Aetiology
A good way to approach the differentials of scrotal lump / swelling is by determining if there is pain or not.
Causes of Painless Scrotal Lump / Swelling
The following causes are most commonly completely painless, or occasionally associated with a dull ache or heaviness if the mass / swelling is significant.
Important causes:
| Feature | Testicular tumour | Epididymal cyst | Hydrocele | Varicocele | Inguinal hernia (into the scrotum) |
|---|---|---|---|---|---|
| Transillumination | No | Yes (hydrocele > epididymal cyst) | No | ||
| Ability to “get above” lump | Yes | No (extends above into the inguinal canal) | |||
| Key features |
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May be painful if incarcerated / strangulated |
Less common causes of painless scrotal lump / swelling:
| Cause | Description | Clinical features |
|---|---|---|
| Haematocele | A hydrocele filled with blood |
|
| Spermatocele | An epididymal cyst that contains spermatozoa (on histology) |
|
| Squamous cell carcinoma of the scrotum | Extremely rare |
|
Causes of Painful Scrotal Lump / Swelling
There are 2 important causes of painful scrotal lump / swelling:
| Feature | Testicular torsion | Epididymo-orchitis |
|---|---|---|
| Typical age | Teenagers & young men (12–25 yrs) | Sexually active adults or older men |
| Onset | Sudden onset | Gradual onset over hours to days |
| Clinical features |
|
|
| Position of the testis | High-riding testis (affected testis appears elevated) | Normal |
| Cremasteric reflex | Absent | Present |
| Prehn’s sign (pain relief on testis elevation) | Negative – pain not relieved | Positive – pain often improves |
See the Testicular Torsion and Epididymo-Orchitis articles for more information.
The following causes can also be painful (although covered in the painless section above):
- Incarcerated / strangulated inguinal hernia
- Haematocele
Investigations
Testicular torsion should be suspected and excluded in any patient presenting with acute scrotal pain and/or swelling, before considering any other causes
1st line investigation for scrotal swelling: ultrasound
| Indications for urgent ultrasound (outpatient basis) | ANY of the following, provided the swelling is NOT of acute onset:
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| Do not arrange an ultrasound if |
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Management
Management depends on the underlying cause, see the corresponding articles: