Testicular Lumps or Swelling: Could It Be Cancer?
Most testicular lumps are not cancer. But all new lumps need investigation — because the ones that are cancer are highly curable when found early. A consultant sonographer explains the causes and what the scan looks for.
- Men's Health
- Updated July 2026
What Causes a Testicular Lump?
The majority of scrotal lumps are benign. The most common causes are:
| Cause | What It Is | Is It Serious? |
|---|---|---|
| Epididymal cyst / spermatocele | Benign fluid-filled cyst in the epididymis (the tube behind the testis) | No — benign, no treatment needed |
| Hydrocele | Fluid collection surrounding the testis | Usually no — may need urology review if large |
| Varicocele | Enlarged veins in the scrotum (like varicose veins) | Not dangerous, but may affect fertility |
| Epididymo-orchitis | Infection/inflammation of the epididymis and/or testis | Needs antibiotic treatment — see GP |
| Testicular torsion | Twisting of the spermatic cord — cuts off blood supply | Surgical emergency — A&E immediately |
| Testicular tumour | Solid mass within the testicular parenchyma | Yes — urgent urology referral needed |
| Inguinal hernia | Bowel or fat protruding through the inguinal canal into the scrotum | May need surgical repair |
The critical distinction that ultrasound makes is between an extratesticular lump (outside the testis — usually benign) and an intratesticular lump (inside the testis — requires urgent investigation). This distinction cannot be made reliably by clinical examination alone.
Signs That a Lump May Be Cancer
Testicular cancer typically presents as a painless, hard lump within the testis itself. The word "painless" is important — many men delay seeking assessment because they expect cancer to hurt. It often does not. Other signs include:
- A feeling of heaviness or dragging in the scrotum
- A dull ache in the lower abdomen, back, or groin
- A change in the size or firmness of one testis
- A sudden collection of fluid in the scrotum
- Breast tenderness (caused by hormones produced by some tumour types)
None of these symptoms confirm cancer — but all of them warrant a scrotal ultrasound within a few days. See: Testicular Cancer Screening: What You Need to Know
What to Do If You Find a Lump
Do not wait. Book a scrotal ultrasound or see your GP within a few days — not weeks. Most lumps are benign, and the scan will confirm this quickly. If the lump is a testicular tumour, early detection is the single most important factor in outcome: stage 1 testicular cancer has a five-year survival rate above 98%.
Exception: If you have sudden, severe testicular pain — the kind that comes on in minutes — go to A&E immediately. This may be testicular torsion, which is a surgical emergency requiring intervention within 4–6 hours.
To book a private scrotal ultrasound the same day: Book Testicular Ultrasound Scan — £235
From Our Practice
The most important thing we observe in men presenting with testicular lumps is the delay between finding the lump and seeking assessment. The average delay in our patient population is approximately three weeks. In the majority of cases, the lump turns out to be benign — an epididymal cyst or a hydrocele — and the three weeks of anxiety was unnecessary. In the smaller proportion of cases where the lump is a testicular tumour, the three-week delay is three weeks that the treatment pathway could have started sooner.
The message is simple: if you find a lump, get it scanned. The scan takes 20 minutes. The answer is the same day. The anxiety resolves immediately, one way or another.
Observations above are drawn from composite patterns across our patient population, not from any individual case.
Book a Testicular Ultrasound Scan
£235 · Same-day appointments · No GP referral needed · Verbal results in the room · Written report the same day
29 Weymouth Street, Marylebone, London W1G 7DB | 020 3633 4902
