRE on a SSCT allows a high level diagnostic confidence for the evaluation of selected acute dyspnoeic patients.

Are Second Trimester Apparent Diffusion Coefficient Values of the Short Uterine Cervix Associated with Impending Preterm Delivery?

Purpose To prospectively determine whether the apparent diffusion coefficient (ADC) of the cervix is associated with preterm delivery in asymptomatic patients with a sonographic cervical length of 15 mm or less and positive fetal fibronectin test results between 23 and 28 weeks of gestation. Materials and Methods The institutional review board approved this prospective hypotheses-generating study. A total of 30 pregnant women (mean gestational age, 26 weeks) with a sonographic short cervix (≤15 mm) underwent pelvic 1.5-T magnetic resonance (MR) imaging. Oblique sagittal diffusion-weighted images were obtained with b values of 0, 400, and 800 sec/mm(2). ADC values at MR imaging of the subglandular and stromal cervix and the difference between both were correlated to the interval to delivery. Receiver operating characteristic curve analysis was performed to obtain sensitivity and specificity of ADC values in association with delivery within 7 days. Results Eight (27%) of 30 patients delivered within 6 or 7 days after MR imaging (impending delivery group), and 22 (73%) of 30 patients delivered between 18 and 89 days after imaging (mean, 55 days) (late delivery group). Mean subglandular ADC and mean ADC difference were higher (P < .001) in patients with impending delivery than in those with late delivery ([2406.3 ± 166.0] × 10(-6) mm(2)/sec vs [1708.9 ± 108.1] × 10(-6) mm(2)/sec and [657.3 ± 129.9] × 10(-6) mm(2)/sec vs [69.2 ± 70.2] × 10(-6) mm(2)/sec, respectively). Subglandular ADC inversely correlated with the interval between MR imaging and delivery (r = -0.75). Receiver operating characteristic curve analysis of subglandular ADC revealed 100% sensitivity (95% confidence interval: 63.1, 100) and 100% specificity (95% confidence interval: 84.6, 100) in association with impending delivery with a 1921 × 10(-6) mm(2)/sec threshold. Stromal ADC and sonographic cervical length showed no difference between groups (P = .072 and P = .511, respectively). Conclusion Cervical subglandular ADC at MR imaging is associated with impending preterm birth in patients with a short sonographic cervix. (©) RSNA, 2016.

Diagnosis of Small-Bowel Diseases: Prospective Comparison of Multi-Detector Row CT Enterography with MR Enterography.

PURPOSE: To prospectively compare the accuracies of computed tomographic (CT) enterography and magnetic resonance (MR) enterography for the detection and characterization of small-bowel diseases. MATERIALS AND METHODS: The institutional review board approved the study protocol, and informed consent was obtained from all participants. From June 2009 to July 2013, 150 consecutive patients (81 men and 69 women; mean age, 38.8 years; range, 18-74 years), who were suspected of having a small-bowel disease on the basis of clinical findings and whose previous upper and lower gastrointestinal endoscopy findings were normal, underwent CT and MR enterography. Two independent readers reviewed CT and MR enterographic images for the presence of small-bowel diseases, for differentiating between inflammatory and noninflammatory diseases, and for extraenteric complications. The histopathologic findings of surgical (n = 23) and endoscopic (n = 32) biopsy specimens were used as the reference standard; the results of video-capsule endoscopy (n = 36) and clinical follow-up (n = 59) were used only to confirm the absence of small-bowel disease. RESULTS: MR and CT enterography were successfully performed in all 150 patients. Overall sensitivity, specificity, and accuracy, respectively, in identifying patients with small-bowel lesions were 75.9% (41 of 54), 94.8% (91 of 96), and 88.0% (132 of 150) for CT enterography and 92.6% (50 of 54), 99.0% (95 of 96), and 96.7% (145 of 150) for MR enterography. The sensitivity of MR enterography was significantly higher than that of CT enterography for the detection of both overall small-bowel diseases (P = .0159) and neoplastic diseases (P = .0412) but not for the detection of inflammatory diseases (P > .99) or noninflammatory and nonneoplastic diseases (P = .6171). CONCLUSION: MR enterography is more accurate than CT enterography in the detection of small-bowel diseases; MR enterography was more accurate in detecting neoplastic diseases in particular.

Giant Schmorl's Node may Cause High Uptake and Mimic a Bone Metastasis on (18)F-Choline Positron Emission Tomography/Computed Tomography.

Bone metastasis in prostate cancer are detected by choline positron emission tomography/computed tomography (PET/CT) with high sensitivity and specificity. We report the case of a patient with previous prostatectomy for prostate cancer who underwent F-choline PET/CT for a recent increased of prostate-specific antigen value and showed focal vertebral uptake suggestive for skeletal metastasis; magnetic resonance imaging revealed unexpectedly a Schmorl's node (SN). False positives on choline PET-CT caused by SN has not be reported in the literature and the present case highlights that this possibility should be considered in case of choline vertebral increased uptake in the patient with prostate cancer.

Magnetic resonance enterography, small-intestine contrast US, and capsule endoscopy to evaluate the small bowel in pediatric Crohn's disease: a prospective, blinded, comparison study.

BACKGROUND: Small-bowel (SB) disease is a severe clinical entity among the phenotypes of Crohn's disease (CD). OBJECTIVE: To assess sensitivity, specificity, and accuracy of magnetic resonance enterography (MRE), small-intestine contrast US (SICUS), and capsule endoscopy (CE) in the diagnosis of pediatric SB-CD. DESIGN: Prospective, blinded, comparison study. SETTING: Tertiary center for pediatric inflammatory bowel disease. PATIENTS: Children with known or suspected CD. Diagnosis of SB obstruction at SICUS or MRE excluded patients from the study. INTERVENTION: Patients underwent ileocolonoscopy, MRE, SICUS, and CE over a 7-day period. For the imaging evaluation, SB was divided into 3 segments: jejunum, proximal and mid ileum, and terminal ileum. MAIN OUTCOME MEASUREMENTS: The performance of each method was compared to a consensus reference standard for upper SB and to ileocolonoscopy for the terminal ileum. RESULTS: Twenty-five patients completed the study. In the jejunum, the sensitivity of SICUS and CE was 92%, which was not significantly higher than MRE (75%); the specificity of CE (61%) was significantly lower than that of MRE (P = .04). In the proximal and mid ileum, MRE and CE did not have significantly higher sensitivity (100%) than SICUS (80%), but CE was less specific (P > .05). At the terminal ileum, SICUS and MRE were slightly more sensitive than CE (94% vs. 81%); however, the latter was more specific. LIMITATIONS: Use of the consensus reference standard for upper SB. Small number of patients. CONCLUSION: SICUS, MRE, and CE are all effective options for imaging SB. An integrated use of different tools should be suggested to achieve a complete assessment of the SB in children with suspected or confirmed CD.

Stone disease in pregnancy: imaging-guided therapy.

Renal colic is the most frequent nonobstetric cause for abdominal pain and subsequent hospitalization during pregnancy. The physio-anatomical changes in the urinary tract and the presence of the fetus may complicate the clinical presentation and management of nephrolithiasis. Ultrasound (US) is the primary radiological investigation of choice. Magnetic resonance urography (MRU) and low-dose computed tomography (CT) have to be considered as a second- and third-line test, respectively. If a study that uses ionizing radiation has to be performed, the radiation dose to the fetus should be as low as possible. The initial management of symptomatic ureteric stones is conservative during pregnancy. Intervention will be necessary in patients who do not respond to conservative measures. Therefore, it is crucial to obtain a prompt and accurate diagnosis to optimize the management of these patients. Teaching Points • In pregnancy, renal colic is the most frequent nonobstetric cause for abdominal pain and hospitalization. • Magnetic resonance urography should be considered when ultrasound is nondiagnostic. • Low-dose CT should be considered as a last-line test during pregnancy.

Imaging for acute pelvic pain in pregnancy.

Acute pelvic pain in pregnancy presents diagnostic and therapeutic challenges. Standard imaging techniques need to be adapted to reduce harm to the foetus from X-rays because of their teratogenic and carcinogenic potential. Ultrasound remains the primary imaging investigation of the pregnant abdomen. Magnetic resonance imaging (MRI) has been shown to be useful in the diagnosis of gynaecological and obstetric problems during pregnancy and in the setting of acute abdomen during pregnancy. MRI overcomes some of the limitations of ultrasound, mainly the size of the gravid uterus. MRI poses theoretical risks to the foetus and care must be taken to minimise these with the avoidance of contrast agents. Teaching Points • Ultrasound and MRI are the preferred investigations for acute pelvic pain during pregnancy. • Ultrasound remains the primary imaging investigation because of availability and portability. • MRI helps differentiate causes of acute pelvic pain when ultrasound is inconclusive.

Noninflammatory conditions of the small bowel.

Magnetic resonance (MR) imaging has been playing an evolving role in evaluating noninflammatory small-bowel conditions, such as tumors and malabsorption syndrome. MR imaging has shown to be superior to other diagnostic methods in identifying tumors of the small bowel. MR enterography and MR enteroclysis are both valid for studying noninflammatory conditions of the small intestine, although MR enteroclysis may be considered the modality of choice because of its accuracy in the diagnosis of small-bowel neoplasms. Intraluminal and extraluminal MR findings, combined with contrast-agent enhancement and functional information, help to make an accurate diagnosis and consequently to characterize small-bowel diseases.

Magnetic resonance imaging of small bowel neoplasms.

Magnetic resonance (MR) imaging is rapidly increasing clinical acceptance to evaluate the small bowel and can be the initial imaging method to investigate small bowel diseases. MR examinations may provide the first opportunity to detect and characterize tumours of the small bowel. Intra- and extraluminal MR findings, combined with contrast enhancement and functional information, help to make an accurate diagnosis and consequently characterize small bowel neoplasms. MR enteroclysis should be recommended for the initial investigation in patients suspected of having small bowel tumours. In this article, the MR findings of primary small bowel neoplasms are described and the MR findings for the differential diagnosis are discussed.