Prostatic venous plexus
The prostatic veins form a well-marked prostatic plexus which lies partly in the fascial sheath of the prostate and partly between the sheath and the prostatic capsule. It communicates with the pudendal and vesical plexuses.
The prostatic venous plexus drains into the internal iliac vein which connects with the vertebral venous plexus, this is thought to be the route of bone metastasis of prostate cancer.
It is sometimes known as "Santorini's plexus," named for the Italian anatomist Giovanni Domenico Santorini.