A new paper  is the trigger for this post.
"Varicoceles occur in around 15% of all men." 
"A varicocele is an abnormal enlargement of the pampiniform venous plexus in the scrotum." 
The issue of varicoceles in PCa, is that a huge amount of free testosterone [T] is potentially directed to the prostate. Serum T levels may be normal, but prostatic cells have an abnormally high exposure.
Gat has been studying varicoceles for many years. The new study involves BPH patients, but I have known one man with PCa & an intact prostate, who figured that it was essential for him to get his varicoceles treated if he was to survive PCa. It's a subject that rarely arises.
"In varicocele, there is venous flow of free testosterone (FT) directly from the testes into the prostate. Intraprostatic FT accelerates prostate cell production and prolongs cell lifespan, leading to the development of BPH. We show that in a large group of patients presenting with BPH, bilateral varicocele is found in all patients. A total of 901 patients being treated for BPH were evaluated for varicocele. Three diagnostic methods were used as follows: physical examination, colour flow Doppler ultrasound and contact liquid crystal thermography. Bilateral varicocele was found in all 901 patients by at least one of three diagnostic methods. Of those subsequently treated by sclerotherapy, prostate volume was reduced in more than 80%, with prostate symptoms improved. A straightforward pathophysiologic connection exists between bilateral varicocele and BPH. The failure of the one-way valves in the internal spermatic veins leads to a cascade of phenomena that are unique to humans, a result of upright posture. The prostate is subjected to an anomalous venous supply of undiluted, bioactive free testosterone. FT, the obligate control hormone of prostate cells, reaches the prostate directly via the venous drainage system in high concentrations, accelerating the rate of cell production and lengthening cell lifespan, resulting in BPH."