Scrotal Lumps

The key causes of scrotal or testicular lumps are:

  • Hydrocele
  • Varicocele
  • Epididymal cyst
  • Testicular cancer
  • Epididymo-orchitis
  • Inguinal hernia
  • Testicular torsion

 

Hydrocele

A hydrocele is a collection of fluid within the tunica vaginalis that surrounds the testes. They are usually painless and present with a soft scrotal swelling. The tunica vaginalis is a sealed pouch of membrane that surrounds the testes. Originally the tunica vaginalis is part of the peritoneal membrane. During the development of the fetus, it becomes separated from the peritoneal membrane and remains in the scrotum, partially covering each testicle.

Examination findings with a hydrocele are:

  • The testicle is palpable within the hydrocele
  • Soft, fluctuant and may be large
  • Irreducible and has no bowel sounds (distinguishing it from a hernia)
  • Transilluminated by shining torch through the skin, into the fluid (the testicle floats within the fluid)

 

Hydroceles can be idiopathic, with no apparent cause, or secondary to:

  • Testicular cancer
  • Testicular torsion
  • Epididymo-orchitis
  • Trauma

 

Management involves excluding serious causes (e.g., cancer). Idiopathic hydroceles may be managed conservatively. Surgery, aspiration or sclerotherapy may be required in large or symptomatic cases.

 

Varicocele

A varicocele occurs where the veins in the pampiniform plexus become swollen. They are common, affecting around 15% of men. They can cause impaired fertility, probably due to disrupting the temperature in the affected testicle. They may result in testicular atrophy, reducing the size and function of the testicle.

The pampiniform plexus is a venous plexus, which is found in the spermatic cord and drains the testes. The pampiniform plexus drains into the testicular vein. It plays a role in regulating the temperature of blood entering the testes by absorbing heat from the nearby testicular artery. The testicles need to be at an optimum temperature for producing sperm.

Varicoceles are the result of increased resistance in the testicular vein. Incompetent valves in the testicular vein allow blood to flow back from the testicular vein into the pampiniform plexus.

The right testicular vein drains directly into the inferior vena cava. The left testicular vein drains into the left renal vein. Most varicoceles (90%) occur on the left due to increased resistance in the left testicular vein. A left-sided varicocele can indicate an obstruction of the left testicular vein caused by a renal cell carcinoma.

Varicoceles may present with:

  • Throbbing/dull pain or discomfort, worse on standing
  • A dragging sensation
  • Sub-fertility or infertility

 

Examination findings are:

  • A scrotal mass that feels like a “bag of worms”
  • More prominent on standing
  • Disappears when lying down
  • Asymmetry in testicular size if the varicocele has affected the growth of the testicle

 

Varicoceles that do not disappear when lying down raise concerns about retroperitoneal tumours obstructing the drainage of the renal vein. These warrant an urgent referral to urology for further investigation.

Investigations to consider are:

  • Ultrasound with Doppler imaging can be used to confirm the diagnosis
  • Semen analysis if there are concerns about fertility
  • Hormonal tests (e.g., FSH and testosterone) if there are concerns about function

 

Uncomplicated cases can be managed conservatively. 

Surgery or endovascular embolisation may be indicated for pain, testicular atrophy or infertility.

 

Epididymal Cysts

Epididymal cysts occur at the head of the epididymis (at the top of the testicle). A cyst is a fluid-filled sac. An epididymal cyst that contains sperm is called a spermatocele. Management of epididymal cysts and spermatoceles is identical.

Epididymal cysts are very common in adults, occurring in around 30% of men. Most cases are asymptomatic. Patients may present having felt a lump, or they may be found incidentally on ultrasound for another indication.

Examination findings are:

  • Soft, round lump 
  • Typically at the top of the testicle
  • Associated with the epididymis
  • Separate from the testicle
  • May be able to transilluminate large cysts (appearing separate from the testicle)

 

Usually, they are entirely harmless and are not associated with infertility or cancer. Occasionally, they may cause pain or discomfort, and removal may be considered. Exceptionally rarely, there may be torsion of the cyst, causing acute pain and swelling.

 

Last updated May 2021