Testicular lumps and swellings

The testicles are part of the male reproductive system. They produce sperm and testosterone (male sex hormone). The testicles sit inside a loose sac of skin, known as the scrotum, which hangs down behind the penis.

Testicular lumps and swellings can have many different causes. In rare cases, they can be a sign of testicular cancer. However, most lumps are benign (non-cancerous). Cancer Research UK estimates that less than four in every 100 testicular lumps are testicular cancer.

Types of testicular lumps and swellings

The four main types of testicular lumps and swellings are:

• varicocele, a swelling caused by dilated (enlarged) veins within the testicles
• hydrocele, a swelling caused by fluid around the testicle
• epididymal cyst, a lump caused by a collection of fluid in the epididymis (a long, coiled tube behind the testicles) - if it contains sperm, it is known as a spermatocele
• testicular torsion, a sudden painful type of swelling that occurs when a testicle becomes twisted, interrupting the blood supply to the testicles; it is a medical emergency (see below)

See Testicular lumps and swellings - causes for other types of testicular swellings.

How common are testicular lumps and swellings?

Varicoceles are relatively common, affecting about one in seven men. They usually become noticeable after puberty (when the body matures sexually) because by this time the testicles are fully grown and the blood flow to the affected veins increases.

Hydroceles affect 1 or 2 in every 100 newborn male babies. They can also occur in older boys or men after an injury or illness.

Epididymal cysts can develop at any age, but they are most common in middle-aged men and affect up to a third of men.

Testicular torsion usually develops in boys aged 13-17, but it can also occur in men who are in their 20s. It is a rare condition: figures from the US suggest that it affects 1 in every 4,000 males every year.

Outlook

Any lumps, swellings or changes to the testicles should always be checked by a healthcare professional.

Testicular torsion is a medical emergency and will require urgent surgery within hours of it starting.

Other types of lumps may not require any treatment because they often do not cause any symptoms. Hydroceles in newborn babies often disappear on their own during the first year or two.

If a lump causes pain or discomfort, it may be possible to have it surgically removed. See Testicular lumps and swellings - treatment for more information.

Epididymis

A long tube coiled tube behind the testicles that helps store and transport sperm.

Veins

Veins are a type of blood vessel that carry blood back to the heart.

Always visit your GP if you find a lump or swelling on one or both of your testicles.

In most cases, a lump or swelling is not cancerous, but you should always have it checked by a healthcare professional.

Varicoceles

In most cases, varicoceles do not cause any symptoms. However, up to 1 in 10 men may experience a heavy feeling or aching pain in either their:

• scrotum (the loose sac of skin that contains the testicles)
• groin

Varicoceles usually develop on the left side. This is due to the way that the veins in the testicles are arranged.

Varicoceles develop as a soft lump in the scrotum and can feel like a 'bag of worms'. The size of varicoceles can vary. Some may only be noticeable when you touch them. Others can be larger and seen easily. The side of the scrotum that contains the varicoceles may hang slightly lower than the other side.

Varicoceles may be linked to infertility. However, about two out of three men with varicoceles can have children. There is no evidence that surgically removing varicoceles improves fertility.

Hydroceles

Hydroceles usually affect newborn babies. In almost all cases the only symptom is a painless swelling of one or both testicles. Hydroceles can sometimes affect older boys or men, who may feel pressure in their abdomen (tummy).

Epididymal cysts

Epididymal cysts develop as a small, smooth fluid-filled lump. Removing fluid from inside the cyst by squeezing it is not recommended because it can lead to scarring or infection.

Epididymal cysts do not usually cause symptoms unless they become infected. Symptoms of infection can include:

• a red, swollen and painful cyst
• a foul-smelling yellow fluid that drains from the cyst

Testicular torsion

Unlike the other types of benign (non-cancerous) testicular lumps, testicular torsion is a medical emergency.

Dial 999 for an ambulance if you suspect that you or someone you know has testicular torsion.

In cases of testicular torsion, surgery needs to be carried out as soon as possible to avoid the loss of the testicle.

The symptoms of testicular torsion usually begin with a severe pain in one of your testicles. Other possible symptoms include:

• swelling of the scrotum
• nausea (feeling sick)
• vomiting
• abdominal (tummy) pain
• a high temperature (fever) of 38ºC (100.4ºF) or more
• a frequent need to urinate

Some people with testicular torsion may have had episodes of testicular pain and swelling in the past.

There are many different causes of testicular lumps and swellings. Testicular cancer is a possible cause. About 2,000 cases of testicular cancer are diagnosed in the UK every year. However, less than 4 in 100 lumps are testicular cancer.

The main types of lumps and their causes are explained below.

Varicoceles

The exact cause of varicoceles is unknown. However, most experts believe that they are caused by abnormalities in the veins in the testicles. There may be a blockage in the veins, or a problem with the valves in the veins. The valves are flaps that prevent blood flowing in the wrong direction.

The abnormal veins do not circulate blood as efficiently as normal veins. This leads to a build-up of excess blood in the veins, which makes them swell.

During puberty (when the body matures sexually), blood flow increases to the testicles and they grow larger. This can make varicoceles more noticeable.

Hydroceles

During pregnancy, a male baby's testicles develop inside his abdomen (tummy). Once they have formed, the testicles pass down through a passage and into the scrotum (the loose sac of skin that contains the testicles).

Usually, the passage closes before birth but, in some cases, it stays open. If the passage remains open, fluid can pass from the abdomen into the scrotum, causing the swelling that is associated with a hydrocele.

In most cases, the fluid is absorbed into the surrounding tissue during the child's first year or two of life, and the hydrocele disappears.

Hydroceles that develop in men or older boys may be indicated by inflammation (redness and swelling) of the scrotum, which is caused by:

• an injury
• an infection
• a tumour (growth)

Epididymal cysts

The epididymis is a coil-like structure behind the testicles that helps to store and transport sperm. Sometimes, a fluid-filled swelling can appear on the epididymis, although the cause is usually unknown.

People who have certain conditions that affect their kidneys may be at increased risk of developing epididymal cysts. For example, autosomal dominant polycystic kidney disease (ADPKD) is a genetic condition that causes multiple cysts to develop on the kidneys.

Testicular torsion

The testicles hang from a cord known as the spermatic cord. The spermatic cord should be loose enough to allow the testicles some movement within the scrotum but not so loose that they can move too freely.

Some boys are born with a spermatic cord that is too loose. This means that there is an increased risk of a testicle moving too much and twisting the spermatic cord as a result.

If a spermatic cord becomes severely twisted, the main blood supply for the affected testicle can be interrupted. This is a dangerous situation. If not treated immediately, the testicle may die. Immediate surgery is needed to untwist the cord, restore the blood supply and save the testicle.

Testicular torsion is most common among boys aged 13-17, although it can also occur in:

• men in their 20s
• unborn babies in the womb
• newborn babies

Testicular torsion can sometimes occur if there is trauma to the testicle, such as in an accident. However, most cases happen for no apparent reason. Testicular torsion may be more likely if you have:

• a tumour (growth) in your testicles
• a history of undescended testicles (where a boy is born without one or both testicles in their scrotum)

Other causes

Other causes of testicular lumps or swellings include:

• epididymitis - inflammation of the epididymis, which may be caused by a sexually transmitted infection or a urinary tract infection
• epididymo-orchitis - epididymitis (see above) combined with orchitis (inflammation of the testicle), which is usually due to an infection
• an inguinal hernia - a piece of your bowel pokes through a weakness in the muscle or surrounding tissue wall into your groin; more than a quarter of men will have an inguinal hernia during their lifetime

Cyst

A cyst is a fluid-filled sac or cavity in the body.

Epididymis

A long tube coiled tube behind the testicles that helps store and transport sperm.

Genetic

Genetic is a term that refers to genes. Genes are the characteristics inherited from a family member.

Inflammation

Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Always visit your GP if you notice any lumps or swellings in your testicles. In very rare cases, a lump can be a sign of testicular cancer (less than 4 in 100 lumps).

Your GP will ask you whether you have:

• felt any pain - and if so, where it was, how severe it was and how long it lasted for
• any other symptoms, such as pain when you urinate (which is a sign of a urinary tract infection) or any discharge from your urethra (the tube that carries urine from the bladder to outside of the body)
• a history of trauma, such as a sports injury to your groin

Your GP will also physically examine your testicles to check:

• the size of your testicles
• the position of the lump or swelling
• whether the lump causes any pain when it is touched
• whether the lump is firm or soft

If your GP cannot confirm a diagnosis from the examination alone, you may need to have an ultrasound scan. This uses high-frequency sound waves to create an image of the inside of your body.

Varicoceles

A varicocele can usually be diagnosed by your GP asking about your symptoms and carrying out a physical examination. Further testing is not usually necessary.

Referral

In some cases, you may be referred to a urologist (a doctor who specialises in treating conditions that affect the urinary system). For example, if:

• a varicocele suddenly develops
• you have a single varicocele on the right side
• there is uncertainty about the cause of your lump
• you are in pain
• it is causing you embarrassment

In these circumstances, you may be referred for an ultrasound scan to confirm the diagnosis and check for any problems.

Hydroceles

As with varicoceles, a hydrocele can usually be diagnosed through a physical examination.

If a hydrocele develops in your child, your GP will feel your child's scrotum (the loose sac of skin that contains the testicles) to check that the swelling is caused by fluid and not something solid. The fluid is usually clear, so your GP may shine a torch through the scrotum. If a hydrocele is present, the outlines of the testicles should appear against the background of the fluid.

If you have a hydrocele, your GP will examine your scrotum as described above. If you are 20 to 40 years old, your GP may refer you for an ultrasound scan to rule out testicular cancer.

If your GP suspects that your hydrocele may be caused by an infection, they may ask for a urine sample and test it. Alternatively, your GP may use a swab (small piece of absorbent material, such as gauze, attached to the end of a stick) to collect a sample of cells and fluid from your urethra. This sample can then be tested to see if you have an infection.

Epididymal cysts

An epididymal cyst can usually be diagnosed through a physical examination. Further tests are not usually required.

Testicular torsion

Testicular torsion is usually diagnosed by the distinctive symptoms of severe testicular pain and swelling.

The diagnosis can be confirmed by using an ultrasound scan or a magnetic resonance imaging (MRI) scan. This uses a strong magnetic field and radio waves to produce detailed pictures of the inside of your body. However, these tests may delay the urgent surgical treatment and so are often not carried out.

Groin

The area at the front of the body where the thighs meet the tummy.

Urethra

The urethra is a tube that carries urine from the bladder to the outside of the body.

Treatment for your testicular lump will depend on the underlying cause of the lump.

Varicoceles

In most cases, varicoceles do not require any treatment. If you have a varicocele and you are in pain or discomfort, you can:

• take painkillers, such as paracetamol
• wear tight-fitting, supportive underwear

If your varicocele is still causing you pain or discomfort, surgery may be recommended.

Surgery

A surgical technique called varicocele embolisation can be used to treat varicoceles. You will usually be referred to a urologist (a doctor who specialises in treating conditions that affect the urinary system) to discuss the benefits and risks of surgery.

A varicocele embolisation is usually carried out on an outpatient basis, which means that you will not have to stay in hospital overnight. It is usually carried out under local anaesthetic (painkilling medication to numb the affected area).

Your surgeon will use X-ray equipment to guide a tiny tube into the affected veins in your testicles. They will use metal coils or a special liquid to block the veins. The blood will then bypass the blocked veins, reducing the swelling and removing the varicocele.

Varicocele embolisation is a very safe procedure, although there is a small risk of infection. If infection occurs, it can be treated with antibiotics (medication to treat bacterial infections). Other possible risks include:

• the varicocele returning
• numbness or pain in the scrotum (loose sac of skin that contains the testicles)

Some varicoceles require a different treatment in the form of surgery to directly divide the dilated (widened) veins. This is usually performed under general anaesthetic so you will be unconscious. Your surgeon will make an incision in your groin, then find and remove the dilated veins.

More than 9 out of 10 varicoceles are successfully removed through surgery.

Hydroceles

Hydroceles in newborn babies usually disappear on their own within the first year or two of life. Treatment for hydroceles is usually only needed if they persist for longer than this or if they cause troublesome symptoms. Hydroceles in older boys and men may be treated if they are causing pain or discomfort.

Surgery

If you need treatment for hydroceles, a surgical procedure known as a hydrocelectomy may be recommended.

A hydrocelectomy is carried out under general anaesthetic. The surgeon will make an incision in the scrotum to drain away the fluid before sealing the passageway between the abdomen (tummy) and the scrotum. The incision is closed using dissolvable stitches. Most people will be able to return home soon after having the operation.

As with a varicocele embolisation, there is a small risk of infection after a hydrocelectomy. Children may be given antibiotics before or during the operation to prevent infection.

Epididymal cysts

Epididymal cysts do not usually require any treatment. However, if they are causing troublesome symptoms, you may be referred to a urologist.

Your urologist may recommend further treatment, or may suggest surgically removing the entire cyst under local anaesthetic. This may leave some scarring.

Testicular torsion

If you have testicular torsion, you will need to have surgery as soon as possible to release the trapped testicle. Permanent injury to the testicle can occur within four hours of having testicular torsion, which may affect your fertility or result in the loss of your testicle.

Surgery for testicular torsion is carried out under general anaesthetic. The surgeon will make a cut in your scrotum before untwisting the spermatic cord (the cord that the testicles hang from inside the scrotum). The testicle (or testicles) will then be stitched to the inside of the scrotum to prevent the spermatic cord twisting again.

The longer you wait before having surgery, the higher the risk that your surgeon will not be able to save the trapped testicle. Figures show that when people have surgery within six hours of testicular torsion occurring, 9 out of 10 trapped testicles will be saved. However, if the surgery is delayed for 24 hours, only 1 out of 10 trapped testicles will be saved.

Following surgery for testicular torsion, you may need to avoid strenuous activity for about a week. Your surgeon will be able to advise you about this.

Other types of lumps

Other types of lumps are treated differently depending on their cause. For example, if your lump is caused by an underlying infection, the infection may be treated with antibiotics. See the Health A-Z topics about Sexually transmitted infections and Urinary tract infections if one of these has caused your lump.

If you have been diagnosed with testicular cancer, it may be treated with surgery and radiotherapy. See the Health A-Z topic about Testicular cancer - treatment for more information.

If you have been diagnosed with an inguinal hernia, you will usually need to have an operation. See the Health A-Z topic about Inguinal hernia repair for more information.

Groin

The area at the front of the body where the thighs meet the tummy.