Spermatocele

A spermatocele is a fluid-filled sac that develops near the testicle. It’s usually painless, not cancerous, and often goes unnoticed. While most men never need treatment, understanding this common condition can help ease worry if you discover a lump in your scrotum.

Table of contents

• What is a spermatocele?
• Other names
• Associated anatomy
• How common is it?
• What causes a spermatocele?
• Symptoms
• When to see a doctor
• How is it diagnosed?
• Treatment options
• Impact on fertility
• What to expect

What is a spermatocele?

A spermatocele is an abnormal sac, also called a cyst (a fluid-filled growth), that develops in the epididymis — a small, coiled tube located on the upper testicle that collects and transports sperm^[1]. The cyst is usually filled with milky or clear fluid that might contain sperm^[1].

This condition is noncancerous and generally painless. A spermatocele develops above or behind each testicle and feels like a smooth, firm lump in the scrotum on top of the testicle^[4]. The size can vary considerably — from several millimeters to many centimeters^[3].

Most spermatoceles are small and may look like a pea-sized lump that sits right above or behind a testicle. Some spermatoceles are so tiny they cannot be seen or felt at all, and healthcare providers can only detect them with imaging tests like ultrasound. In rare cases, spermatoceles can grow large enough that they appear as though you have a third testicle^[2].

spermatic cyst, epididymal cyst

Other names

Spermatoceles are also known by other names. Healthcare providers may call them spermatic cysts or epididymal cysts^[1].

It is important to note that while “epididymal cyst” has been used interchangeably with “spermatocele,” there are differences between them. Epididymal cysts may appear anywhere along or within the epididymis and do not contain sperm, whereas spermatoceles may contain sperm^[3]. Epididymal cysts have been shown to occur more frequently in children before reaching puberty^[3].

Associated anatomy

• Epididymis
• Testicle (testis)
• Scrotum

The epididymis is a long, tightly coiled tube that lies above and behind each testicle. Its main job is to store and transport sperm from the testicle^[2]. Spermatoceles form in this tube structure.

How common is it?

Spermatoceles are fairly common. They affect nearly 1 in 3 adult males^[2]. It is estimated that approximately 30 percent of men have been diagnosed with small spermatoceles^[3].

Spermatoceles usually affect men who are middle-aged and most commonly appear in midlife, in the 40s or 50s^[2]. The incidence of spermatoceles increases as men age^[3]. While they can occur at any age, they are rare in children. The incidence rate is around 5 to 20 percent for children^[3].

What causes a spermatocele?

The exact cause of spermatoceles is unknown^[1]. Healthcare providers don’t fully understand what causes sperm to build up in the epididymis^[2].

Spermatoceles occur when sperm builds up somewhere in the epididymis. Some experts believe that a blockage in the epididymal duct (the tube that carries sperm) or inflammation may be potential causes^[2]. The condition might result from a blockage in one of the multiple tubes within the epididymis that transport and store sperm from the testicle^[1].

In many cases, spermatoceles appear without any sign of injury, bacterial infection, or other obvious cause^[2]. Although the cause is often unknown, it may be caused by obstruction of the tubes that carry sperm from the testicles^[4].

A spermatocele is not a sexually transmitted infection and is not contagious. If you have a spermatocele, you cannot give it to another person^[2].

Symptoms

A spermatocele usually causes no signs or symptoms and might remain stable in size^[1]. Smaller spermatoceles usually cause few or no symptoms. They may not bother you at all^[2].

Often a spermatocele does not cause symptoms. There may be an extra lump or mass above the testicle on one side of your scrotum, or you may notice enlargement of your scrotum^[4].

If the cyst becomes large enough, however, you might feel the following:

• Pain or discomfort in the affected testicle. This pain is typically dull and not severe but can be a source of ongoing discomfort^[1]
• Heaviness in the testicle with the spermatocele. A sensation of fullness or heaviness in the testicle can occur^[1]
• Fullness behind and above the testicle^[1]
• Swelling or redness of the scrotum^[4]
• Pressure at the base of the penis^[4]

Spermatoceles feel like a smooth, hard lump^[2]. Ejaculating will not make a spermatocele increase in size^[2].

When to see a doctor

Because a spermatocele usually doesn’t cause symptoms, you might discover it only during a testicular self-exam, or your doctor might find it during a routine physical exam^[1]. A healthcare provider typically detects a spermatocele during a routine physical examination or medical test for another issue. Some people discover a spermatocele while performing a testicular self-exam^[2].

It’s a good idea to have your doctor evaluate any scrotal mass to rule out a serious condition, such as testicular cancer. Also, call your doctor if you experience pain or swelling in your scrotum. A number of conditions can cause testicular pain, and some require immediate treatment^[1].

Even if there isn’t pain, it can be scary to notice a lump around your testicle. Talk to a healthcare provider if you notice changes to your testicles. Talking to a healthcare provider about any changes to your testicles is the first step in getting an official spermatocele diagnosis and soothing any frightening thoughts or feelings^[2].

How is it diagnosed?

To diagnose a spermatocele, you’ll need a physical exam. A spermatocele is usually diagnosed by examining the scrotum^[4]. Although a spermatocele generally isn’t painful, you might feel discomfort when your doctor examines the mass^[9].

You might also undergo the following diagnostic tests:

Transillumination: Your doctor might shine a light through your scrotum. With a spermatocele, the light will indicate that the mass is fluid-filled rather than solid. Spermatoceles are filled with fluid, so light will shine through them. Light will not pass through solid masses that may be caused by other problems, such as cancer of the testicle^[4].

Ultrasound: If transillumination doesn’t clearly indicate a cyst, an ultrasound can help determine what else it might be. This test uses high-frequency sound waves to create images of structures. It might be used to rule out a testicular tumor or other cause of scrotal swelling^[9]. An ultrasound may be used to confirm the diagnosis of a spermatocele^[4].

Treatment options

Although your spermatocele probably won’t go away on its own, most spermatoceles don’t need treatment. They generally don’t cause pain or complications^[9]. A spermatocele is not usually dangerous and is treated only if it grows larger or causes pain or other problems^[4].

Treatment is not usually needed if a spermatocele does not change in size or gets smaller as the body reabsorbs the fluid^[4]. If yours is painful, your doctor might recommend over-the-counter pain medications, such as acetaminophen or ibuprofen^[9]. Oral pain medications may be prescribed for symptomatic relief^[11].

Surgical treatment

If the spermatocele gets larger or causes discomfort, a procedure to remove the spermatocele, called a spermatocelectomy, may be needed^[4]. This procedure is generally performed on an outpatient basis, using a local or general anesthetic. The surgeon makes an incision in the scrotum and separates the spermatocele from the epididymis^[9].

After surgery, you might need to wear a gauze-filled athletic supporter to apply pressure to and protect the site of the incision. Your doctor might also tell you to:

• Apply ice packs for two or three days to keep swelling down
• Take oral pain medications for a day or two
• Return for a follow-up exam between one and three weeks after surgery^[9]

Possible complications from surgical removal that might affect fertility include damage to the epididymis or to the tube that transports sperm, called the vas deferens. It’s also possible that a spermatocele might come back, even after surgery, although this is uncommon^[9].

Sclerotherapy

Sclerotherapy is an alternative to surgical excision, but results appear to be less effective. This treatment is usually reserved for men who have no desire for future paternity because of the risk that the resulting chemical inflammation of the epididymis may impair fertility^[11].

Because aspiration (removal of fluid) of spermatocele alone is associated with a high recurrence rate, a sclerosing agent (a chemical substance) is used to cause the walls of the cyst to stick together. Various sclerosing materials have been used with varying success rates, including alcohol, doxycycline, and other agents^[11].

Impact on fertility

Having a spermatocele doesn’t affect fertility^[4]. They typically don’t reduce fertility or require treatment^[1]. Unlike some other conditions affecting the testicles, spermatoceles do not reduce fertility^[3].

Spermatoceles do not interfere with reproduction^[12]. They are not considered a cause of infertility by doctors. However, a large spermatocele may reduce the quantity and quality of sperm produced^[19].

What to expect

A spermatocele is unlikely to cause complications. Spermatoceles are benign, meaning they are not cancerous. They do not increase your risk of testicular cancer^[3].

However, if your spermatocele is painful or has grown so large that it’s causing you discomfort, you might need to have surgery to remove it^[22]. Most spermatoceles remain small and stable in size over time.

Observation is usually used for simple, small asymptomatic spermatoceles^[11]. Spermatoceles, sometimes called spermatic cysts, are common and typically don’t require treatment^[1].