seminal vesicle invasion
Also written as: SVI — seminal vesicle invasion
Prostate cancer infiltration into the seminal vesicles, representing pT3b disease with poor prognosis.
Full Definition
Seminal vesicle invasion (SVI) occurs when prostate cancer extends into the seminal vesicle wall or lumen, representing pT3b disease in the TNM staging system. This finding indicates locally advanced prostate cancer with significantly worse prognosis compared to organ-confined disease or extracapsular extension alone. SVI is associated with higher risk of biochemical recurrence, distant metastasis, and cancer-specific mortality. Detection may occur preoperatively through imaging studies or at final pathology following radical prostatectomy. The presence of SVI typically necessitates adjuvant therapy discussions.
Usage
Usage note: Often abbreviated as SVI. Represents more advanced disease than extracapsular extension and carries worse prognosis.
In Context
- "Bilateral seminal vesicle invasion was confirmed on the radical prostatectomy specimen, upstaging the patient to pT3b." — Pathology report
- "Given the seminal vesicle invasion, the patient was counseled regarding adjuvant radiation therapy." — Post-operative consultation note