Long-term outcomes and cost savings of office fulguration of papillary Ta low-grade bladder cancer.

OBJECTIVES: To assess whether office-based fulguration (OF) under local anaesthesia for small, recurrent, pathological Ta low-grade (LG) non-muscle-invasive bladder cancer (NMIBC) is an effective alternative to transurethral resection of bladder tumour (TURBT), avoiding the costs and risks of procedure, and anesthesia. PATIENTS AND METHODS: Of 521 patients with primary TaLG NMIBC, this retrospective study included 270 patients who underwent OF during follow-up for recurrent, small, papillary LG-appearing tumours at a university centre (University Health Network, University of Toronto, Canada). We assessed the cumulative incidence of cancer-specific mortality (CSM) and disease progression (to MIBC or metastases), as well as possible direct cost savings. RESULTS: In the 270 patients with recurrent TaLG NMIBC treated with OF, the mean (sd) age was 64.9 (13.3) years, 70.8% were men, and 60.3% had single tumours. The mean (sd, range) number of OF procedures per patient was 3.1 (3.2, 1-22). The median (interquartile range) follow-up was 10.1 (5.8-16.2) years. Patients also underwent a mean (sd) of 3.6 (3.0) TURBTs during follow-up in case of numerous or bulkier recurrence. In all, 44.4% of patients never received intravesical therapy. The 10-year incidence of CSM and progression were 0% and 3.1% (95% confidence interval 0.8-5.4%), respectively. Direct cost savings in Ontario were estimated at $6994.14 (Canadian dollars) per patient over the study follow-up. CONCLUSIONS: This study supports that properly selected patients with recurrent, apparent TaLG NMIBC can be safely managed with OF under local anaesthesia with occasional TURBT for larger or numerous recurrent tumours, without compromising long-term oncological outcomes. This approach could generate substantial cost-saving to healthcare systems, is patient-friendly, and could be adopted more widely.

Development, multi-institutional external validation, and algorithmic audit of an artificial intelligence-based Side-specific Extra-Prostatic Extension Risk Assessment tool (SEPERA) for patients undergoing radical prostatectomy: a retrospective cohort study.

BACKGROUND: Accurate prediction of side-specific extraprostatic extension (ssEPE) is essential for performing nerve-sparing surgery to mitigate treatment-related side-effects such as impotence and incontinence in patients with localised prostate cancer. Artificial intelligence (AI) might provide robust and personalised ssEPE predictions to better inform nerve-sparing strategy during radical prostatectomy. We aimed to develop, externally validate, and perform an algorithmic audit of an AI-based Side-specific Extra-Prostatic Extension Risk Assessment tool (SEPERA). METHODS: Each prostatic lobe was treated as an individual case such that each patient contributed two cases to the overall cohort. SEPERA was trained on 1022 cases from a community hospital network (Trillium Health Partners; Mississauga, ON, Canada) between 2010 and 2020. Subsequently, SEPERA was externally validated on 3914 cases across three academic centres: Princess Margaret Cancer Centre (Toronto, ON, Canada) from 2008 to 2020; L'Institut Mutualiste Montsouris (Paris, France) from 2010 to 2020; and Jules Bordet Institute (Brussels, Belgium) from 2015 to 2020. Model performance was characterised by area under the receiver operating characteristic curve (AUROC), area under the precision recall curve (AUPRC), calibration, and net benefit. SEPERA was compared against contemporary nomograms (ie, Sayyid nomogram, Soeterik nomogram [non-MRI and MRI]), as well as a separate logistic regression model using the same variables included in SEPERA. An algorithmic audit was performed to assess model bias and identify common patient characteristics among predictive errors. FINDINGS: Overall, 2468 patients comprising 4936 cases (ie, prostatic lobes) were included in this study. SEPERA was well calibrated and had the best performance across all validation cohorts (pooled AUROC of 0·77 [95% CI 0·75-0·78] and pooled AUPRC of 0·61 [0·58-0·63]). In patients with pathological ssEPE despite benign ipsilateral biopsies, SEPERA correctly predicted ssEPE in 72 (68%) of 106 cases compared with the other models (47 [44%] in the logistic regression model, none in the Sayyid model, 13 [12%] in the Soeterik non-MRI model, and five [5%] in the Soeterik MRI model). SEPERA had higher net benefit than the other models to predict ssEPE, enabling more patients to safely undergo nerve-sparing. In the algorithmic audit, no evidence of model bias was observed, with no significant difference in AUROC when stratified by race, biopsy year, age, biopsy type (systematic only vs systematic and MRI-targeted biopsy), biopsy location (academic vs community), and D'Amico risk group. According to the audit, the most common errors were false positives, particularly for older patients with high-risk disease. No aggressive tumours (ie, grade >2 or high-risk disease) were found among false negatives. INTERPRETATION: We demonstrated the accuracy, safety, and generalisability of using SEPERA to personalise nerve-sparing approaches during radical prostatectomy. FUNDING: None.

Impact of cribriform pattern 4 and intraductal prostatic carcinoma on National Comprehensive Cancer Network (NCCN) and Cancer of Prostate Risk Assessment (CAPRA) patient stratification.

Pretreatment classification tools are used in prostate cancer to inform patient management. The effect of cribriform pattern 4 (CC) and intraductal carcinoma (IDC) on such nomograms is still underexplored. We analyzed the Cancer of Prostate Risk Assessment (CAPRA) and National Comprehensive Cancer Network (NCCN) risk scores in cases with and without CC/IDC to assess impact on biochemical recurrence (BCR) and metastases/death of prostate cancer (event free survival-EFS) after prostatectomy. A matched biopsy- prostatectomy cohort (2010-2017) was reviewed for CC/IDC. CAPRA and NCCN scores were calculated. CAPRA score 0-2 were deemed "low", 3-5 "intermediate" and 6-10 "high". NCCN scores 1-2 "very low/low", 3 "favorable intermediate", 4 "unfavorable intermediate", 5-6 "high/very high". Cases were stratified by presence of CC/IDC. BCR and EFS probabilities were estimated using the Kaplan-Meier method. Prognostic performance was evaluated using log-rank tests and Harrell's concordance index. 612 patients with mean age 63.1 years were included with mean follow up of 5.3 (range 0-10.8) years. CC/IDC was noted in 159/612 (26%) biopsies. There were 101 (17%) BCR and 36 (6%) events. CAPRA discriminated three distinct risk categories for BCR (p < 0.001) while only high risk separated significantly for EFS (p < 0.001). NCCN distinguished two prognostic groups for BCR (p < 0.0001) and three for EFS (p < 0.0001). Addition of CC/IDC to CAPRA impacted scores 3-5 for BCR and scores 3-5 and 6-10 for EFS and improved the overall concordance index (BCR: 0.66 vs. 0.71; EFS: 0.74 vs. 0.80). Addition of CC/IDC to NCCN impacted scores 4 and 5-6 and also improved the concordance index for BCR (0.62 vs. 0.68). Regarding EFS, NCCN scores 4 and 5-6 demonstrated markedly different outcomes with the addition of CC/IDC. The CAPRA nomogram allows better outcome stratification than NCCN. Addition of CC/IDC status particularly improves patient stratification for CAPRA scores 3-5, 6-10, and for NCCN scores 4 and 5-6.

Assessment of intravascular granulomas in testicular seminomas and their association with tumour relapse and dissemination.

AIMS: First, to determine the frequency of intravascular granulomas (IVGs) in seminomas and assess for the presence of entrapped seminoma cells. Second, to identify the relationship of this unusual form of vascular space invasion with tumour relapse and/or dissemination. METHODS: 86 cases of seminoma were reviewed to identify IVGs. Immunostaining for OCT3/4 and CD68 was performed. Pathological stage, presence of conventional vascular and rete testis invasion, parenchymal granulomas and follow-up were recorded. Multivariable analysis incorporating tumour size, vascular invasion (conventional granulomas and IVGs) and rete testis invasion was performed. RESULTS: IVGs were identified in 13 cases (13/86). CD68 confirmed histiocytes in all cases. OCT3/4 identified tumour cells in 9/13 seminomas. 27 patients had disease progression with either dissemination at presentation (n=11) or relapse (n=16). Of these 27 patients, 8 had IVG (29.6%). By comparison, 6 of 57 clinical stage 1 seminomas that did not relapse had IVG (10.53%). Multivariable analysis revealed that no single parameter was statistically significant at predicting tumour relapse and/or dissemination (size: HR 1.65; CI 0.71 to 3.82, p=0.24, rete testis invasion: HR 1.04; CI 0.48 to 2.26, p=0.92, lymphovascular space invasion/IVG: HR 1.62; CI 0.65 to 4.01, p=0.30). CONCLUSIONS: IVGs may represent a previously unrecognised form of vascular space invasion in seminomas. Studies on larger cohorts are needed to demonstrate its clinical value.

Prostate cancer localization with multispectral MRI using cost-sensitive support vector machines and conditional random fields.

Prostate cancer is a leading cause of cancer death for men in the United States. Fortunately, the survival rate for early diagnosed patients is relatively high. Therefore, in vivo imaging plays an important role for the detection and treatment of the disease. Accurate prostate cancer localization with noninvasive imaging can be used to guide biopsy, radiotherapy, and surgery as well as to monitor disease progression. Magnetic resonance imaging (MRI) performed with an endorectal coil provides higher prostate cancer localization accuracy, when compared to transrectal ultrasound (TRUS). However, in general, a single type of MRI is not sufficient for reliable tumor localization. As an alternative, multispectral MRI, i.e., the use of multiple MRI-derived datasets, has emerged as a promising noninvasive imaging technique for the localization of prostate cancer; however almost all studies are with human readers. There is a significant inter and intraobserver variability for human readers, and it is substantially difficult for humans to analyze the large dataset of multispectral MRI. To solve these problems, this study presents an automated localization method using cost-sensitive support vector machines (SVMs) and shows that this method results in improved localization accuracy than classical SVM. Additionally, we develop a new segmentation method by combining conditional random fields (CRF) with a cost-sensitive framework and show that our method further improves cost-sensitive SVM results by incorporating spatial information. We test SVM, cost-sensitive SVM, and the proposed cost-sensitive CRF on multispectral MRI datasets acquired from 21 biopsy-confirmed cancer patients. Our results show that multispectral MRI helps to increase the accuracy of prostate cancer localization when compared to single MR images; and that using advanced methods such as cost-sensitive SVM as well as the proposed cost-sensitive CRF can boost the performance significantly when compared to SVM.

Supervised and unsupervised methods for prostate cancer segmentation with multispectral MRI.

PURPOSE: Magnetic resonance imaging (MRI) has been proposed as a promising alternative to transrectal ultrasound for the detection and localization of prostate cancer and fusing the information from multispectral MR images is currently an active research area. In this study, the goal is to develop automated methods that combine the pharmacokinetic parameters derived from dynamic contrast enhanced (DCE) MRI with quantitative T2 MRI and diffusion weighted imaging (DWI) in contrast to most of the studies which were performed with human readers. The main advantages of the automated methods are that the observer variability is removed and easily reproducible results can be efficiently obtained when the methods are applied to a test data. The goal is also to compare the performance of automated supervised and unsupervised methods for prostate cancer localization with multispectral MRI. METHODS: The authors use multispectral MRI data from 20 patients with biopsy-confirmed prostate cancer patients, and the image set consists of parameters derived from T2, DWI, and DCE-MRI. The authors utilize large margin classifiers for prostate cancer segmentation and compare them to an unsupervised method the authors have previously developed. The authors also develop thresholding schemes to tune support vector machines (SVMs) and their probabilistic counterparts, relevance vector machines (RVMs), for an improved performance with respect to a selected criterion. Moreover, the authors apply a thresholding method to make the unsupervised fuzzy Markov random fields method fully automatic. RESULTS: The authors have developed a supervised machine learning method that performs better than the previously developed unsupervised method and, additionally, have found that there is no significant difference between the SVM and RVM segmentation results. The results also show that the proposed methods for threshold selection can be used to tune the automated segmentation methods to optimize results for certain criteria such as accuracy or sensitivity. The test results of the automated algorithms indicate that using multispectral MRI improves prostate cancer segmentation performance when compared to single MR images, a result similar to the human reader studies that were performed before. CONCLUSIONS: The automated methods presented here can help diagnose and detect prostate cancer, and improve segmentation results. For that purpose, multispectral MRI provides better information about cancer and normal regions in the prostate when compared to methods that use single MRI techniques; thus, the different MRI measurements provide complementary information in the automated methods. Moreover, the use of supervised algorithms in such automated methods remain a good alternative to the use of unsupervised algorithms.

Morphological assessment of radical prostatectomy specimens. A protocol with clinical relevance.

The increase in prostate cancer detection has induced a sharp increase in the number of radical prostatectomies Proper examination of radical prostatectomy (RP) specimens by pathologists is critical in determining the need for adjuvant treatment and prediction of patient outcome. The pathology report should include relevant clinical information as well as provide prognostically useful information derived from the macroscopic examination and microscopic evaluation of the RP specimen