Short (≤1 mm) positive surgical margin and risk of biochemical recurrence after radical prostatectomy
Correspondence: Sergey Shikanov, University of Chicago Medical Center, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.
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.
- 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).
- 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]).
- In men with non-organ-confined or high grade prostate cancer, a PSM ≤ 1 mm has a significant adverse impact on BCR rates.