What is a Spermatocele or Spermatic Cyst?

A spermatocele (or spermatic cyst) is a fluid-filled sac that grows in the epididymis. The epididymis is a tightly coiled tube about 20 feet long where the sperm matures as it passes through. It's located in the scrotum and surrounds the back and top of the testicle. 

Spermatoceles vary in size. They typically don’t hurt, but they could cause pain if they grow too large. Spermatoceles can be smooth. They might also be filled with a whitish, cloudy fluid. Sometimes, they hold sperm. Most of the time, they’re benign (not cancerous). Still, if you notice a growth near or in your penis or scrotum (the pouch that holds your testicles), see your doctor to have it checked.

It is important to remember that spermatoceles do not impact fertility.

What Causes Them?

Spermatoceles often contain pools of dead sperm. Doctors aren’t sure what causes this. Often, spermatoceles develop for no specific reason at all.

They’re actually quite common. About three out of 10 men will get them at some point in their lives. Men between ages 20 to 50 are most likely to get them.

How Do I Know If I Have One?

Most of the time, spermatoceles don’t hurt, so you may not have any symptoms. You might only feel a bump while examining your testicles. Your doctor might find it during an exam. As the cyst gets bigger, you may feel heaviness in your testicle. You might also notice a mass or swelling behind or above your testicle.

Your doctor will likely do a couple of tests to make sure the growth is a spermatocele and not a tumor. He’ll probably start with a physical exam. Then he’ll follow up with a transillumination or an ultrasound.

Transillumination is where your doctor shines a light through your scrotum. If it’s a spermatocele, the light will shine through it. If it is a mass, it won't. 

Ultrasound is the next step if transillumination doesn’t show fluid. This test uses high-frequency sound waves to create images on a screen.


How Are Spermatoceles Treated?

Most of the time, they’re not. Your doctor may prescribe pain relievers to make you more comfortable. 

Aspiration is a procedure that can help relieve some of the pain and pressure of spermatoceles. Your doctor will insert a needle into the cyst to remove some of the fluid.

If the cyst refills and comes back, your doctor can do a procedure called a sclerotherapy. He’ll drain some of the fluid from the spermatocele. Then he’ll use a substance that causes the sac to fill with scar tissue. This tissue could lower the risk of the spermatocele coming back. But it can damage the epididymis. Your doctor may only suggest this option if you’re not interested in having children.

In rare cases (if the spermatocele is getting in the way of your daily life), your doctor could remove it through surgery. He’ll numb the area, make a small incision (cut) in your scrotum or groin, and remove the growth.

WebMD Medical Reference Reviewed by Sabrina Felson, MD on March 29, 2019



Cleveland Clinic: “Spermatocele.”

Mayo Clinic: “Spermatocele.”

Michigan Institute of Urology: “Spermatocele.”

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