Common causes of testicle swelling include hydrocele, varicocele, testicular cysts, testicular torsion, and, in some cases, testicular cancer. Each of these conditions has been known to cause testicular swelling, though not all individuals will experience pain associated with the inflammation. In the majority of cases, swollen testicles will either be enlarged or possess a noticeable lump, both of which can be detected with an at-home testicular self-exam.
Hydrocele is a buildup of fluid in the testes and is one of the most common causes of testicle swelling. There is a pair of membranes that encompass the testicle, and when fluid gets trapped between these membranes, hydrocele results. The scrotal swelling associated with hydrocele is typically painless and goes away of its own accord. If the condition persists, draining of the testicles or surgery are both viable options.
When blood in the spermatic vein is blocked, varicose veins can develop around the testicles. This condition is called varicocele and is also quite common; studies indicate that approximately 15% of all men will experience varicocele. In treating testicle swelling for varicocele, surgery can be performed, but this measure is only undertaken when the patient's fertility is at risk. In most cases, varicocele is not serious and will dissipate in time.
Testicular cysts, or spermatocele, are tiny sacs containing fluid that develop on the small connecting tubes at the back of the testes. Spermatocele also contain a buildup of sperm, but the condition is relatively pain-free and not at all critical. If the cysts are so large that they are noticeable through the scrotum, a patient can have the cysts drained or undergo surgery.
Two rarer but not unheard-of causes of testicle swelling are testicular torsion and testicular cancer. In the case of testicular torsion, the spermatic cord becomes twisted and blood can no longer successfully flow to the testicle. This is a serious condition since the lack of blood can kill the testicle, forcing surgical removal and possible infertility. Symptoms of testicle swelling in patients with testicular torsion include pain associated with the swelling, nausea, fever, and fainting.
An early sign of testicular cancer is testicle swelling. The swelling is usually accompanied by a certain amount of pain, though this is not always the case. Small, hardened lumps may also develop on the testes. While this type of swelling is seldom reason for alarm, medical professionals encourage men with these symptoms to see a doctor immediately to either confirm or reject a cancer diagnosis.