Objective: To test the ability of two of the most stringent criteria used to identify patients with low-risk prostate cancer suitable for active surveillance (AS) to correctly exclude patients with unfavourable prostate cancer characteristics.
Patients and methods: The study included 874 consecutive patients treated with radical prostatectomy (RP). We selected patients who could have been selected for AS according to the van den Bergh et al. and the Carter et al. criteria. We analysed the rates of advanced disease in these patients, defined as presence of either extracapsular extension (ECE), seminal vesicle invasion (SVI), lymph node invasion (LNI) and Gleason sum of 8-10 or 7-10.
Results: Of 874 patients, 85 (9.7%) and 61 (6.9%) patients, respectively, qualified for AS according to the tested criteria. Within the van den Bergh et al. candidates, 5.9, 1.2, 1.2 and 1.2% of patients, respectively, showed ECE, SVI, LNI and high-grade Gleason sum 8-10 at pathology. Within the Carter et al. candidates, 3.3, 0, 3.3 and 0% of patients, respectively, showed ECE, SVI, LNI and high-grade Gleason sum 8-10. The cumulative rate of unfavourable characteristics was 7.1 and 3.3%. The rate increased to 28.2 and 27.9%, respectively, when Gleason sum 7 was considered as an unfavourable prostate cancer.
Conclusions: The use of the strictest criteria for AS inclusion identified 7-10% of the men in our cohort of men undergoing RP, as men that would have been eligible for AS. Among this small proportion, between 3.3 and 7.1% of patients harboured unfavourable prostate cancer characteristics. The clinical implications of these misclassification rates remain to be determined.