Radical prostatectomy. Prognostic value of positive surgical margins in pT2 patients

We intend to assess the prognostic influence of surgical margins on the biochemical progression free survival (BPFS) in patients classified as pT2 after radical prostatectomy.

We analyze a series of 1,132 T1-T2 patients with prostate cancer treated with radical prostatectomy between 1989-2009. PT3b, pT4 and patients with lymph node involvement were excluded from the series. The clinicopathologic variables and the BPFS of pT2(+), pT2(-) and pT3 patients are compared. The influential clinicopathologic variables in the BPFS are identified in the pT2(+) group and risk groups are designed.

Of 1,051 patients evaluated finally: 598 (59,6) were pT2(-) 163 (15,5%) pT2(+)80 (7,6%) pT3a(-) and 210 (20%) pT3(+). Clinical characteristics of pT2(+). It is homogeneous with the pT2(-) group and significantly better than pT3(+) group in all the clinicopathologic variables evaluated. 5 and 10 year BPFS of the pT2(68 ± 3% and 57 ± 5%) is significantly worse than pT2( -)(87 ± 1% and 79 ± 2%), similar to pT3a(-) (75 ± 5% and 64 ± 7%and better than pT3(+) (44 ± 3% and (36 ± 3%) BPFS pT2(+) influential factors: Univariate study : Pathological Gleason score 7-10 (HR:2.1 95% IC: 1.1-4.1), (p=0.02)MRI that indicates T3 (HR:3.2 95%IC: 1.4-7.3), (p=0.04) PSA > 15 ng-ml (HR:4 95% IC: 2-8.2), (p < 0.0001) and high risk D'Amico group (HR:3.3 95%IC: 1.3-8.5), (p=0.01) are influential variables. A risk model with the involved variables can be designed. Each variable present is a point. Two groups are designed : Group 1 (0-1 variable) Group 2 (2-3 variables). 5 and 10 year BPFS for Group 1 are 71±5% and 69 ± 5%, and are 37 ± 12% and 22 ± 11% for Group 2. (p < 0.0001).

Surgical margins in pT2 patients have independent influence in the BPFS. The group is heterogeneous and it can be divided into two risk groups accordingly to the BPFS influential variables: a larger group (86% pT2(+) with worse prognosis than pT2(-), and a smaller group (remaining 14%) with similar prognosis to pT3 (+).It is likely that pT2(+) patients are a mixture of understaged patients with others with iatrogenic margins or false margins due to poor assessment of the surgical specimen.