The Role of Dual-Energy CT in the Study of Urinary Tract Tumors: Review of Recent Literature.

Urothelial cancers are often detected incidentally because of an exponential growth in medical cross-sectional imaging. Nowadays there is the need for improved lesion characterization to distinguish clinically significant tumors from benign conditions. The gold standard for diagnosis of bladder cancer is cystoscopy, while for upper tract urothelial cancer computed tomographic urography and flexible ureteroscopy are more appropriate modalities. Computed tomography (CT) is the cornerstone in the assessment of locoregional and distant disease, using a protocol with precontrastographic and postcontrastographic phases. In particular, renal pelvis, ureter and bladder lesions can be assessed during the urography phase in the acquisition protocol of the urothelial tumors. Multiphasic CT is associated with overexposure to ionising radiation and repeated infusion of iodinated contrast media, which can be problematic especially in certain types of patients (allergic, nephropathic, pregnant women and in paediatric age). Dual-energy CT can overcome these difficulties with a number of methods, for example, by reconstructing virtual noncontrast images from a single-phase examination with contrast medium. In this review of the recent literature, we would like to highlight the role of Dual-energy CT in the diagnosis of urothelial cancer, its potential in this setting and possible advantages related to it.

Primary Lymphoproliferative Lung Diseases: Imaging and Multidisciplinary Approach.

Lymphoproliferative lung diseases are a heterogeneous group of disorders characterized by primary or secondary involvement of the lung. Primary pulmonary lymphomas are the most common type, representing 0.5-1% of all primary malignancies of the lung. The radiological presentation is often heterogeneous and non-specific: consolidations, masses, and nodules are the most common findings, followed by ground-glass opacities and interstitial involvement, more common in secondary lung lymphomas. These findings usually show a prevalent perilymphatic spread along bronchovascular bundles, without a prevalence in the upper or lower lung lobes. An ancillary sign, such as a "halo sign", "reverse halo sign", air bronchogram, or CT angiogram sign, may be present and can help rule out a differential diagnosis. Since a wide spectrum of pulmonary parenchymal diseases may mimic lymphoma, a correct clinical evaluation and a multidisciplinary approach are mandatory. In this sense, despite High-Resolution Computer Tomography (HRCT) representing the gold standard, a tissue sample is needed for a certain and definitive diagnosis. Cryobiopsy is a relatively new technique that permits the obtaining of a larger amount of tissue without significant artifacts, and is less invasive and more precise than surgical biopsy.

Reproducibility of CT radiomic features in lung neuroendocrine tumours (NETs) patients: analysis in a heterogeneous population.

BACKGROUND: The aim is to find a correlation between texture features extracted from neuroendocrine (NET) lung cancer subtypes, both Ki-67 index and the presence of lymph-nodal mediastinal metastases detected while using different computer tomography (CT) scanners. METHODS: Sixty patients with a confirmed pulmonary NET histological diagnosis, a known Ki-67 status and metastases, were included. After subdivision of primary lesions in baseline acquisition and venous phase, 107 radiomic features of first and higher orders were extracted. Spearman's correlation matrix with Ward's hierarchical clustering was applied to confirm the absence of bias due to the database heterogeneity. Nonparametric tests were conducted to identify statistically significant features in the distinction between patient groups (Ki-67 < 3-Group 1; 3 ≤ Ki-67 ≤ 20-Group 2; and Ki-67 > 20-Group 3, and presence of metastases). RESULTS: No bias arising from sample heterogeneity was found. Regarding Ki-67 groups statistical tests, seven statistically significant features (p value < 0.05) were found in post-contrast enhanced CT; three in baseline acquisitions. In metastasis classes distinction, three features (first-order class) were statistically significant in post-contrast acquisitions and 15 features (second-order class) in baseline acquisitions, including the three features distinguishing between Ki-67 groups in baseline images (MCC, ClusterProminence and Strength). CONCLUSIONS: Some radiomic features can be used as a valid and reproducible tool for predicting Ki-67 class and hence the subtype of lung NET in baseline and post-contrast enhanced CT images. In particular, in baseline examination three features can establish both tumour class and aggressiveness.

Dual-Energy CT applications in urinary tract cancers: an update.

Urothelial tumours are the fourth most common cancer in the world and account for the majority of tumours involving the bladder. The symptom that often leads to diagnosis is the presence of haematuria. Diagnosis is made by cystoscopy, which is currently the gold standard in bladder cancer. Computed tomography (CT) performed with pre- and post-contrastographic phases is essential in order to assess the loco-regional and distant extension of disease. The diagnosis and staging of upper tract urothelial cancer (UTUC) are best done with computed tomography urography and flexible ureteroscopy (URS). In the acquisition protocol of this type of tumour, a urographic phase is mandatory, which allows for an accurate diagnostic assessment of the renal pelvis, ureter and bladder, especially in papillary forms. The use of multiple acquisition phases, especially in this type of patient who will have to perform follow-up CTs, leads to the problem of overexposure to ionising radiation, as well as the frequent administration of iodinated contrast medium. For this reason, in recent year, the focus has been put on advanced technologies such as dual-energy CT (DECT), that is a method that can offer some advantages for both radiologist and patient, in the diagnosis of cancer and, in particular, urinary tract disease.

NAVIGATOR: an Italian regional imaging biobank to promote precision medicine for oncologic patients.

NAVIGATOR is an Italian regional project boosting precision medicine in oncology with the aim of making it more predictive, preventive, and personalised by advancing translational research based on quantitative imaging and integrative omics analyses. The project's goal is to develop an open imaging biobank for the collection and preservation of a large amount of standardised imaging multimodal datasets, including computed tomography, magnetic resonance imaging, and positron emission tomography data, together with the corresponding patient-related and omics-related relevant information extracted from regional healthcare services using an adapted privacy-preserving model. The project is based on an open-source imaging biobank and an open-science oriented virtual research environment (VRE). Available integrative omics and multi-imaging data of three use cases (prostate cancer, rectal cancer, and gastric cancer) will be collected. All data confined in NAVIGATOR (i.e., standard and novel imaging biomarkers, non-imaging data, health agency data) will be used to create a digital patient model, to support the reliable prediction of the disease phenotype and risk stratification. The VRE that relies on a well-established infrastructure, called D4Science.org, will further provide a multiset infrastructure for processing the integrative omics data, extracting specific radiomic signatures, and for identification and testing of novel imaging biomarkers through big data analytics and artificial intelligence.

Granulomatous Prostatitis, the Great Mimicker of Prostate Cancer: Can Multiparametric MRI Features Help in This Challenging Differential Diagnosis?

Clinico-radiological presentation of granulomatous prostatitis (GP) is quite similar to cancer, and differential diagnosis can be very challenging. The study aims to highlight GP features based on clinical findings and multiparametric magnetic resonance imaging (mpMRI) characteristics. We retrospectively reviewed eleven patients from a cohort undergoing targeted biopsy between August 2019 and August 2021. Retrospective data including serum prostate-specific antigen (PSA) levels, PSA density and mpMRI findings were collected. Histopathology revealed seven cases of non-specific GP and four cases of specific GP as a result of intravesical Bacillus Calmette-Guérin (BCG) instillation. All lesions showed low signal intensity in T2w images, restricted diffusivity with hyperintensity in Diffusion-Weighted Imaging (DWI) and low Apparent Diffusion Coefficient (ADC) values. In Dynamic Contrast-Enhanced (DCE) imaging, the enhancement was high-peak and persistent in the majority of cases, especially in BCG-GPs. Moreover, almost all those latter lesions showed avascular core and peripheral rim enhancement. All areas identified on mpMRI were assessed with high to very high suspicion to hold prostate cancer (PIRADS v2.1 scores 4-5). Despite recent advances in imaging modalities and serological investigations, it is currently still a challenge to identify granulomatous prostatitis. Histopathology remains the gold standard in disease diagnosis. However, a differential diagnosis should be considered in patients with prior treatment with BCG.

CT-urography: a nationwide survey by the Italian Board of Urogenital Radiology.

Computed tomography-urography is currently the imaging modality of choice for the assessment of the whole urinary tract, giving the possibility to detect and characterize benign and malignant conditions. In particular, computed tomography-urography takes advantage from an improved visualization of the urinary collecting system due to acquisition of delayed scan obtained after excretion of intravenous contrast medium from the kidneys. Nevertheless, the remaining scans are of great help for identification, characterization, and staging of urological tumors. Considering the high number of diseases, urinary segment potentially involved and patients' features, scanning protocols of computed tomography-urography largely vary from one clinical case to another as well as selection and previous preparation of the patient. According to the supramentioned considerations, radiation exposure is also of particular concern. Italian radiologists were asked to express their opinions about computed tomography-urography performance and about its role in their daily practice through an online survey. This paper collects and summarizes the results.

Contrast-enhanced ultrasound (CEUS) imaging for active surveillance of small renal masses.

PURPOSE: To assess the safety and efficacy of contrast-enhanced ultrasound (CEUS) imaging for monitoring small (< 4 cm) renal masses (SRM) in patients undergoing active surveillance (AS). METHODS: We retrospectively selected all consecutive patients with SRMs who underwent AS for at least 6 months at our Institution between January 2014 and December 2018. CEUS imaging was performed by two experienced genitourinary radiologists at established time points. The accuracy of CEUS for monitoring SRM size was compared with that of CT scan. For solid SRMs, four enhancement patterns (EP) were recorded. Radiological progression was defined as SRM growth rate ≥ 5 mm/year. RESULTS: Overall, 158/1049 (15.1%) patients with SRMs underwent AS. At a median follow-up of 25 months (IQR 13-39), no patient died due to renal cell carcinoma (RCC). No patients experienced CEUS-related adverse events. There was a large variability in the pattern of growth of SRMs (overall median growth rate: 0.40 mm/year), with 9.5% of SRMs showing radiological progression. The median SRM size was comparable between CEUS and CT scan examinations at all time points. The vast majority (92.7%) of SRMs did not show a change in their EP over time; and there was no association between the SRM's EP and radiological progression or SRM size. Overall, 43 (27.2%) patients underwent delayed intervention (DI); median SRM size, and median growth rate were significantly higher in these patients as compared to those continuing AS. CONCLUSION: In experienced hands, CEUS is a safe and effective strategy for active monitoring of SRMs in well-selected patients undergoing AS.

Machine and Deep Learning Prediction Of Prostate Cancer Aggressiveness Using Multiparametric MRI.

Prostate cancer (PCa) is the most frequent male malignancy and the assessment of PCa aggressiveness, for which a biopsy is required, is fundamental for patient management. Currently, multiparametric (mp) MRI is strongly recommended before biopsy. Quantitative assessment of mpMRI might provide the radiologist with an objective and noninvasive tool for supporting the decision-making in clinical practice and decreasing intra- and inter-reader variability. In this view, high dimensional radiomics features and Machine Learning (ML) techniques, along with Deep Learning (DL) methods working on raw images directly, could assist the radiologist in the clinical workflow. The aim of this study was to develop and validate ML/DL frameworks on mpMRI data to characterize PCas according to their aggressiveness. We optimized several ML/DL frameworks on T2w, ADC and T2w+ADC data, using a patient-based nested validation scheme. The dataset was composed of 112 patients (132 peripheral lesions with Prostate Imaging Reporting and Data System (PI-RADS) score ≥ 3) acquired following both PI-RADS 2.0 and 2.1 guidelines. Firstly, ML/DL frameworks trained and validated on PI-RADS 2.0 data were tested on both PI-RADS 2.0 and 2.1 data. Then, we trained, validated and tested ML/DL frameworks on a multi PI-RADS dataset. We reported the performances in terms of Area Under the Receiver Operating curve (AUROC), specificity and sensitivity. The ML/DL frameworks trained on T2w data achieved the overall best performance. Notably, ML and DL frameworks trained and validated on PI-RADS 2.0 data obtained median AUROC values equal to 0.750 and 0.875, respectively, on unseen PI-RADS 2.0 test set. Similarly, ML/DL frameworks trained and validated on multi PI-RADS T2w data showed median AUROC values equal to 0.795 and 0.750, respectively, on unseen multi PI-RADS test set. Conversely, all the ML/DL frameworks trained and validated on PI-RADS 2.0 data, achieved AUROC values no better than the chance level when tested on PI-RADS 2.1 data. Both ML/DL techniques applied on mpMRI seem to be a valid aid in predicting PCa aggressiveness. In particular, ML/DL frameworks fed with T2w images data (objective, fast and non-invasive) show good performances and might support decision-making in patient diagnostic and therapeutic management, reducing intra- and inter-reader variability.

Radiofrequency ablation (RFA) of T1a renal cancer with externally cooled multitined expandable electrodes.

INTRODUCTION: To retrospectively evaluate the mid-term outcomes of percutaneous radiofrequency ablation (RFA) with multitined expandable electrodes externally cooled with saline solution in patients with T1a renal cell carcinoma (RCC). MATERIALS AND METHODS: In this retrospective study, we evaluated 39 RCC in 35 patients treated with CT-guided RFA in 41 procedures (2011-2017). All patients were staged T1a, N0, M0 prior to RFA. Mean tumor size was 24.48 mm. A 4-tined expandable RFA electrode cooled with pump-circulating saline was used. Efficacy was evaluated verifying complete tumor necrosis (no contrast enhancement on imaging) at the end of the procedure and on subsequent controls. Follow-up observation period was 5 years. Minor/major complications, hospitalization days, serum creatinine and GFR pre- and post-RFA (compared using paired t test) and post-operative pain (evaluated with NRS after treatment) were considered as safety indicators. Overall survival was also calculated (Kaplan-Meier method). RESULTS: Of 35 patients, 30/35 had 1 treatment (primary effectiveness rate 86%), 4/35 had 2 treatments and 1/35 had 3 treatments for residual disease. There were no relapses and no mid-long-term complications; 3 minor (8%) and 1 major (2.7%) complications during perioperative period were reported. Mean before and after RFA serum creatinine rates were, respectively, 1.08 mg/dl and 1.11 mg/dl (p value: 0.4117). NRS median value is 0.8. Hospitalization days median value is [2.8 ± 1.9] days. 91.4% of all patients survived, with a median overall survival time of 65 months. CONCLUSIONS: Mid-term results show that CT-guided RFA with multitined expandable electrodes externally cooled with saline solution is an effective and safe treatment in patients with RCC-staged T1aN0M0. Data reported in our study are in line with data reported in the literature from patients treated with other devices.

Ultrasound findings in urogenital schistosomiasis: a pictorial essay.

Urogenital schistosomiasis is a parasitic disease caused by S. haematobium which is endemic in tropical and sub-tropical areas but is increasingly diagnosed in temperate non-endemic countries due to migration and international travels. Early identification and treatment of the disease are fundamental to avoid associated severe sequelae such as bladder carcinoma, hydronephrosis leading to kidney failure and reproductive complications. Radiologic imaging, especially through ultrasound examination, has a fundamental role in the assessment of organ damage and follow-up after treatment. Imaging findings of urinary tract schistosomiasis are observed mainly in the ureters and bladder. The kidneys usually appear normal until a late stage of the disease.

Surgical margin follow-up after nephron-sparing surgery: the possible role of CEUS.

PURPOSE: To evaluate the possible role of CEUS in the management of patients who underwent nephron-sparing surgery (NSS) and presented questionable findings on the surgical margins at the CECT follow-up exam. METHODS: In our retro-prospective study, we included 952 patients with small renal masses (SRMs) treated with NSS between 2012 and 2015 and followed with CECT for at least 3 years at Careggi University Hospital. Twenty-two of them presented solid masses on the site of surgery with questionable enhancement at CECT and were further studied with CEUS. This examination was followed by a quantitative analysis of the enhancement pattern. RESULTS: Out of the 22 masses, 18 were considered possible granulomas, presenting slow wash-in and low enhancement peaks compared to the surrounding parenchyma and persistent delayed wash-out at CEUS. Four lesions presented a suspicious malignant enhancement pattern, with rapid wash-in, high peak and rapid wash-out. In accordance with instructions from the urologist, the first group of 18 patients was strictly monitored, revealing that the mass dimensions and enhancement pattern were stable for at least 3 years of follow-up, while the other 4 patients underwent a second intervention and their masses were confirmed as tumor recurrence at the histopathological evaluation. CONCLUSIONS: CEUS can play a key role in the surgical margin follow-up after NSS when a suspicious enhancing mass is detected by CECT, giving an accurate depiction of the enhancement pattern and thus helping the clinician in the management of the patient.

Correction to: Rare case of an upper urinary tract carcinoma (UTUC) in renal pelvis and ureter associated to renal vein thrombosis: diagnostic imaging with CECT, MRI and CEUS.

Unfortunately, the first name and family names of all the authors have incorrectly been swapped and published in original article.

Multi-detector computed tomography in the diagnosis and characterization of adrenal gland traumatic injuries.

Adrenal gland injuries after a blunt abdominal trauma are rare events and represent important indicators for severe trauma. Multidetector CT evolution with high volumetric resolution and fast acquisition with the use of multiplanar reformatted (MPR) visualization allows for an accurate and fast diagnosis of the adrenal gland for post-traumatic pathologies. While, before its introduction the diagnosis was made mainly postmortem or during surgery. Adrenal injuries are unilateral up to 90% of the cases involving most commonly the right gland; thoracoabdominal organs injuries are often also associated. Bilateral adrenal lesions are asymptomatic, potentially leading to the development of acute adrenal insufficiency. The purpose of the present review was to determine the prevalence, the mechanism of injury and the different CT appearances of adrenal trauma. Prognosis and management of adrenal injury will also be reviewed.

Screen-detected multiple primary lung cancers in the ITALUNG trial.

Occurrence of multiple primary lung cancers (MPLC) in individuals undergoing low-dose computed tomography (LDCT) screening has not been thoroughly addressed. We investigated MPLC in subjects recruited in the ITALUNG randomized clinical trial. Cases of cytologically/histologically proven MPLC detected at screening LDCT or follow-up CT were selected and pathologically re-evaluated according to the WHO 2015 classification. Overall 16 MPLC were diagnosed at screening LDCT (n=14, all present at baseline) or follow-up CT (n=2) in six subjects (4 in one subject, 3 in two and 2 in three subjects), representing 0.43% of the 1,406 screenees and 15.8% of the 38 subjects with at least one screen-detected primary lung cancer. MPLC included 9 adenocarcinomas in three subjects and a combination of 7 different tumour histotypes in three subjects. MPLC, mostly adenocarcinomas, are not uncommon in smokers and ex-smokers with at least one LDCT screen detected primary lung cancer.

Circulating tumor cells and microemboli can differentiate malignant and benign pulmonary lesions.

The presence of circulating tumor cells (CTC) or microemboli (CTM) in the peripheral blood can theoretically anticipate malignancy of solid lesions in a variety of organs. We aimed to preliminarily assess this capability in patients with pulmonary lesions of suspected malignant nature. We used a cell-size filtration method (ScreenCell) and cytomorphometric criteria to detect CTC/CTM in a 3 mL sample of peripheral blood that was taken just before diagnostic percutaneous CT-guided fine needle aspiration (FNA) or core biopsy of the suspicious lung lesion. At least one CTC/CTM was found in 47 of 67 (70%) patients with final diagnoses of lung malignancy and in none of 8 patients with benign pulmonary nodules. In particular they were detected in 38 (69%) of 55 primary lung cancers and in 9 (75%) of 12 lung metastases from extra-pulmonary cancers. Sensitivity of CTC/CTM presence for malignancy was 70.1% (95%CI: 56.9-83.1%), specificity 100%, positive predictive value 100% and negative predictive value 28.6% (95%CI: 11.9-45.3%). Remarkably, the presence of CTC/CTM anticipated the diagnosis of primary lung cancer in 3 of 5 patients with non-diagnostic or inconclusive results of FNA or core biopsy, whereas CTC/CTM were not observed in 1 patient with sarcoidosis and 1 with amarthocondroma. These results suggest that presently, due to the low sensitivity, the search of CTC/CTM cannot replace CT guided percutaneous FNA or core biopsy in the diagnostic work-up of patients with suspicious malignant lung lesions. However, the high specificity may as yet indicate a role in cases with non-diagnostic or inconclusive FNA or core biopsy results that warrants to be further investigated.

Prevalence and number of circulating tumour cells and microemboli at diagnosis of advanced NSCLC.

PURPOSE: Timing and magnitude of blood release of circulating tumour cells (CTC) and circulating tumour microemboli (CTM) from primary solid cancers are uncertain. We investigated prevalence and number of CTC and CTM at diagnosis of advanced non-small cell lung cancer (NSCLC). METHODS: Twenty-eight consecutive patients with suspected stage III-IV lung cancer gave consent to provide 15 mL of peripheral blood soon before diagnostic CT-guided fine-needle aspiration biopsy (FNAB). CTC and CTM (clusters of ≥3 CTC) were isolated by cell size filtration (ScreenCell), identified and counted by cytopathologists using morphometric criteria and (in 6 cases) immunostained for vimentin. RESULTS: FNAB demonstrated NSCLC in 26 cases. At least one CTC/3 mL blood (mean 6.8 ± 3.7) was detected in 17 (65 %) and one CTM (mean 4.5 ± 3.3) in 15 (58 %) of 26 NSCLC cases. No correlation between number of CTC or CTM and tumour type or stage was observed. Neoplastic cells from both FNA and CTC/CTM were positive for vimentin but heterogeneously. CONCLUSIONS: CTC can be detected in two-thirds and CTM in more than half of patients with advanced NSCLC at diagnosis. Reasons underlying lack of CTC and CTM in some advanced lung cancers deserve further investigations.

Lung cancer associated with cystic airspaces.

OBJECTIVE: This study aimed to define computed tomographic morphologic features of lung cancer associated with cystic airspaces, their modifications in serial computed tomographic scans, and 18F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography uptake. METHODS: Computed tomographic scans and 18F-FDG positron emission tomography in 24 patients with lung cancer (17 adenocarcinomas, 7 squamous cell carcinomas, 12 stage I and 12 stage II to IV) associated with cystic airspaces were reviewed. RESULTS: Mean diameter of airspace was initially 17.6 mm (range, 5-30 mm), and 4 morphologic patterns were recognized: solid nodule protruding externally (type I, n = 5) or internally (type II, n = 4) from the cyst wall; circumferential thickening of the cyst wall (type III, n = 8); and tissue intermixed within clusters of cysts (type IV, n = 7). With tumor growth, airspace size decreased in 9, increased in 6, and was unchanged in 9 cases. Five cases evolved from type III to type I, and 5 lesions became completely solid. 18F-fluoro-2-deoxy-D-glucose uptake was initially absent to mild in 7 and moderate to marked in 14 lesions. CONCLUSIONS: Progressive wall thickening or appearance/increase of a nodule inside or outside a cystic airspace should raise suspicion of lung cancer irrespective of FDG uptake.