Computer-aided diagnosis system for characterizing ISUP grade≥2 prostate cancers at multiparametric MRI: A cross-vendor evaluation.

PURPOSE: To assess the performance of a computer-aided diagnosis (CADx) system trained at characterizing International Society of Urological Pathology (ISUP) grade≥2 peripheral zone (PZ) prostate cancers on multiparametric magnetic resonance imaging (mpMRI) examinations from a different institution and acquired on different scanners than those used for the training database. PATIENTS AND METHODS: Preoperative mpMRIs of 74 men (median age, 65.7 years) treated by prostatectomy between 2014 and 2017 were retrospectively selected. One radiologist outlined suspicious lesions and scored them using Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2); their CADx score was calculated using a classifier trained on an independent database of 106 patients treated by prostatectomy in another institution. The lesions' nature was assessed by comparison with prostatectomy whole-mounts. Diagnostic accuracy was estimated with areas under receiver operating characteristic curves (AUCs). Sensitivity and specificity were calculated using a CADx threshold (≥0.21) that yielded 95% sensitivity in the training database, and a PI-RADSv2≥3 threshold. RESULTS: A total of 127 lesions (PZ, n=104; transition zone [TZ], n=23) were described. In PZ, CADx and PI-RADSv2 scores had similar AUCs for characterizing ISUP grade≥2 cancers (0.78 [95% confidence interval (CI): 0.69-0.87] vs. 0.74 [95%CI: 0.62-0.82], respectively) (P=0.59). Sensitivity and specificity were respectively 89% (95%CI: 82-97%) and 42% (95%CI: 26-58%) for the CADx score, and 97% (95%CI: 93-100%) and 37% (95%CI: 22-52%) for the PI-RADSv2 score. In TZ, both scores showed poor specificity. CONCLUSION: In this external cohort, the CADx and PI-RADSv2 scores showed similar performances in characterizing ISUP grade≥2 cancers.

[Prevalence and diversity of management of prostate cancer patients classified as low risk using D'Amico group or Cancer of the Prostate Risk Assessment (CAPRA) score: A French multicenter study]. / Prévalence et diversité de la prise en charge des patients atteints de cancer de la prostate classés à faible risque selon la classification de d'Amico ou le score de CAPRA : étude française multicentrique.

OBJECTIVES: Currently, the French High Authority for Health does not recommend mass screening for prostate cancer (PCa), due to the risk of over-treatment, notably of low risk patients. Our study is intended to reflect the therapeutic attitudes for the management of patients classified as low risk of progression in French clinical centers. METHODS: For all positive prostate biopsies performed during 2012 and 2013 in five French departments of urology, clinicopathological characteristics required to calculate the d'Amico risk group and the Cancer of the Prostate Risk Assessment (CAPRA) score were filled. Information on the first treatment of "low risk" patients was collected. RESULTS: A total of 1035 patients were included, with a median age at diagnosis of 66 years old. According to d'Amico and CAPRA classifications, 30.4% and 35.0% of patients were at low, 34.5% and 33.2% at intermediate, 35.1% and 31.8% at high risk. The diagnosis severity increased with age (P<0.0001). The main treatment for low risk patients was radical prostatectomy (41.6% and 42.0% for d'Amico and CAPRA, respectively), but active surveillance was the most frequent treatment if diagnosed after 75 years old. The management of low risk patients varied significantly between centers (P<0.0001), according to the therapeutic platforms available within the hospital. CONCLUSIONS: In absence of strong progression predictor, the management of low risk PCa remains based on center habits and local therapeutic platforms. New predictive markers, such as multiparametric MRI or molecular tests, are needed to guide rational management of low risk PCa. LEVEL OF EVIDENCE: 4.

Detection of Foxp3+ cells on biopsies of kidney transplants with early acute rejection.

This retrospective study was conducted to examine whether the presence of Foxp3+ cells in biopsies of kidney transplants displaying early acute rejection (AR) predicted the outcome of the episode. Seventeen biopsies showing AR included in this study were obtained at 42 +/- 30 days after transplantation. Lesions were graded according to the Banff classification. Foxp3 staining was performed on paraffin-embedded sections with a monoclonal antibody after antigen retrieval. We evaluated relationships between the number and the location of Foxp3+ cells, the type of rejection, and the serum creatinine value at 1 year. Foxp3+ cells were detected in 11 of 17 biopsies with AR (9.5 +/- 13.3 cells/mm(2)). These elements were mixed with other interstitial inflammatory cells. Intraepithelial tubular Foxp3+ cells were seen in 9 biopsies (1.5 +/- 2.5 cells/mm(2)). Foxp3+ cells were associated with borderline lesions (25.5 +/- 22.4/mm(2)); type 1 AR (7.18 +/- 9/mm(2)) and type 2 AR (1.99 +/- 3.46/mm(2)). The average number of cells per field was not different in C4d(+) and C4d(-) AR (6 +/- 8.35 vs 8.5 +/- 14.7/mm(2)). Graft loss within the first year was higher among the group of recipients without Foxp3+ cells (3/6) than those with Foxp3+ cells (0/11). All AR with intraepithelial tubular Foxp3 cells had favorable outcomes. Foxp3 has been proposed as a relevant marker of CD4(+)CD25(+) regulatory T cells. This study showed that Foxp3+ cells can be detected in kidney transplant biopsies with AR. The absence of Foxp3+ cells, especially in epithelial tubular cells, might indicate a poor prognosis following an AR episode.

Recurrence of IgA nephropathy with crescents in kidney transplants.

Crescentic IgA nephropathy is an uncommon finding in native kidneys (3%-5%) and in renal transplants. This study was performed to determine the frequency of relapsing crescentic IgA nephropathy after kidney transplantation. Over a 15-year period, 42 patients (25 men, 17 women) of age range 17 to 59 years with biopsy-proven IgA nephropathy in their native kidneys were entered into this retrospective study, because they had undergone kidney transplantation and had sequential allograft biopsies during their follow-up. Mean follow-up after transplantation was 8.9 years (range, 1-15 years). In their native kidneys, 5 patients (12%) had more than 20% crescents, and only 2 (5%) had more than 50% of glomeruli involved. As expected, 52.4% of recipients showed recurrent mesangial IgA deposits in their kidney grafts. The 2 patients with diffuse crescentic IgA nephropathy in their native kidneys experienced acute graft dysfunction at 15 and 47 months. Graft biopsy showed recurrent IgA deposits with cellular crescents in 30% and 20% of glomeruli, respectively. Despite corticosteroid pulse therapy, graft failures occurred 2 and 27 months later. No crescentic proliferation was observed during follow-up in any other case. Only 5 other grafts failed because of chronic allograft nephropathy, without any relationship to the relapse of IgA deposits. These data suggested for the first time that only diffuse crescentic IgA nephropathy in the native kidneys was associated with the occurrence of crescents in the kidney transplants, a finding that raises the possibility of a particular subgroup of IgA nephropathies.