Nottingham Urology Group Logo

Testicular swellings - What are they?

Swellings in the scrotum are quite common and most of them are not serious. However if you do discover a lump then you should seek the advice of a doctor who will be able to advise whether further tests are needed. Common types of lumps include:

  • Swellings in the scrotal skin
  • Large hernias
  • Hydrocele (fluid around the testicle)
  • Epididymal cyst
  • Infections of the testis or epididymis
  • Testis cancer

Swellings in the scrotal skin

Nodules can grow in the skin of the scrotum. These are usually called sebaceous cysts and originate from blocked skin glands. Typically they form swellings 1-2 cms in diameter. Occasionally they can discharge white toothpaste like material. They can also get infected so that you get a small abscess in the skin.

Some patients seem to get quite large numbers of these cysts.

If treatment is required, then the cysts can be removed with a straight forward minor operation done under local anaesthesia.


Hernias originate in the groin and sometimes if they enlarge they protrude down into the scrotum. Sometimes these swellings can be very large indeed. They are best treated by an operation performed by a specialist hernia surgeon, who will often be able to perform the procedure by a keyhole technique.


A hydrocele is a collection of fluid around the testis. We don’t understand in most patients why the fluid begins to collect but once it begins slowly over the months or years, the swelling increases in size and some can be very large – perhaps 15 cms diameter. Once they have started to form they do not go away. Occasionally the hydrocele fluid is triggered by an infection and if this is the case, then the fluid will disperse.

Hydroceles are not dangerous but give trouble because they are uncomfortable and get in the way.

Epididymal cysts

These are sometimes called spermatoceles and originate from the sperm sac adjacent to the testis which is called the epididymis. We do not know why they form. Again, once they start they very rarely disperse and can grow to 6-7 cms diameter. They are not harmful but give some discomfort and are a nuisance with activity and bending.

Infections of the testicles

Infection of the testis and sperm sac is called epididymal orchitis. It is a painful infection often associated with a fever and alteration of the way you pass urine as the germs may have spread from the bladder into the testis.

In patients below the age of 35 the commonest organism is usually sexually transmitted, particularly Chlamydia. Your doctor will probably recommend that you are seen in the Genito Urinary Medicine Department for necessary tests and investigation of your partners. Infection will resolve with antibiotics.

In older men, infection is usually with a germ called E.Coli which is the commonest organism to give urine infections. This is usually a more severe infection than Chlamydia quite often with a lot of swelling and redness of the skin. Sometimes abscesses can form and patients require admission to hospital and sometimes surgical intervention to drain any abscesses. Recovery is usually complete with antibiotics but it may take many weeks for the swelling to resolve.

Testicle cancer

Testicular cancer is not common, but it is important to get things checked if you find any lumps or bumps in the testicle. Testicle cancer usually affects young men (eg 15-45 years old) but can affect men of other ages too. The symptoms and signs of testicle cancer include:

  • a hard lump in the testicle itself, which feels attached or part of the testicle
  • a sudden increase or decrease in the size of the testicle
  • testicle pain is not a common symptom