760 Histopathologic Characteristics of Prostatic Adenocarcinoma Showing Microscopic Bladder Neck Invasion on Radical Prostatectomy
Recommended Citation
Agarwal P, Lira Diaz A, Hassan O, Dadhania V, Alhamar M, Al-Obaidy K, Gupta N. 760 Histopathologic Characteristics of Prostatic Adenocarcinoma Showing Microscopic Bladder Neck Invasion on Radical Prostatectomy. Lab Invest 2025; 105(3).
Document Type
Conference Proceeding
Publication Date
3-24-2025
Publication Title
Lab Invest
Keywords
adult, African American, aged, bladder neck, cancer staging, Caucasian, conference abstract, controlled study, histopathology, human, human tissue, major clinical study, male, metastasis, prostate, prostate adenocarcinoma, prostate cancer, radical prostatectomy, retrospective study, seminal vesicle, surgery, tumor volume
Abstract
Disclosures: Priti Agarwal: None; Antonio Lira Diaz: None; Oudai Hassan: None; Vipulkumar Dadhania: None; Mohamed Alhamar: None; Khaleel Al-Obaidy: None; Nilesh Gupta: None Background: The current AJCC/TNM staging system for prostate cancer classifies microscopic bladder neck invasion (mBNI) or extension of prostatic adenocarcinoma (PCa) into surrounding soft tissue into one broad category/T stage of pT3a/extraprostatic extension (EPE). While the characteristics of tumors with soft tissue extension are well studied, it remains unclear whether tumors exhibit similar aggressive histopathologic features in cases of mBNI. Our study aims to highlight the tumor characteristics associated with mBNI in patients undergoing radical prostatectomy (RP). Design: We reviewed 2,080 cases of RP, from our hospital database from 2012-2016 to assess for presence of microscopic bladder neck invasion (mBNI). 77 patients (3.7%) were identified as having mBNI, with or without extraprostatic extension (EPE) elsewhere in the prostate. The data collected included patient age at the time of surgery, race, tumor location, percent of tumor volume (%TV), Grade Group (GG), margin status, seminal vesicle invasion (SVI) and lymph nodes metastasis (LNM). Results: Of the 77 cases with mBNI, 21 (27.3%) had mBNI without EPE, while 56 (72.7%) had additional EPE elsewhere. mBNI was significantly more common (p<0.05) in African American (AA) patients (57.1%) compared to Caucasians (38%) . Tumors in this group were predominantly located anteriorly (81%), compared to the more extensive anterior + posterior location (42%) observed in the mBNI + EPE group. The % TV was significantly lower (p=0.0026) in the mBNI group (19%) compared to the mBNI + EPE group (37%). Additionally, tumors in the mBNI group were generally of a lower grade (81% GG2) compared to those in the mBNI + EPE group, where the majority were GG3 or higher (60%). No evidence of SVI or LNM was observed in the mBNI group, whereas the mBNI + EPE group had a 41% incidence of SVI and 35.7% incidence of LNM. Statistical analysis was performed using Chi-square and two-tailed, unpaired t-test. The findings are summarized in the table below: [Formula presented] Conclusions: Tumors with mBNI, in the absence of EPE elsewhere, exhibit markedly different characteristics compared to those with mBNI+ EPE. These tumors are predominantly located anteriorly, with lower %TV and grade (mainly GG2), and lack other adverse features such as SVI or LNM. In contrast, the mBNI + EPE group shows more extensive/ anterior +posterior involvement, larger %TV, and a high incidence of SVI and LNM. We propose that mBNI without EPE be reclassified under a distinct pT stage subcategory, intermediate between organ confined (pT2) and EPE (pT3a).
Volume
105
Issue
3
