Word count abstract: Word count text :2 ABSTRACT Purpose: To evaluate and compare the pathological findings and the PSA outcomes after radical prostatectomy (RP) in men eligible for AS, according to 3 different biopsy inclusion criteria.
Materials and Methods:The study population included 177 men eligible for AS who fulfilled clinico-biological criteria (Gleason score ≤6, PSA<10, clinical stage T1c) and biopsy criteria as follows: (1) <3 positive cores and <3 mm of total tumour length; (2) and/or <3 positive cores with a cancer involvement <50% in any core; (3) and/or <33% of positive cores. PSA density cut-offs of 15 and 20 ng/ml/gr were also studied among these groups. Pathological findings on RP specimens and biochemical recurrence-free survival (RFS) were studied. Median follow-up was 34 months.Results: Cancers were graded Gleason 7 on RP specimens from 48.3% to 55.4% of cases. The rates of extracapsular extension (ECE) and vesicle seminal invasion (SVI) ranged from 11.2% to 17.5%, and from 1.1% to 1.8%, respectively, regardless of PSA density. The use of PSA density as AS criterion decreased for AS by 1.4-fold and by 2.3-fold the number of men eligible according to the cut-off used. The risk of unfavourable disease (defined as pT3-4 stage and/or a Gleason score≥8) remained between 15% to 19.2% when a PSA density cut-off of 15 ng/ml/gr was used. The risk of overall unfavourable disease was significantly higher in men with a cancer involvement ≥3 mm in initial biopsy compared with men who fulfilled these most stringent biopsy criteria (27.3%, vs 13.5%, respectively; p=0.023). The 3-year biochemical RFS was 91.5% and was not affected by the 3 different AS definitions.
Conclusions:Even with the use of a 21-core biopsy protocol, the rate of unfavourable disease on RP specimens remains still elevated in men eligible for AS. Patients must be informed of this risk of misclassification which is about 20% in men who fulfil the less stringent biopsy criteria.