Is Likert better than PI-RADS at predicting prostate cancer on MRI and can a mathematical algorithm achieve similar results?

BACKGROUND: Prostate Imaging Reporting & Data System (PI-RADS) is an internationally recognized system to quantify risk of prostate cancer on magnetic resonance imaging (MRI). However, studies have suggested methods to improve predictive accuracy. PURPOSE: To assess two different methods that aim to improve the accuracy of PI-RADS scores: a subjective Likert score given by experienced reporters, and an objective Calculated Adjustment of PI-RADS Equivocal Score (CAPES). MATERIAL AND METHODS: Five experienced reporters in a quaternary referral unit used a standardized reporting template to prospectively collect PI-RADS and Likert scores for 1467 multiparametric MRI (mpMRI) scans between January 2021 and June 2022. Histology results were recorded for patients who underwent trans-perineal biopsy. The CAPES tool was retrospectively applied to the cases scoring PI-RADS 3. A theoretical standardized biopsy protocol (assuming all patients scoring ≥3 were referred for biopsy) was used to compare the three scoring systems for sensitivity, specificity, and positive predictive value (PPV). RESULTS: Across all reporters, significantly fewer equivocal "3" scores were given using Likert (15.7%) or CAPES (2.2%) compared to PI-RADS (24.1%). Assuming a protocol where all patients scoring ≥3 were biopsied, Likert had a higher specificity (69.0% vs. 54.4%), sensitivity (98.3% vs. 97.7%), and PPV (49.9% vs. 40.3%) than PI-RADS for identifying ISUP ≥2 cancer. The CAPES tool had an even higher specificity (81.4%) and PPV (61.2%) with only a slightly lower sensitivity (93.4%) resulting in 37.1% (n = 316) fewer biopsies than PI-RADS, and 22.4% (n = 155) fewer biopsies than Likert across 1467 patients. CONCLUSIONS: Compared to PI-RADS scoring, Likert scoring or CAPES can result in fewer equivocal scores, greater PPV, and fewer unnecessary biopsies.

Does including histological outcomes in a multiparametric MRI report improve prostate biopsy decision making?

OBJECTIVES: To see if inserting audited histological outcome data for each Likert score into prostate mpMRI reports was helpful for clinicians counselling patients and influenced prostate biopsy uptake. METHODS: A single radiologist reported 791 mpMRI scans for query prostate cancer between 2017 and 2019. A structured template which included histological outcome data from this cohort was devised and included in 207 mpMRI reports between January and June 2021. The outcomes of the new cohort were compared with the historical cohort, and with 160 contemporaneous reports without histological outcome data from the four other radiologists in the department. The opinion of this template was sought from referring clinicians who counselled patients. RESULTS: The proportion of patients biopsied fell from 58.0 to 32.9% overall between the n = 791 cohort and the n = 207 cohort. This was most noticeable in those scoring Likert 3, where the proportion biopsied fell from 78.4 to 42.9%. This reduction was also seen when comparing the biopsy rates of patients scored Likert 3 by other reporters in a contemporaneous n = 160 cohort without the audit information (65.2%) with the n = 207 cohort (42.9%). 100% of counselling clinicians were in favour and 66.7% said it gave them greater confidence to advise the patient when they did not need a biopsy. CONCLUSION: Fewer low-risk patients choose unnecessary biopsies when audited histological outcomes for the radiologist's Likert scores are included in mpMRI reports. ADVANCES IN KNOWLEDGE: Clinicians welcome reporter-specific audit information in mpMRI reports which could result in fewer biopsies.

Is there a correlation between urolithiasis in horseshoe kidneys and isthmus thickness or renal angulation?

BACKGROUND: Stone disease is a common complication of horseshoe kidneys (HSK). There are currently limited studies that examine the relationship between HSK anatomy and stone formation. We aim to determine if there is such an association by measuring the isthmus size and renal angulation in both stone and non-stone forming HSK using computed tomography (CT). METHOD: This is a retrospective study performed at a single tertiary centre. Using the radiological information system, all CT reports between 01 January 2010 and 31 December 2015 were searched for the keyword 'horseshoe' on the radiological information system. This produced a list of 285 reports. Each report and image packet of these 285 studies were reviewed to confirm the presence of an HSK and duplicate patients from multiple examinations were highlighted. One hundred and thirty-eight unique HSK patients were obtained and the studies were assessed for the presence or absence of stones. A total of 112 HSK were found; 88 of which contained no stone and 24 with stone. Angle measurements and isthmus size were measured on these kidneys. As axial images are obtained as standard in all cases, these measurements were all obtained in the axial plane. All parameters were measured and recorded manually by one person so as to reduce inter-observer variability. RESULTS: Isthmus size varied widely, measuring from 2 to 39 mm. Right renal angle ranged from 51 to 158°, left 38 to 152°. CONCLUSION: The isthmus size and renal angle measurements were not found to be significant determinants for stone disease in our patient population.

Efficacy and toxicity outcomes for patients treated with focal salvage high dose rate brachytherapy for locally recurrent prostate cancer.

INTRODUCTION: Isolated local recurrence of prostate cancer following primary radiotherapy or brachytherapy may be treated with focal salvage high dose rate brachytherapy, although there remains an absence of high quality evidence to support this approach. METHODS: Men with prostate cancer treated consecutively between 2015 and 2018 using 19 Gy in a single fraction high dose rate brachytherapy (HDR) for locally recurrent prostate cancer were identified from an institutional database. Univariable analysis was performed to evaluate the relationship between patient, disease and treatment factors with biochemical progression free survival (bPFS). RESULTS: 43 patients were eligible for evaluation. Median follow up duration was 26 months (range 1-60). Median bPFS was 35 months (95% confidence interval 25.6-44.4). Kaplan-Meier estimates for bPFS at 1, 2 and 3 years post salvage were 95.2%, 70.6% and 41.8% respectively. On univariable Cox regression analysis, only nadir PSA was significantly associated with bPFS although the majority of patients were also treated with androgen deprivation therapy. Only one late grade 3 genitourinary toxicity was observed. CONCLUSION: Focal salvage HDR brachytherapy may provide good biochemical control with a low risk of severe toxicity. Further evaluation within clinical trials are needed to establish its role in the management of locally recurrent prostate cancer.

Antegrade removal of a knotted ureteric stent: Case report and review of literature.

Ureteral stents are routinely used in urological practice for many indications including obstruction of ureter, ureteral stricture, prior to treatment with extracorporeal shock wave lithotripsy, and to promote healing following ureteral injury. Complications reported with ureteric stents include stent migration, stent rupture, encrustation, ureteral perforation, erosion, and fistulation. Knotting of an indwelling ureteral stent is a very rare complication, with fewer than 30 cases reported in the literature. Techniques for managing this complication include using a holmium laser to cut the knot, percutaneous antegrade removal, and gentle traction. We describe the case of a knotted stent and its removal along with a comprehensive literature review.

A comparison of outcomes for patients with intermediate and high risk prostate cancer treated with low dose rate and high dose rate brachytherapy in combination with external beam radiotherapy.

INTRODUCTION: There is evidence to support use of external beam radiotherapy (EBRT) in combination with both low dose rate brachytherapy (LDR-EBRT) and high dose rate brachytherapy (HDR-EBRT) to treat intermediate and high risk prostate cancer. METHODS: Men with intermediate and high risk prostate cancer treated using LDR-EBRT (treated between 1996 and 2007) and HDR-EBRT (treated between 2007 and 2012) were identified from an institutional database. Multivariable analysis was performed to evaluate the relationship between patient, disease and treatment factors with biochemical progression free survival (bPFS). RESULTS: 116 men were treated with LDR-EBRT and 171 were treated with HDR-EBRT. At 5 years, bPFS was estimated to be 90.5% for the LDR-EBRT cohort and 77.6% for the HDR-EBRT cohort. On multivariable analysis, patients treated with HDR-EBRT were more than twice as likely to experience biochemical progression compared with LDR-EBRT (HR 2.33, 95% CI 1.12-4.07). Patients with Gleason ≥8 disease were more than five times more likely to experience biochemical progression compared with Gleason 6 disease (HR 5.47, 95% CI 1.26-23.64). Cumulative incidence of ≥grade 3 genitourinary and gastrointestinal toxicities for the LDR-EBRT and HDR-EBRT cohorts were 8% versus 4% and 5% versus 1% respectively, although these differences did not reach statistical significance. CONCLUSION: LDR-EBRT may provide more effective PSA control at 5 years compared with HDR-EBRT. Direct comparison of these treatments through randomised trials are recommended to investigate this hypothesis further.

Importance of dynamic contrast enhanced magnetic resonance imaging for targeting biopsy and salvage treatments after prostate cancer recurrence.

PURPOSE: Evaluate T2 weighted MRI (T2W), diffusion weighted imaging (DWI), and dynamic contrast enhanced MRI (DCE-MRI) for determining areas of prostate cancer recurrence to target biopsy or salvage treatment in patients previously treated with I-125 seed brachytherapy. MATERIAL AND METHODS: MRI data from 15 patients, whose primary treatment was I-125 seed brachytherapy and who were subsequently treated with partial gland salvage high-dose-rate brachytherapy were retrospectively analyzed. Two radiologists independently reviewed imaging on two occasions blinded to clinical and biopsy information. At first review, the T2W and DWI sequences were assessed for likely presence of tumor and at second review, the additional DCE-MRI sequence was assessed. Results were recorded and compared on a prostate diagram divided into 12 sectors (quadrants at each of base, mid-gland, and apex) plus seminal vesicles (SV). RESULTS: Number of patients for whom recurrence was visible was 7/15 for T2W, 6.5/15 for DWI, and 15/15 for DCE-MRI (average of results for the two radiologists). Approximately, half of the sectors identified as showing recurrence were at the anterior base of the prostate. CONCLUSIONS: In prostate cancer patients previously treated with I-125 permanent seed implants, DCE-MRI is superior to T2W and DWI in defining areas of recurrence, and should be used to target biopsy and for treatment planning of focal salvage therapies.

Cumulative radiation dose due to diagnostic investigations in seriously injured trauma patients admitted to critical care.

A retrospective review of case notes and radiology records was performed in order to estimate the amount and sources of ionising radiation multiply injured trauma patients are exposed to, during their initial investigations and subsequent critical care admission. Data were available for 431 radiological investigations from 36 patients. Results showed initial emergency department imaging (combined computed tomography (CT) and plain radiographs) contributed 70% of the total radiation dose. Overall, CT scans were responsible for 80% and plain radiographs 15% of the total radiation dose. Plain radiographs performed after the initial resuscitation period contributed the greatest number of investigations but accounted for only 8% of total radiation exposure. Median cumulative effective dose was estimated to be between 16 and 29 millisieverts, resulting in an estimated increased life time risk of carcinogenesis of between 1 in 614 and 1 in 1075 above baseline.