Short (≤1 mm) positive surgical margin and risk of biochemical recurrence after radical prostatectomy

Abstract

What's known on the subject? and What does the study add? It has been suggested that a very short positive margin does not confer additional risk of BCR after radical prostatectomy. This study shows that even very short PSM is associated with increased risk of BCR. Objective To re‐evaluate, in a larger cohort with longer follow‐up, our previously reported finding that a positive surgical margin (PSM) ≤1 mm may not confer an additional risk for biochemical recurrence (BCR) compared with a negative surgical margin (NSM). Patients and Methods Margin status and length were evaluated in 2866 men treated with radical prostatectomy (RP) for clinically localized prostate cancer at our institution from 1994 to 2009. We compared the BCR‐free survival probability of men with NSMs, a PSM ≤ 1 mm, and a PSM < 1 mm using the Kaplan–Meier method and a Cox regression model adjusted for preoperative prostate‐specific antigen (PSA) level, age, pathological stage and pathological Gleason score (GS). Results Compared with a NSM, a PSM ≤ 1 mm was associated with 17% lower 3‐year BCR‐free survival for men with pT3 and GS ≥ 7 tumours and a 6% lower 3‐year BCR‐free survival for men with pT2 and GS ≤ 6 tumours (log‐rank P < 0.001 for all). In the multivariate model, a PSM ≤ 1 mm was associated with a probability of BCR twice as high as that for a NSM (hazard ratio [HR] 2.2), as were a higher PSA level (HR 1.04), higher pathological stage (HR 2.7) and higher pathological GS (HR 3.7 [all P < 0.001]). Conclusion In men with non‐organ‐confined or high grade prostate cancer, a PSM ≤ 1 mm has a significant adverse impact on BCR rates.

Results of surgery for high-risk prostate cancer

“…The importance of PSM has already been confirmed in recent studies, which have associated PSM characteristics, such as number and length of PSM and Gleason score at the margin site, to a higher risk of biochemical recurrence [65][66][67]. From this point of view, the possibility to predict presence of specimen-confined disease (SCD) (pT2-3a, R0, N0) could help clinicians to select patients who might benefit from radical prostatectomy monotherapy.…”

Biochemical recurrence risk factors in surgically treated high and very high-risk prostate tumors

“…Traditionally considered as a tumor that develops over the long term, its high and very high-risk variants have been shown to behave in a very variable manner [3,4], with an irregular prognosis, which normally leads to the need for a multiple treatment approach to achieve appropriate cancer control [5,6]. This situation has spawned numerous works attempting to analyse the different preoperative (PSA, digital rectal examination, age, prostate Gleason score, uni/bilateral tumor involvement, percentage of affected cylinder, etc.)…”

Prognostic Significance of Positive Surgical Margins and Other Implications of Pathology Report

“…In a retrospective study by eastham et al examining the outcome of 2442 RPs, isolated posterolateral and posterior PSMs were an independent risk factor (HR 2.8, 95% CI 1.8-4.4 and HR 2.0 (95% CI 1.1-3.6, respectively)) for BCR compared to negative margins whereas other margin sites were not independently associated with BCR in their cohort. [50][51][52] Furthermore, the difference in the risk of BCR between close margins and PSMs was insignificant in the study by Izard et al 51 The proposed mechanism for close margins is that with additional sampling levels, a close margin may actually be positive. While some studies have reported higher risk of biochemical recurrence 43-45 others have not.…”