Cornerstones of CT urography: a shared document by the Italian board of urogenital radiology.

CT urography is a single term used to refer to different scanning protocols that can be applied for a number of clinical indications. If, on the one hand, this highlights the role of the radiologist in deciding the most suitable technique to perform according to the patient's needs, on the other hand, a certain confusion may arise due to the different technical and clinical variables that have to be taken into account. This has been well demonstrated by a previous work based on an online questionnaire administered to a population of Italian radiologists that brought out similarities as well as differences across the national country. Defining precise guidelines for each clinical scenario, although desirable, is a difficult task to accomplish, if not even unfeasible. According to the prementioned survey, five relevant topics concerning CT urography have been identified: definition and clinical indications, opacification of the excretory system, techniques, post-processing reconstructions, and radiation dose and utility of dual-energy CT. The aim of this work is to deepen and share knowledge about these main points in order to assist the radiology in the daily practice. Moreover, a synopsis of recommendations agreed by the Italian board of genitourinary imaging is provided.

Gas-containing renal stones: a red flag for renal infection.

BACKGROUND: Gas in the renal excretory system is described as a consequence of recent procedures but it can be a sign of severe conditions such as fistulas or infections; however, gas-containing renal stones are only rarely encountered. PURPOSE: To describe the association of gas-containing renal stones and urinary tract infection. MATERIAL AND METHODS: We performed a retrospective evaluation of the clinical and imaging findings in a series of six patients with gas-containing renal stones and compared our findings with those of patients with gas-containing renal stones reported in the literature. Urine and stone cultures were used as a diagnostic standard for urinary tract infection. RESULTS: Including the present series, there is a total of 21 patients with gas-containing renal stones in the literature. Based on clinical presentation, urinary tract infection could be suspected in 10 (57%) patients, while urine and/or stone cultures showed infection in 18 of 19 (95%) patients, with only one case with no bacterial growth in both (5%); in the remaining patient the information was not available. CONCLUSION: Gas-containing renal stones are a rarely reported entity usually diagnosed with computed tomography. They are a radiological sign often associated with urinary tract infection that can also be encountered in patients with non-specific renal symptoms.

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.

A novel pathway to detect muscle-invasive bladder cancer based on integrated clinical features and VI-RADS score on MRI: results of a prospective multicenter study.

PURPOSE: To determine the clinical, pathological, and radiological features, including the Vesical Imaging-Reporting and Data System (VI-RADS) score, independently correlating with muscle-invasive bladder cancer (BCa), in a multicentric national setting. METHOD AND MATERIALS: Patients with BCa suspicion were offered magnetic resonance imaging (MRI) before trans-urethral resection of bladder tumor (TURBT). According to VI-RADS, a cutoff of ≥ 3 or ≥ 4 was assumed to define muscle-invasive bladder cancer (MIBC). Trans-urethral resection of the tumor (TURBT) and/or cystectomy reports were compared with preoperative VI-RADS scores to assess accuracy of MRI for discriminating between non-muscle-invasive versus MIBC. Performance was assessed by ROC curve analysis. Two univariable and multivariable logistic regression models were implemented including clinical, pathological, radiological data, and VI-RADS categories to determine the variables with an independent effect on MIBC. RESULTS: A final cohort of 139 patients was enrolled (median age 70 [IQR: 64, 76.5]). MRI showed sensitivity, specificity, PPV, NPV, and accuracy for MIBC diagnosis ranging from 83-93%, 80-92%, 67-81%, 93-96%, and 84-89% for the more experienced readers. The area under the curve (AUC) was 0.95 (0.91-0.99). In the multivariable logistic regression model, the VI-RADS score, using both a cutoff of 3 and 4 (P < .0001), hematuria (P = .007), tumor size (P = .013), and concomitant hydronephrosis (P = .027) were the variables correlating with a bladder cancer staged as ≥ T2. The inter-reader agreement was substantial (k = 0.814). CONCLUSIONS: VI-RADS assessment scoring proved to be an independent predictor of muscle-invasiveness, which might implicate a shift toward a more aggressive selection approach of patients' at high risk of MIBC, according to a novel proposed predictive pathway.

Are Urologists Ready for Interpretation of Multiparametric MRI Findings? A Prospective Multicentric Evaluation.

Aim: To assess urologists' proficiency in the interpretation of multiparametric magnetic resonance imaging (mpMRI). Materials and Methods: Twelve mpMRIs were shown to 73 urologists from seven Italian institutions. Responders were asked to identify the site of the suspicious nodule (SN) but not to assign a PIRADS score. We set an a priori cut-off of 75% correct identification of SN as a threshold for proficiency in mpMRI reading. Data were analyzed according to urologists' hierarchy (UH; resident vs. consultant) and previous experience in fusion prostate biopsies (E-fPB, defined as <125 vs. ≥125). Additionally, we tested for differences between non-proficient vs. proficient mpMRI readers. Multivariable logistic regression analyses (MVLRA) tested potential predictors of proficiency in mpMRI reading. Results: The median (IQR) number of correct identifications was 8 (6−8). Anterior nodules (number 3, 4 and 6) represented the most likely prone to misinterpretation. Overall, 34 (47%) participants achieved the 75% cut-off. When comparing consultants vs. residents, we found no differences in terms of E-fPB (p = 0.9) or in correct identification rates (p = 0.6). We recorded higher identification rates in urologists with E-fBP vs. their no E-fBP counterparts (75% vs. 67%, p = 0.004). At MVLRA, only E- fPB reached the status of independent predictor of proficiency in mpMRI reading (OR: 3.4, 95% CI 1.2−9.9, p = 0.02) after adjusting for UH and type of institution. Conclusions: Despite urologists becoming more familiar with interpretation of mpMRI, their results are still far from proficient. E-fPB enhances the proficiency in mpMRI interpretation.

sABLATE: a simplified ABLATE score for prediction of complications and outcome in percutaneous thermal ablation of renal lesions.

The aim of the study is to evaluate the performance of a simplified ABLATE score (sABLATE) in predicting complications and outcome with respect to RENAL, mRENAL, and ABLATE scores. This study included 136 renal lesions in 113 patients (M:F ratio = 2.5; mean age 70.8 years). 98 tumors underwent cryoablation at San Raffaele hospital between 01/2015 and 03/2020, while 37 underwent microwave ablation at San Paolo or Policlinico hospitals between 07/2016 and 03/2020. RENAL, mRENAL, ABLATE, and sABLATE scores were calculated using pre-procedural imaging. Data regarding complications and follow-up were registered. Mann-Whitney U test, ROC analyses, and logistic regression analyses were used for complications. Cox-regression analyses were performed for outcome. Mean tumor diameter was 23.2 mm. Mean and median RENAL, mRENAL, ABLATE, and sABLATE scores were 6.8 and 7, 6.9 and 7, 5.3, and 5, and 3.5 and 3, respectively. During a mean follow-up of 21.9 months (range 1-73), we registered 7 complications, 3 cases of residual disease, and 10 local tumor progressions. Mann-Whitney U test p values for complications for RENAL, mRENAL, ABLATE, and sABLATE were 0.51, 0.49, 0.66, and 0.056, respectively. ROC analyses for complications showed an AUC for RENAL, mRENAL, ABLATE, and sABLATE of 0.57, 0.57, 0.55, and 0.71, respectively. Regarding outcome, HR and p values of Cox-regression analyses were 1.30 and 0.36 for RENAL, 1.33 and 0.35 for mRENAL, 2.16 and 0.01 for ABLATE, 2.29 and 0.004 for sABLATE. sABLATE was the only score close to significance for complications, representing a progress even if not definitive. Regarding outcome, ABLATE confirmed its value, and sABLATE maintained validity despite being a simplification.

ABLATE: a score to predict complications and recurrence rate in percutaneous treatments of renal lesions.

RENAL score has been validated on predicting adverse events and relapses in percutaneous treatments of renal lesions. To better fit interventional issues a modified score (mRENAL) has been introduced, but the only difference from the RENAL score is on the dimensional parameter. However, it remains of surgical derivation while a specific interventional score is missing. This study aims to obtain a specific score (ABLATE) to better quantify the risk of complications and relapses in percutaneous kidney ablation procedures compared to the existing surgical scores. Taking inspiration from previous papers, a score was built to quantify the real difficulties faced in percutaneous treatment of renal lesions. The ABLATE score was used on 71 cryoablations to evaluate its predictivity of complications and relapses. Logistic regression was used to predict complication incidence; Cox-regression was used for relapses; ROC analysis was used to evaluate the accuracy of the different scores. Between January 2014 and November 2019, 71 lesions in 68 patients were treated. Overall, malignant histology was found in 62 lesions (87.3%). Mean and median RENAL, mRENAL, and ABLATE scores were 7.04 and 7, 7.19 and 7, and 5.11 and 4, respectively. Out of 71 treatments, we experienced 3 bleeding with anemia (4.2%), only 2 of which needed further treatment (2.82%). The mean and median RENAL, mRENAL, and ABLATE scores in those with complications were 7.66 and 7.01 (p = 0.69), 8.0 and 7.1 (p = 0.54), and 6.6 and 5.0 (p = 0.38), respectively. Out of 62 malignant lesions, we experienced 2 persistent and 6 recurrent lesions (3.2% and 8.4%, respectively). At Cox-regression analyses, mABLATE score outperformed both RENAL and mRENAL scores in predicting recurrences (HR 1.48; p < 0.001 vs. 1.41; p = 0.1 vs. 1.38: p = 0.07, respectively). The ABLATE score showed to be a better predictor of relapses than RENAL and mRENAL. The small number of complications conditioned a lack of statistic power on complications for all the scores. At the moment to quantify the risks in percutaneous kidney ablation procedures, surgical scores are used. A specific score better performs this task.

Percutaneous Microwave Ablation Versus Cryoablation in the Treatment of T1a Renal Tumors.

PURPOSE: Radiofrequency and cryoablation (Cryo) are the most widely used techniques for the treatment of T1a renal tumors in non-surgical candidates, yet microwave ablation (MWA) has been gaining popularity. In this study, we tested the hypothesis that MWA has comparable safety and efficacy to Cryo in the treatment of selected T1a renal masses. MATERIALS AND METHODS: A retrospective comparative analysis of two patient cohorts was carried out on 83 nodules in 72 consecutive patients treated using image-guided percutaneous ablation with either Cryo or MWA. Patient demographics, tumor histology and characteristics, technical success, procedure time, adverse events and complications, nephrometry score (mRENAL) and renal function were evaluated. Local recurrence was evaluated at 1, 6, 12 and 18-24 months. RESULTS: Fifty-one nodules were treated with Cryo and 32 with MWA (44 and 28 patients, respectively). No statistical differences were observed following Cryo or MWA in median tumor size (p = 0.6), mRENAL (p = 0.1) or technical success (p = 0.8). Median procedure time was significantly lower using microwave ablation (p = 0.003). Median follow-up time was similar in the two groups (22 and 20 months, respectively). Occurrence of complications did not differ (Cryo 5/51, MWA 2/32; p = 0.57), and probability of complications or technical success adjusted for mRENAL did not reach statistical significance (p = 0.6). Renal function was preserved in all patients regardless of techniques. Disease recurrence was observed in 3/47 and in 1/30 treated nodules in the Cryo and MWA groups, respectively, without reaching statistical significance (p = 0.06). CONCLUSION: In the patient population studied, MWA showed comparable safety and efficacy relative to Cryo. LEVEL OF EVIDENCE: Level 3, Non-randomized cohort study.

Association Between Prostate Imaging Reporting and Data System (PI-RADS) Score for the Index Lesion and Multifocal, Clinically Significant Prostate Cancer.

BACKGROUND: The ability to identify clinically significant prostate cancer (csPCa) has dramatically improved with the introduction of multiparametric magnetic resonance imaging (mpMRI). Given the growing interest in targeted biopsy and focal therapy, improving our knowledge on the relationship between mpMRI parameters and the ability to predict csPCa multifocality is mandatory. OBJECTIVE: To assess whether the Prostate Imaging Reporting and Data System (PI-RADS) score for the index lesion (IL) may predict multifocal csPCa undetected by mpMRI. DESIGN, SETTING, AND PARTICIPANTS: The study included 343 patients who underwent mpMRI of the prostate with subsequent biopsy between 2014 and 2017 at a single tertiary care referral centre. INTERVENTION: Lesions with a PI-RADS v.2 score ≥2 detected at mpMRI (IL) were targeted with a fusion biopsy (Bx) approach (mpMRI-Bx). Moreover, each patient underwent a random extended transrectal ultrasound-guided biopsy (TRUS-Bx) during the same session. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: csPCa outside the IL was defined as disease detected at TRUS-Bx with a Gleason score (GS)≥3+4 and equal to or greater than the GS for the IL. The extent of csPCa detected in target and random cores was reported and stratified according to the GS and PI-RADS score for the IL. The probability of diagnosing csPCa outside the IL according to the PI-RADS score was also assessed in multivariable logistic regression analyses (MVA) after accounting for confounders. RESULTS AND LIMITATIONS: The detection rate for csPCa outside the IL was 30%. The detection rate for csPCa at TRUS-Bx was 8% for PI-RADS 2, 15% for PI-RADS 3, 36% for PI-RADS 4, and 58% for PI-RADS 5 lesions (p=0.03). Overall, the median length of csPCa found at TRUS-Bx and thus missed at mpMRI was 2.6mm. However, the length significantly increased with PI-RADS score for the IL, and was 1.8, 2.3, 2.8, and 3.8mm for PI-RADS 2, 3, 4, and 5 lesions, respectively (p=0.03). On MVA, PI-RADS 4 (odds ratio [OR] 7.6; p=0.008) and PI-RADS 5 scores (OR 17.3; p<0.001) were independent predictors of the presence of csPCa outside the IL. The study is limited by its retrospective design. CONCLUSIONS: Overall, the accuracy of mpMRI in identifying multifocal csPCa is poor, missing low-volume csPCa in approximately 30% of patients. Moreover, the rate and the extent of csPCa undetected by mpMRI significantly increased with the PI-RADS score for the IL, which can thus be considered a proxy for tumour multifocality. PATIENT SUMMARY: The accuracy of multiparametric magnetic resonance imaging in identifying prostate cancer multifocality is poor. False negative findings were highly related to the PI-RADS score of the index lesion. These findings raise concerns about the indication for targeting the index lesion only when considering prostate biopsy and focal approaches.

Not All Multiparametric Magnetic Resonance Imaging-targeted Biopsies Are Equal: The Impact of the Type of Approach and Operator Expertise on the Detection of Clinically Significant Prostate Cancer.

BACKGROUND: The extensive use of multiparametric magnetic resonance imaging (mpMRI) has led to an even more widespread use of different targeted biopsy techniques and approaches. The best way of performing targeted biopsies and the effect of operator expertise have still to be defined. OBJECTIVE: To compare the rate of detection of clinically significant prostate cancer (csPCa) of different mpMRI targeted approaches and to assess the role of operator expertise in the detection of csPCa. DESIGN, SETTING, AND PARTICIPANTS: We included 244 consecutive patients who underwent both 12-core transrectal ultrasound (TRUS) biopsy and mpMRI targeted biopsy with either a cognitive biopsy (CB) or fusion biopsy (FB) approach during the same session between 2013 and 2016 at a single tertiary referral centre. INTERVENTION: All men underwent 1.5-T mpMRI with an endorectal coil. All biopsies were performed by three operators as their first cases of targeted biopsy. Lesions with a Prostate Imaging Recording and Data System (PI-RADS) v.2 score of ≥3 detected at mpMRI were targeted. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: csPCa was defined as disease with a Gleason score at biopsy of ≥7. Operator expertise was coded as the progressive number of targeted biopsies performed by each physician. Multivariable logistic regression analyses (MVA) were used to assess the association between the targeted biopsy technique (FB vs CB) and operator expertise for detection of csPCa. Covariates consisted of prostate-specific antigen, prostate volume, PI-RADS v.2 (3 vs >3), number of targeted cores per MRI lesion, and digital rectal examination (negative vs positive). The same analyses were performed for patients undergoing FB only after accounting for the FB approach (transrectal vs transperineal). A lowess smoothing weighted function was used to graphically assess the effect of operator expertise on the probability of detecting csPCa, after accounting for all confounders. RESULTS AND LIMITATIONS: Overall, 157 patients (64%) underwent FB and 87 (36%) underwent CB. The overall csPCa detection rate was 58% for FB and 45% for CB (p=0.07). A significantly higher rate of csPCa detection in targeted samples was observed for FB compared to CB (57% vs 36%; p=0.002). On MVA, FB and operator expertise were significantly associated with a higher probability of csPCa detection in targeted samples (odds ratio [OR] 2.4 and 1.7, respectively; both p≤0.03). When the same analyses were repeated for patients undergoing FB, operator expertise remained an independent predictor of csPCa detection (OR 1.9; p=0.004). An increase in the probability of detecting csPCa with the number of procedures performed was observed after accounting for all confounders. CONCLUSIONS: We demonstrated that FB had higher detection rate than CB for csPCa. Moreover, operator expertise was significantly associated with higher detection rates for csPCa. PATIENT SUMMARY: When different targeted biopsy techniques were compared, fusion biopsy provided a higher detection rate compared to cognitive biopsy for clinically significant prostate cancer (csPCa). Moreover, we found that operator expertise was an important predictor of the detection of csPCa, regardless of the procedure used.

Magnetic resonance imaging for localization of prostate cancer in the setting of biochemical recurrence.

The clinical suspicion of local recurrence of prostate cancer after radical treatment is based on the onset of biochemical failure. The use of multiparametric magnetic resonance imaging (MRI) for prostate cancer has increased over recent years, mainly for detection, staging, and active surveillance. However, suspicion of recurrence in the set of biochemical failure is becoming a significant reason for clinicians to request multiparametric MRI. Radiologists should be able to recognize the normal posttreatment MRI findings. Fibrosis and atrophic remnant seminal vesicles (SV) after radical prostatectomy are often found and must be differentiated from local relapse. Moreover, brachytherapy, external beam radiotherapy, and focal therapies tend to diffusely decrease the signal intensity of the peripheral zone on T2-weighted images due to the loss of water content, consequently mimicking tumor and hemorrhage. The combination of T2-weighted images and functional studies like diffusion-weighted imaging and dynamic contrast-enhanced imaging improves the identification of local relapse. Tumor recurrence tends to restrict on diffusion images and avidly enhances after contrast administration. The authors provide a review of the normal findings and the signs of local tumor relapse after radical prostatectomy, external beam radiotherapy, brachytherapy and focal therapies.

Apparent diffusion coefficient in the evaluation of side-specific extracapsular extension in prostate cancer: Development and external validation of a nomogram of clinical use.

OBJECTIVES: The aim of this study is to develop a nomogram of clinical utility based on apparent diffusion coefficient (ADC) from diffusion-weighted imaging to predict extracapsular extension (ECE), and to validate externally its clinical utility. MATERIALS AND METHODS: A total of 101 men (70 for the creation and 31 for external validation of the nomogram) underwent 1.5T multiparametric magnetic resonance imaging followed by radical prostatectomy at 2 different institutions. ADC values were assessed for normal and pathological tissue. Clinical and pathological variables were investigated by univariate and multivariate logistic regression analyses on 70 patients and logistic regression coefficients were used to develop our nomogram. Receiver operating characteristic curve analysis was performed to determine the optimal ADC cut off for ECE. The nomogram was then externally validated on 31 patients at another institution. RESULTS: At univariate analysis, the following variables were associated with ECE: pathological ADC and Gleason at biopsy (P<0.001) along with tumor volume and ECE at imaging (P = 0.003). At multivariate analysis, pathological ADC (P = 0.027), tumor volume (P = 0.011), and biopsy Gleason (P = 0.040) maintained their independent predictor status and were included in our nomogram together with normal ADC and ECE at imaging. Our nomogram showed a significant higher sensitivity (88%) than T2-weighted imaging (54%; P = 0.010). External validation resulted in an overall accuracy of 81%. CONCLUSIONS: ADC represents a potential imaging biomarker to predict side-specific ECE in patients with prostate cancer. Our nomogram could improve the current diagnostic pathway and possibly the therapeutic approach for this disease.

Oncologic results of laparoscopic renal cryoablation for clinical T1a tumors: 8 years of experience in a single institution.

OBJECTIVES: To review the oncologic outcomes of laparoscopic renal cryoablation (LRC) for small renal masses (SRMs) <4 cm. METHODS: The present study was an observational, retrospective analysis of LRC in 123 patients. The indications for LRC were solid SRMs of the kidney <4 cm in diameter diagnosed on preoperative computed tomography or magnetic resonance imaging as an enhancing mass. Follow-up was determined using magnetic resonance imaging. Local recurrence after LRC was defined as an enlarging or persistently enhancing treatment site on follow-up imaging. RESULTS: A total of 131 SRMs in 123 patients (91 men and 32 women) were treated from September 2000 to June 2008. The mean tumor size was 2.14 ± 0.86 cm (range 0.5-4). Biopsy cores from the 123 patients revealed clear cell renal cell carcinoma (RCC) in 69 patients (56.1%), papillary RCC in 8 (6.53%), chromophobe RCC in 3 (2.4%), mucinous, tubular, and spindle RCC in 1 (0.8%), oncocytoma in 27 (21.9%), angiomyolipoma in 5 (4.1%), and xanthogranulomatous pyelonephritis in 1 patient (0.8%). The biopsy findings were nondiagnostic (fibrotic/necrotic tissue) in 9 cases (7.3%). The mean follow-up was 46.04 ± 25.75 months (median 41, range 12-96). In 44 patients with RCC and a mean follow-up of 61.3 ± 13.76 months, the cancer-specific survival rate was 100% and the overall survival rate was 93.2%. None of the 53 patients (RCC plus those with nonmalignant lesions) who had follow-up >5 years developed radiographic recurrence. CONCLUSIONS: Our findings have confirmed that LRC can be considered a safe and intermediate-term effective method to treat SRMs.