Purpose: We assess the pathological mechanisms of silent prostatic stromal
invasion in patients with bladder cancer for early detection and treatment.
Materials and Methods: Between August 1998 and January 1999, 10 patients wi
th clinically organ confined transitional cell carcinoma of the bladder and
known prostatic stromal invasion on transurethral biopsy or who were high
risk for prostatic involvement due to tumor location near the bladder neck
were studied for histological patterns of prostatic invasion. There were 5
cystectomy specimens distended for 24 hours with formalin via a Foley cathe
ter, then step sectioned longitudinally at 3 mm. intervals through the blad
der neck and prostate. Standard hematoxylin and eosin staining methods were
used and sections were analyzed by 2 pathologists.
Results: There were 3 separate patterns of prostatic stromal invasion eluci
dated, including 2 previously described methods of extravesical or intraure
thral invasion into the prostatic stroma and a third one through the bladde
r neck directly into the prostatic stroma. The third pattern was not grossl
y evident on endoscopy or urethral biopsy before cystectomy.
Conclusions: Longitudinal sectioning of the bladder neck and prostate of cy
stectomy specimens suggests tumors at the bladder neck may directly invade
the prostatic stroma without histological evidence of extravesical or intra
urethral spread. Such direct silent tumor invasion of the prostate by super
ficial or endoscopically inapparent tumor is difficult to detect clinically
by current biopsy methods. New methods of detection are necessary.