Sub-Classification of Extracapsular Extension in Prostate Cancer (PCA): Does It Matter? Prognostic Significance from a Study of 675 Patients at a Large Academic Institution
Milon Amin, Joel B Nelson, Elen Woldemichael, Anil V Parwani, Rajiv Dhir. University of Pittsburgh Medical Center, Pittsburgh, PA; Unversity of Pittsburgh Medical Center, Pittsburgh, PA
Background: The finding of extracapsular extension (ECE) in a radical prostatectomy (RP) specimen is a poor prognostic factor. ECE has been divided into 'focal' (<0.8 mm) and 'established' (≥0.8 mm). Our reporting format also uses a third category, 'multifocal,' defined as more than one ECE focus, with each focus <0.8 mm. We examined the significance of this third category of ECE for predicting biochemical recurrence rate (BCRR) following RP.
Design: We examined follow-up data on 675 men with stage pT3a/pT3b PCA, from a cohort of 2691 men. Patients were separated into groups based on 12 variables, including Gleason scores, volume of prostatic involvement (≤25%, >25%), tertiary grade 5, seminal vesicle invasion, perineural invasion, angiolymphatic invasion, positive lymph nodes and positive margins. The BCRR was calculated for each group, adjusting for these variables. Biochemical recurrence (BCR) was defined as a post-operative PSA ≥0.2 ng/mL or initiation of any adjuvant therapy.
Results: Of 675 patients with stage pT3a/pT3b disease, 324 (48%) had focal ECE, 93 (14%) had multifocal ECE and 258 (38%) had established ECE. 205 (30.4%) had BCR. The median follow-up time was 49.84 months. BCRRs adjusted for the 12 variables are summarized in Table 1.
|Variable||# Patients||# with BCR||BCR Rate (Focal ECE)||BCR Rate (Multi-focal ECE)||BCR Rate (Established ECE)|
|Tertiary grade 5||190||58||0.05||0.08||0.17|
|Seminal vesicle invasion||134||85||0.1||0.19||0.34|
|(+) Lymph nodes||62||44||0.06||0.23||0.4|