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 connects with vertebral veins, this is thought to be the route of bone metastasis of prostate cancer.
^"Male Genitals - Prostate Neoplasms". Pathology study images. University of Virginia School of Medicine. Archived from the original on 2011-04-28. Retrieved 2011-04-28. "There are many connections between the prostatic venous plexus and the vertebral veins. The veins forming the prostatic plexus do not contain valves and it is thought that straining to urinate causes prostatic venous blood to flow in a reverse direction and enter the vertebral veins carrying malignant cells to the vertebral column."