P-score in preoperative biopsies accurately predicts P-score in final pathology at radical prostatectomy in patients with localized prostate cancer.

BACKGROUND: Prostate cancer (PCa) is a highly heterogeneous, multifocal disease, and identification of clinically significant lesions is challenging, which complicates the choice of adequate treatment. The Prostatype® score (P-score) is intended to guide treatment decisions for newly diagnosed PCa patients based on a three-gene signature (IGFBP3, F3, and VGLL3) and clinicopathological information obtained at diagnosis. This study evaluated association of the P-score measured in preoperative magnetic resonance imaging/transrectal ultrasound fusion-guided core needle biopsies (CNBs) and the P-score measured in radical prostatectomy (RP) specimens of PCa patients. We also evaluated the P-score association with the pathology of RP specimens. Furthermore, concordance of the P-score in paired CNB and RP specimens, as well as in index versus concomitant nonindex tumor foci from the same RP was investigated. METHODS: The study included 100 patients with localized PCa. All patients were diagnosed by CNB and underwent RP between 2015 and 2018. Gene expression was assessed with the Prostatype® real-time quantitative polymerase chain reaction kit and the P-score was calculated. Patients were categorized into three P-score risk groups according to previously defined cutoffs. RESULTS: For 71 patients, sufficient CNB tumor material was available for comparison with the RP specimens. The CNB-based P-score was associated with the pathological T-stage in RP specimens (p = 0.02). Moreover, the CNB-based P-score groups were in substantial agreement with the RP-based P-score groups (weighted κ score: 0.76 [95% confidence interval, 95% CI: 0.60-0.92]; Spearman's rank correlation coefficient r = 0.83 [95% CI: 0.74-0.89]; p < 0.0001). Similarly, the P-score groups based on paired index tumor and concomitant nonindex tumor foci (n = 64) were also in substantial agreement (weighted κ score: 0.74 [95% CI: 0.57-0.91]; r = 0.83 [95% CI: 0.73-0.89], p < 0.0001). CONCLUSIONS: Our findings suggest that the P-score based on preoperative CNB accurately reflects the pathology of the whole tumor, highlighting its value as a decision support tool for newly diagnosed PCa patients.

Bi-parametric MRI/TRUS fusion targeted repeat biopsy after systematic 10-12 core TRUS-guided biopsy reveals more significant prostate cancer especially in anteriorly located tumors.

Background: MRI and fusion guided biopsy have an increased role in the diagnosis of prostate cancer. Purpose: To demonstrate the possible advantages with Bi-parametric MRI fusion-guided repeat biopsy over systematic 10-12-core biopsy for the diagnosis of prostate cancer. Material and Methods: Four hundred and twenty-three consecutive men, with previous systematic 10-12-core TRUS-guided biopsy, and with suspicion of, or diagnosis of, low-risk prostate cancer underwent fusion-guided prostate biopsy between February 2015 and February 2017. The material was retrospectively assessed. In 220 cases no previous cancer was diagnosed, and in 203 cases confirmatory fusion guided biopsy was performed prior to active monitoring. MRI was classified according to PI-RADS. Systematic biopsy was compared to fusion guided biopsy for the detection of cancer, and PI-RADS was compared to the Gleason score. Results: Fusion guided biopsy detected significantly more cancers than systematic (p < .001). Gleason scores were higher in the fusion biopsy group (p < .001). Anterior tumors were present in 54% of patients. Fusion biopsy from these lesions showed cancer in 53% with previously negative biopsy in systematic biopsies and 66% of them were upgraded from low risk to intermediate or high-risk cancers. Conclusion: These results show superior detection rate and grading of bi-parametric MRI/TRUS fusion targeted repeat biopsy over systematic 10-12 core biopsies. Fusion guided biopsy detects more significant cancers despite using fewer cores. The risk group was changed for many patients initially selected for active surveillance due to upgrading of tumors. Bi-parametric MRI shows promising results in detecting anterior tumors in patients with suspected prostate cancer.

Accuracy of iodine quantification using dual-energy computed tomography with focus on low concentrations.

BACKGROUND: Iodine quantification using dual-energy computed tomography (DECT) is helpful in characterizing, and follow-up after treatment of tumors. Some malignant masses, for instance papillary renal cell carcinomas (p-RCC), are hard to differentiate from benign lesions because of very low contrast enhancement. In these cases, iodine concentrations might be very low, and it is therefore important that iodine quantification is reliable even at low concentrations if this technique is used. PURPOSE: To examine the accuracy of iodine quantification and to determine whether it is also accurate for low iodine concentrations. MATERIAL AND METHODS: Twenty-six syringes with different iodine concentrations (0-30 mg I/mL) were scanned in a phantom model using a DECT scanner with two different kilovoltage and image reconstruction settings. Iodine concentrations were measured and compared to known concentration. Absolute and relative errors were calculated. RESULTS: For concentrations of 1 mg I/mL or higher, there was an excellent correlation between true and measured iodine concentrations for all settings (R = 0.999-1.000; P < 0.001). For concentrations <1.0 mg I/mL, the relative error was greater. Absolute and relative errors were smaller using tube voltages of 80/Sn140 kV than 100/Sn140 kV (P < 0.01). Reconstructions using a 3.0-mm slice thickness had less variance between repeated acquisitions versus 0.6 mm (P < 0.001). CONCLUSION: Iodine quantification using DECT was in general very accurate, but for concentrations < 1.0 mg I/mL the technique was less reliable. Using a tube voltage with larger spectral separation was more accurate and the result was more reproducible using thicker image reconstructions.

Split renal function after treatment of small renal masses: comparison between radiofrequency ablation and laparoscopic partial nephrectomy.

BACKGROUND: Radiofrequency ablation (RFA) and laparoscopic partial nephrectomy (LPN) are used to treat small renal masses (SRM; ≤4 cm), although there are conflicting results in the changes in creatinine and estimated glomerular filtration rate (eGFR) after treatment. On contrast-enhanced computed tomography (CE-CT) images, the quantity and quality of renal function can be evaluated by calculating the split renal function (SRF). PURPOSE: To compare renal function after RFA or LPN treatment of SRMs through evaluation of the SRF in the affected kidney. MATERIAL AND METHODS: Single T1a renal tumors successfully treated with RFA (n = 60) or LPN (n = 31) were retrospectively compared. The SRF was calculated on pre-treatment CE-CT images and the first follow-up exam after completed treatment. Serum creatinine and eGFR values were collected simultaneously. To compare renal function outcomes, Student's t-test and multivariable linear regression models (adjusted to RFA/LPN treatment, pre-treatment SRF/eGFR, BMI, age, tumor characteristics, and Charlson Comorbidity Index) were used. RESULTS: SRF was reduced in both groups, although reduction was greater in the LPN group (LPN -5.7%) than in the RFA group (RFA -3.5%; P = 0.013). After adjusted analysis, the LPN group still had greater SRF reduction (difference 3.2%, 95% confidence interval 1.3-1.5; P = 0.001). There was no difference between groups in the change of creatinine/eGFR after treatment. CONCLUSION: Both RFA and LPN are nephron-sparing when treating SRMs. However, in this series, reduction of SRF in the affected kidney was smaller after RFA, having a more favorable preservation of renal function than LPN.

Microwave ablation of 105 T1 renal tumors: technique efficacy with a mean follow-up of two years.

BACKGROUND: Thermal ablation (TA) with radiofrequency (RFA) or cryoablation (CA) are established treatments for small renal masses (≤4 cm). Microwave ablation (MWA) has several potential benefits (decreased ablation time, less susceptibility to heat-sink, higher lesion temperatures than RFA) but is still considered experimental considering the available small-sample studies with short follow-up. PURPOSE: To evaluate technique efficacy and complications of our initial experience of renal tumors treated using percutaneous MWA with a curative intent. MATERIAL AND METHODS: A total of 105 renal tumors (in 93 patients) were treated between April 2014 and August 2017. MWA was performed percutaneously with computed tomography (CT) guidance under conscious sedation (n=82) or full anesthesia. Patients were followed with contrast-enhanced CT scans at six months and yearly thereafter for a minimum of five years. The mean follow-up time was 2.1 years. The percentage of tumors completely ablated in a single session (primary efficacy rate) and those successfully treated after repeat ablation (secondary efficacy rate) were recorded. Patient and tumor characteristics as well as complications were collected retrospectively. RESULTS: The median patient age was 70 years and median tumor size was 25 mm. Primary efficacy rate was 96.2% (101/105 tumors). After including two residual tumors for a second ablation session, secondary efficacy was 97.1% (102/105). Periprocedural complications were found in 5.2% (5/95) sessions: four Clavien-Dindo I and one Clavien-Dindo IIIa. One postprocedural Clavien-Dindo II complication was found. CONCLUSION: MWA has high efficacy rates and few complications compared to other TA methods at a mean follow-up of two years.

Analgesic effects of dexmedetomidine and remifentanil on periprocedural pain during percutaneous ablation of renal carcinoma.

Background: Percutaneous ablation of renal carcinoma is frequently a favourable treatment alternative, especially in elderly patients suffering from co-morbidities. Also, it is less resource-demanding than conventional surgery of renal carcinoma, and one may, therefore, assume that the incidence of this procedure may increase. Analgesia is necessary during this intervention. The aim of this study was to explore the possibility of analgosedation and its relation to patient comfort and safety during percutaneous ablation of renal carcinoma.Methods: Forty-six patients, sedated with dexmedetomidine and remifentanil, supplemented with infiltration anaesthesia (lidocaine 1%), underwent percutaneous (radiofrequency or microwave) ablation of renal carcinoma in this prospective study.Results: The patients expected pain intensity around the numerical rating score (NRS) 4.5 (interquartile range [IQR] 3.5-5.5), which was slightly lower than pain experienced during the procedure NRS 5 (IQR 2-7; p = 0.49). Eight percent of the patients needed supplementary morphine during the ablation procedure. Sedation score did not differ during ablation, at arrival to or discharge from the recovery ward. Median periprocedural treatment time was 12 minutes (IQR 12-16). Treatment time did not correlate with experienced pain (R2=0.000074, p = 0.96). The median length of stay in the recovery room was 120 minutes (IQR 84-154). There were seven serious adverse events.Conclusions: This proof-of-concept study has shown that analgosedation during percutaneous ablation of renal carcinoma can be performed with a generally tolerable degree of patient satisfaction. However, pain occurs and should be managed adequately. Patient safety must be a major concern for the anaesthetic care.

Predictive value of secondary signs of obstruction in follow-up computed tomography of ureteral stones: a study with dynamic computed tomography.

OBJECTIVES: This study aimed to determine the ratio of obstruction and predictive values of secondary signs in follow-up computed tomography (CT) of ureterolithiasis patients; to correlate stone characteristics with obstruction; to compare enhancement of obstructed and non-obstructed kidneys; and to compare radiation dose of the dynamic CT protocol to an excretory-phase protocol. MATERIALS AND METHODS: This retrospective study assessed 49 follow-up CT scans of patients with remaining ureterolithiasis after a renal colic episode. Obstruction was measured as time taken to excretion of contrast medium in dynamic CT. Degree of secondary signs of obstruction was evaluated from the unenhanced CT. Data were collected on patients' gender and age, stone size and location, time from renal colic to follow-up, attenuation of the renal cortex and radiation dose. RESULTS: Obstruction was present in 28% (n = 14) at follow-up. Predictive values (sensitivity, specificity, positive predictive value, negative predictive value) were calculated for hydronephrosis (1.0, 0.63, 0.52, 1.0), hydroureter (1.0, 0.4, 0.4, 1.0), perirenal stranding (0.21, 0.94, 0.6, 0.75), Gerota's fascia (0.21, 0.97, 0.75, 0.76) and renal swelling (0.21, 0.97, 0.75, 0.76). Obstruction was not correlated with stone characteristics. Enhancement was lower in obstructed kidneys (p < 0.01). Radiation dose was reduced by 43% (1.8 mSv). CONCLUSIONS: Obstruction was found in 28% of patients. Secondary signs were scarce and of indeterminate value to the diagnosis of obstruction. The absence of hydronephrosis and hydroureter contradicted obstruction. Stone characteristics were not correlated with obstruction. Enhancement of the renal cortex was lower in obstructed kidneys. The dynamic protocol reduced the radiation dose.

Predictive factors for complete renal tumor ablation using RFA.

BACKGROUND: Radiofrequency ablation (RFA) can be used to treat renal masses in patients where surgery is preferably avoided. As tumor size and location can affect ablation results, procedural planning needs to identify these factors to limit treatment to a single session and increase ablation success. PURPOSE: To identify factors that may affect the primary efficacy of complete renal tumor ablation with radiofrequency after a single session. MATERIAL AND METHODS: Percutaneous RFA (using an impedance based system) was performed using computed tomography (CT) guidance. Fifty-two renal tumors (in 44 patients) were retrospectively studied (median follow-up, 7 months). Data collection included patient demographics, tumor data (modified Renal Nephrometry Score, histopathological diagnosis), RFA treatment data (electrode placement), and follow-up results (tumor relapse). Data were analyzed through generalized estimating equations. RESULTS: Primary efficacy rate was 83%. Predictors for complete ablation were optimal electrode placement (P = 0.002, OR = 16.67) and increasing distance to the collecting system (P = 0.02, OR = 1.18). Tumor size was not a predictor for complete ablation (median size, 24 mm; P = 0.069, OR = 0.47), but all tumors ≤2 cm were completely ablated. All papillary tumors and oncocytomas were completely ablated in a single session; the most common incompletely ablated tumor type was clear cell carcinoma (6 of 9). CONCLUSION: Optimal electrode placement and a long distance from the collecting system are associated with an increased primary efficacy of renal tumor RFA. These variables need to be considered to increase primary ablation success. Further studies are needed to evaluate the effect of RFA on histopathologically different renal tumors.

Comparison of post contrast CT urography phases in bladder cancer detection.

OBJECTIVES: The aim of this study was to investigate which post-contrast phase(s) in a four-phase CT urography protocol is (are) most suitable for bladder cancer detection. METHODS: The medical records of 106 patients with visible haematuria who underwent a CT urography examination, including unenhanced, enhancement-triggered corticomedullary (CMP), nephrographic (NP) and excretory (EP) phases, were reviewed. The post-contrast phases (n = 318 different phases) were randomized into an evaluation order and blindly reviewed by two uroradiologists. RESULTS: Twenty-one patients were diagnosed with bladder cancer. Sensitivity for bladder cancer detection was 0.95 in CMP, 0.83 in NP and 0.81 in EP. Negative predictive value (NPV) was 0.99 in CMP, 0.96 in NP and 0.95 in EP. The sensitivity was higher in CMP than in both NP (p-value 0.016) and EP (p-value 0.0003). NPV was higher in CMP than in NP (p-value 0.024) and EP (p-value 0.002). CONCLUSIONS: In the CT urography protocol with enhancement-triggered scan, sensitivity and NPV were highest in the corticomedullary phase, and this phase should be used for bladder assessment. KEY POINTS: • More bladder tumours are detected during the corticomedullary phase than during other phases. • Sensitivity and NPV for bladder cancer detection were highest in corticomedullary phase. • The corticomedullary phase in CT urography should be used for bladder assessment.

Bladder cancer detection in patients with gross haematuria: Computed tomography urography with enhancement-triggered scan versus flexible cystoscopy.

OBJECTIVE: Computed tomography urography (CTU) can be used to direct further investigation of patients if the bladder tumour detection rate is high. The aim of this study was to compare a CTU protocol including an enhancement-triggered scan and flexible cystoscopy for detecting bladder tumours. MATERIALS AND METHODS: Patients with gross haematuria undergoing CTU during 2005-2008 were included. For patients younger than 50 years the CTU protocol included unenhanced, enhancement-triggered corticomedullary, and excretory phases. Patients older than 50 years followed the same protocol plus a nephrographic phase. The entire urinary tract was examined in all phases. RESULTS: Of 435 patients, 55 patients were diagnosed with bladder tumour. CTU detected bladder tumour in 48 patients (87%). Five CTU examination reports were false positive. With CTU, sensitivity for finding bladder tumour was 0.87, specificity 0.99, positive predictive value (PPV) 0.91 and negative predictive value (NPV) 0.98. Cystoscopy detected bladder tumour in 48 patients (87%) and had one false-positive finding, resulting in sensitivity of 0.87, specificity 1.0, PPV 0.98 and NPV 0.98. CONCLUSIONS: The detection rate of bladder tumours for the CTU protocol including an enhancement-triggered scan was high and comparable to flexible cystoscopy. Hence, this protocol could be used to assess the bladder as the primary investigation and direct further investigation of the patient.

Contrast enhancement in bladder tumors examined with CT urography using traditional scan phases.

BACKGROUND: Bladder assessment in an early contrast-enhancing computed tomography urography (CTU) phase requires that bladder tumors be enhanced using contrast material. PURPOSE: To investigate the enhancement pattern in bladder tumors using a CTU protocol where the scan is enhancement triggered. MATERIAL AND METHODS: Fifty patients diagnosed with bladder cancer were examined during the unenhanced (UP), corticomedullary (CMP), and excretory phases (EP). Twenty-one patients, all aged 50 years or older, were also examined during the nephrographic phase (NP). A ROI placed in the aorta was used to start the scan during the CMP when the attenuation reached 200 Hounsfield units (HU). The NP and EP were started with a 40 s and 300 s delay, respectively, after the CMP was finished. Attenuation and size measurements were made in the axial plane. RESULTS: Mean contrast enhancement of bladder tumors was 37, 25, and 17 HU in the CMP, NP, and EP, respectively. The differences in contrast enhancement were significant across all three phases. Eighty-eight percent of patients showed the highest contrast enhancement in the CMP. In 96% of the cases, contrast enhancement >20 HU was seen. The mean value of the shortest dimension of the bladder tumors was 22 ± 12 mm. CONCLUSION: The contrast enhancement is significantly higher in the CMP than in the NP and EP, suggesting that the CMP is preferable when assessing the bladder in the early contrast enhancing phase.

How much dose can be saved in three-phase CT urography? A combination of normal-dose corticomedullary phase with low-dose unenhanced and excretory phases.

OBJECTIVE: The purpose of this study was to investigate the degree to which the total radiation dose for CT urography can be lowered by selective reduction of the dose in the unenhanced and excretory phases when images in these phases are systematically evaluated alongside normal-dose corticomedullary phase images. SUBJECTS AND METHODS: Twenty-seven patients (mean age, 74±9 years) underwent single-bolus CT urography with acquisition in the unenhanced, corticomedullary, and 5-minute excretory phases. The scanning parameters for normal-dose CT urography were as follows: 16×0.75 mm, 120 kV, and automatic exposure control technique reference tube loads of 100, 120, and 100 effective mAs (mAseff). The patients also underwent low-dose unenhanced and excretory phase scanning, in which the dose was escalated stepwise from a volume CT dose index (CTDIvol) of 1.7 to 6.6 mGy (reference 20-40-60-80 mAseff). Images were analyzed for quality and diagnostic confidence. If low-dose scans of three patients were inadequate, the study continued to the next dose level. When 20 patients were successfully included in the unenhanced and excretory phase groups, the study ended. Doses were calculated with a CT patient dosimetry calculator. RESULTS: Combined with the normal dose for corticomedullary phase scanning, doses of CTDIvol 1.5 mGy for the unenhanced phase and CTDIvol 2.7 mGy for the excretory phase were sufficient. The effective dose for three-phase CT urography was lowered from 16.2 to 9.4 mSv, a decrease of 42%. Diagnostic confidence in low-dose images was equal to that in normal-dose images when low-dose unenhanced and excretory phase images were read along-side normal-dose corticomedullary phase images. CONCLUSION: With a three-phase CT urographic protocol, significant dose reductions in the unenhanced and excretory phases can be achieved when these phases are combined with a normal-dose corticomedullary phase.

CT of the kidneys: what size are renal cell carcinomas when they cause symptoms or signs?

OBJECTIVE: To investigate the size of renal cell carcinomas (RCCs) when they cause macroscopic hematuria or other symptoms and/or signs. MATERIAL AND METHODS: A retrospective review of 232 patients (136 males, 96 females; mean age 68 +/- 11 years; age range 40-90 years) with a diagnosis of RCC was undertaken. Patients were grouped according to the presenting symptoms and/or signs caused by the RCCs. Tumor size was measured on CT images. RESULTS: Of the RCCs, 29% were found incidentally and 71% caused symptoms and/or signs. The incidentally found RCCs measured 4.9 +/- 2.6 cm (range 2-12 cm) and RCCs causing symptoms and signs measured 8.9 +/- 3.2 cm (range 3-18 cm); this size difference was significant (p < 0.001). None of the RCCs causing macroscopic hematuria were <4 cm in size and only 3/165 (2%) of the symptomatic RCCs were <4 cm in size. DISCUSSION: If small (<4 cm) RCCs do not cause symptoms, patients with them will not be referred for CT or any other imaging modality. Therefore, if a 2-cm RCC is found in a patient presenting with macroscopic hematuria, it is unlikely that this small RCC caused the hematuria and another cause of the hematuria must be ruled out.