The significance of positive surgical margin in areas of capsular incision in otherwise organ confined disease at radical prostatectomy

Abstract

Purpose: The significance of capsular incision into tumor at radical prostatectomy with otherwise organ confined tumor is not well understood.

Materials and methods: Inclusion criteria were positive margin in an area of capsular incision, no extraprostatic extension elsewhere, negative seminal vesicles and lymph nodes, entire prostate submitted for examination, and no neoadjuvant therapy.

Results: The postoperative progression of 135 cases of radical prostatectomy with capsular incision (1.3% of radical prostatectomies 1993 to 2004) was compared to 10,311 radical prostatectomies without capsular incision. Mean tumor length at the capsular incision site was 2.6 mm. Capsular incision was posterolateral (61.5%), posterior (18.5%), anterior (8.9%), lateral (8.1%) and apical (3%). The 5-year actuarial freedom from biochemical recurrence for tumors with capsular incision was worse (71.3%) than organ confined margin negative tumor (96.7%) (p <0.0001) and focal extraprostatic extension margin negative disease (89.7%) (p = 0.02), yet better than extensive extraprostatic extension margin positive tumors (58.5%) (p <0.0001). The risks of progression in men with capsular incision, focal extraprostatic extension margin positive and extensive extraprostatic extension margin negative disease were not significantly different. Risk of recurrence correlated with tumor length at the capsular incision site (p = 0.002). The 5-year risks of biochemical progression were 20.0% and 55% for less than 3 mm and 3 mm or greater of tumor cut across, respectively.

Conclusions: Isolated capsular incision into tumor is uncommon in cases of radical prostatectomy performed by experienced urologists, typically Gleason score 6, and most common in the neurovascular bundle region. Isolated capsular incision has a higher recurrence rate than organ confined or focal extraprostatic extension margin negative disease, yet a lower recurrence rate than extensive extraprostatic extension margin positive tumor, and a worse prognosis with greater extent of capsular incision.