A novel model of artificial intelligence based automated image analysis of CT urography to identify bladder cancer in patients investigated for macroscopic hematuria.

OBJECTIVE: To evaluate whether artificial intelligence (AI) based automatic image analysis utilising convolutional neural networks (CNNs) can be used to evaluate computed tomography urography (CTU) for the presence of urinary bladder cancer (UBC) in patients with macroscopic hematuria. METHODS: Our study included patients who had undergone evaluation for macroscopic hematuria. A CNN-based AI model was trained and validated on the CTUs included in the study on a dedicated research platform (Recomia.org). Sensitivity and specificity were calculated to assess the performance of the AI model. Cystoscopy findings were used as the reference method. RESULTS: The training cohort comprised a total of 530 patients. Following the optimisation process, we developed the last version of our AI model. Subsequently, we utilised the model in the validation cohort which included an additional 400 patients (including 239 patients with UBC). The AI model had a sensitivity of 0.83 (95% confidence intervals [CI], 0.76-0.89), specificity of 0.76 (95% CI 0.67-0.84), and a negative predictive value (NPV) of 0.97 (95% CI 0.95-0.98). The majority of tumours in the false negative group (n = 24) were solitary (67%) and smaller than 1 cm (50%), with the majority of patients having cTaG1-2 (71%). CONCLUSIONS: We developed and tested an AI model for automatic image analysis of CTUs to detect UBC in patients with macroscopic hematuria. This model showed promising results with a high detection rate and excessive NPV. Further developments could lead to a decreased need for invasive investigations and prioritising patients with serious tumours.

Shortened time to diagnosis for patients suspected of urinary bladder cancer managed in a standardized care pathway was associated with an improvement in tumour characteristics.

Objectives: To evaluate whether the implementation of standardized care pathway (SCP) for patients with suspected urinary bladder cancer (UBC) was associated with changes in tumour characteristics. Additionally, the study aims to explore whether there was a shift in the selection of patients prioritized for immediate evaluation regarding suspicion of UBC. Materials and Methods: The study included all patients diagnosed with UBC in the NU Hospital Group between 2010 and 2019. To evaluate changes associated with SCP, patients were divided into two diagnostic time periods, either before (2010-2015) or during (2016-2019) the implementation of the SCP. To evaluate which patients were prioritized for prompt evaluation within 13 days, logistic regression analysis was performed on all patients before and during SCP. Results: Median time to transurethral resection of the tumour in urinary bladder (TURBT) decreased from 29 days (interquartile range [IQR] 16-48) before SCP to 12 days (IQR 8-19) during SCP (p < 0.001) with a clear break from 2016. The proportion of cT2 + tumours decreased during SCP from 26% to 20% (p = 0.035). In addition, tumours detected during SCP were smaller (p = 0.023), but with more multiple lesions (p = 0.055) and G3 tumours (p = 0.007). During SCP, there was no statistically significant difference between the groups of patients with TURBT within or after 13 days. In contrast, before SCP, a majority of the patients treated within 13 days had advanced tumours and were admitted from the emergency ward. Conclusions: The implementation of an SCP for suspected UBC was associated with improved tumour characteristics. Interestingly, during SCP, there were no substantial differences in patients' or tumours' characteristics among those who underwent TURBT within or after 13 days. This indicates that the 13-day timeframe for TURBT might be prolonged, especially in less urgent cases in order to facilitate a prioritization of more severe cases with treatable disease.

Diagnostic value of repeated comprehensive investigation with CT urography and cystoscopy for recurrent macroscopic haematuria.

Objectives: To perform a descriptive analysis of a series of patients with recurrent macroscopic haematuria after a primary standard evaluation including computed tomography urography (CTU) and cystoscopy negative for urinary bladder cancer (UBC) and upper tract urothelial cancer (UTUC) and to identify potential factors associated with occurrence of recurrent macroscopic haematuria. Methods: All patients older than 50 years who underwent urological investigation for macroscopic haematuria with both cystoscopy and CTU 2015-2017 were retrospectively reviewed. A descriptive analysis of the primary and later investigations for recurrent macroscopic haematuria was performed. To investigate the association between explanatory variables and the occurrence of recurrent macroscopic haematuria, a Poisson regression analysis was performed. Results: A total of 1395 eligible individuals with primary standard investigation negative for UBC and UTUC were included. During a median follow-up of 6.2 (IQR 5.3-7) years, 248 (18%) patients had recurrent macroscopic haematuria, of whom six patients were diagnosed with UBC, two with prostate cancer, one with renal cell carcinoma and one had a suspected UTUC at the repeated investigation. Within 3 years, 148 patients (11%) experienced recurrent macroscopic haematuria, of whom two patients were diagnosed with low-grade UBC (TaG1-2), one with T2G3 UBC and one with low-risk prostate cancer. The presence of an indwelling catheter, use of antithrombotic medication, pathological findings at CTU or cystoscopy or history of pelvic radiotherapy were all statistically significant independent predictors for increased risk for recurrent macroscopic haematuria. Conclusion: In the case of recurrent macroscopic haematuria within 3 years of primary standard evaluation for urinary tract cancer, there was a low risk of later urological malignancies in patients initially negative for UBC and UTUC. Therefore, waiting 3 years before conducting another complete investigation in cases of recurrent macroscopic haematuria might be appropriate.

Computed tomography urography with corticomedullary phase can exclude urinary bladder cancer with high accuracy.

BACKGROUND: To evaluate the diagnostic accuracy of computed tomography-urography (CTU) to rule out urinary bladder cancer (UBC) and whether patients thereby could omit cystoscopy. METHODS: All patients evaluated for macroscopic hematuria with CTU with cortico-medullary phase (CMP) and cystoscopy at our institute between 1st November 2016 and 31st December 2019 were included. From this study cohort a study group consisting of all UBC patients and a control group of 113 patients randomly selected from all patients in the study cohort without UBC. Two radiologists blinded to all clinical data reviewed the CTUs independently. CTUs were categorized as positive, negative or indeterminate. Diagnostic accuracy and proportion of potential omittable cystoscopies were calculated for the study cohort by generalizing the results from the study group. RESULTS: The study cohort consisted of 2195 patients, 297 of which were in the study group (UBC group, n = 207 and control group, n = 90). Inter-rater reliability was high (κ 0.84). Evaluation of CTUs showed that 174 patients were assesessed as positive (showing UBC), 46 patients as indeterminate (not showing UBC but with limited quality of CTU), and 77 patients as negative (not showing UBC with good quality of CTU). False negative rate was 0.07 (95%, CI 0.04-0.12), false positive rate was 0.01 (95% CI 0.0-0.07) and negative predictive value was 0.99 (95% CI 0.92-1.0). The area under the curve was 0.93 (95% CI 0.90-0.96). Only 2.9% (3/102) with high-risk tumors and 11% (12/105) with low- or intermediate-risk tumors had a false negative CTU. Cystoscopy could potentially have been omitted in 57% (1260/2195) of all evaluations. CONCLUSIONS: CTU with CMP can exclude UBC with high accuracy. In case of negative CTU, it might be reasonable to omit cystoscopy, but future confirmative studies with possibly refined technique are needed.

Standardized care pathways for patients with suspected urinary bladder cancer: the Swedish experience.

OBJECTIVES: To compare time intervals to diagnosis and treatment, tumor characteristics, and management in patients with primary urinary bladder cancer, diagnosed before and after the implementation of a standardized care pathway (SCP) in Sweden. MATERIALS AND METHODS: Data from the Swedish National Register of Urinary Bladder Cancer was studied before (2011-2015) and after (2016-2019) SCP. Data about time from referral to transurethral resection of bladder tumor (TURBT), patients and tumor characteristics, and management were analyzed. Subgroup analyses were performed for cT1 and cT2-4 tumors. RESULTS: Out of 26,795 patients, median time to TURBT decreased from 37 to 27 days after the implementation of SCP. While the proportion of cT2-T4 tumors decreased slightly (22-21%, p < 0.001), this change was not stable over time and the proportions cN + and cM1 remained unchanged. In the subgroups with cT1 and cT2-4 tumors, the median time to TURBT decreased and the proportions of patients discussed at a multidisciplinary team conference (MDTC) increased after SCP. In neither of these subgroups was a change in the proportions of cN + and cM1 observed, while treatment according to guidelines increased after SCP in the cT1 group. CONCLUSION: After the implementation of SCP, time from referral to TURBT decreased and the proportion of patients discussed at MDTC increased, although not at the levels recommended by guidelines. Thus, our findings point to the need for measures to increase adherence to SCP recommendations and to guidelines.

A rare case of a necrotized urethral prolapse in a postmenopausal woman with acute urinary retention.

CASE: Urethral prolapse (UP) is a rare condition with unknown etiology. We reported on an 86-year-old woman with a normal BMI and cystocele, presented with acute urinary retention and perineal pain. A residual urine of 950 mL was measured and released by an indwelling catheter. The physical examination revealed 2 × 3 cm severely sore and purple polyp around the urethral meatus with signs of necrosis. A diagnosis of a strangulated urethral prolapse was stated. OUTCOME: The patient was admitted to the Department of Urology, and treated with surgical excision using the four-quadrant excisional technique. The histopathological examination revealed a non-keratinized, inflammatory squamous epithelium. At a follow-up visit, the patient remained asymptomatic and a complete anatomical resolution was achieved. CONCLUSION: UP is an uncommon, sometimes misdiagnosed condition. The management is controversial and to date no consensus exists. This clinical picture is sufficient for diagnosis and surgical excision of the prolapsed urethral mucosa is reasonable if there are signs of strangulation.