Quick answer. Most testicular lumps and scrotal swellings are NOT cancer – common benign causes include epididymal cysts, hydroceles, varicoceles and infection (epididymo-orchitis). However, a PAINLESS lump in the testicle is the classic sign of testicular cancer, the commonest cancer in young men aged about 15-44 and highly curable when caught early (over 95% cure in early stages), so always get any new lump checked promptly and do regular self-checks. SUDDEN, severe testicle pain (often with swelling and nausea) may be testicular torsion – a surgical emergency where the testicle can be lost within hours, so go to A&E or call 995 immediately and do not wait. See a GP or urologist promptly for any lump, swelling or persistent dull ache.
Finding a lump or feeling pain in a testicle is alarming, but it helps to know that most scrotal lumps and swellings in Singapore turn out to be harmless – things like fluid-filled cysts, hydroceles, varicose-type veins, or treatable infections. That said, two situations always need urgent attention: a painless lump in the testicle, which is the classic warning sign of testicular cancer, and sudden, severe testicle pain, which can mean testicular torsion – a true emergency. This guide explains the common causes, the two red flags, how doctors assess the problem, and exactly when to see a GP or urologist versus when to head straight to A&E.
At a glance
| Cause | Typical features | What to do |
|---|---|---|
| Testicular cancer | Firm, usually painless lump within the testicle; change in size/firmness; sometimes dull ache or heaviness | See a GP or urologist promptly; ultrasound and blood tumour markers – highly curable when caught early |
| Testicular torsion | Sudden, severe one-sided pain, swelling, redness, often nausea/vomiting; more common in adolescents/young men | EMERGENCY – go to A&E or call 995 immediately; do not wait or use home remedies |
| Epididymo-orchitis (infection) | Pain and swelling building over 1-2 days, sometimes fever or burning on urination | See a doctor soon; usually treated with antibiotics, rest and pain relief |
| Epididymal cyst (spermatocele) | Smooth, painless, fluid-filled lump above/behind the testicle; very common | Get it confirmed by a doctor; usually harmless and left alone unless bothersome |
| Hydrocele | Soft, often painless swelling around the testicle from fluid build-up | See a doctor to confirm; harmless but can be treated with surgery if large or uncomfortable |
| Varicocele | Soft "bag of worms" feeling above the testicle, usually left-sided; may ache | See a doctor; treated if causing pain or fertility concerns |
Most lumps are benign – but always get them checked
The scrotum contains the testicles plus the epididymis (a coiled tube behind each testicle) and blood vessels, and several common, non-cancerous conditions can cause a lump or swelling:
- Epididymal cyst (spermatocele) – a smooth, fluid-filled lump above or behind the testicle. These are very common and are usually painless and harmless.
- Hydrocele – a collection of fluid around the testicle causing soft, often painless swelling of one side of the scrotum.
- Varicocele – enlarged veins above the testicle, classically described as feeling like a “bag of worms,” usually on the left side. Often harmless but occasionally linked to discomfort or fertility issues.
- Epididymo-orchitis – infection or inflammation of the epididymis and/or testicle, causing pain, swelling and sometimes fever (see below).
Even though these are benign, you cannot reliably tell them apart from cancer by feel alone. Any new lump, swelling or change deserves a prompt medical check.
Red flag 1 – a painless testicular lump: check for cancer
A firm, painless lump within the testicle itself is the classic sign of testicular cancer. While testicular cancer is uncommon overall (only about 1-2% of cancers in men), it is one of the most common cancers in young men – typically affecting those aged around 15-44, and in Singapore it ranks among the top cancers in men under 30. Other signs include a change in size or firmness of a testicle, a dull ache or heaviness in the scrotum or lower abdomen, or an unevenness compared with the other side.
The reassuring news: testicular cancer is one of the most treatable cancers. Caught early, cure rates exceed 95%, and even advanced disease is often curable. Because outcomes are so good when detected early, never ignore a painless lump or “wait and see” – see a doctor promptly.
Red flag 2 – sudden severe pain: a possible torsion emergency
Sudden, severe pain in one testicle is a medical emergency until proven otherwise. Testicular torsion happens when the spermatic cord twists and cuts off the testicle’s blood supply. It is most common in adolescents and young men (often ages 12-18), though it can happen at any age.
Warning signs include sudden, intense one-sided testicle pain (often setting in over minutes to a few hours), scrotal swelling and redness, and frequently nausea or vomiting. The pain may begin while sleeping. Time is critical: the testicle can usually be saved if surgery happens within about 6 hours, but the chance of saving it drops sharply with delay.
If you suspect torsion, go straight to A&E or call 995 immediately – do not wait, do not try home remedies, and do not massage the scrotum. If it is torsion, an emergency operation (untwisting and fixing the testicle in place) is needed as soon as possible.
Infection (epididymo-orchitis): pain, swelling and sometimes fever
Epididymo-orchitis is inflammation or infection of the epididymis and/or testicle. Unlike torsion, the pain and swelling usually build up more gradually over a day or two, and there may be fever, redness, or urinary symptoms (such as burning when passing urine). Causes include urinary or sexually transmitted infections.
This condition is treatable, usually with antibiotics, rest, scrotal support and pain relief – but it needs medical assessment. Importantly, because early torsion can sometimes mimic infection, sudden or severe pain should always be treated as a possible emergency rather than assumed to be infection.
How doctors assess a testicular lump or pain
Assessment is straightforward and usually quick:
- Examination – the doctor feels the testicle and scrotum to locate the lump, check whether it is within the testicle or separate from it, and assess tenderness.
- Scrotal ultrasound – a painless scan that is the key test for distinguishing solid lumps (which raise concern for cancer) from fluid-filled or vascular causes, and for assessing blood flow if torsion is suspected.
- Blood tumour markers – if cancer is suspected, blood tests for AFP, beta-hCG and LDH help with diagnosis and monitoring.
If cancer is confirmed, further imaging (such as CT) is used to check whether it has spread, and treatment is planned by a urologist and cancer team.
Be testicle-aware: how to do a self-check
Getting familiar with how your testicles normally feel makes it much easier to notice changes early. A simple monthly self-check takes a minute:
- Do it after a warm bath or shower, when the scrotal skin is relaxed.
- Examine one testicle at a time. Place your index and middle fingers underneath and your thumb on top, then gently roll the testicle between your fingers.
- Feel for any lumps, hard areas, swelling, or changes in size or firmness. It is normal for one testicle to be slightly larger or to hang lower, and for the soft epididymis behind each testicle to be felt.
See a doctor for any new lump, swelling, change in size or firmness, or a persistent dull ache or heaviness – and seek emergency care for sudden severe pain.
Related guides
- Best Urology Clinics in Singapore — our editorial shortlist
- urology clinics directory
- Low testosterone & andropause
- Premature ejaculation treatment
- Male infertility
Sources
- SingHealth – Testicular Cancer
- SingHealth – Testicular Torsion
- NUHS+ – Understanding Testicular Torsion
- HealthXchange (SingHealth) – Testicular Cancer: Higher Risk in Younger Men
- National University Cancer Institute, Singapore (NCIS) – Testicular Cancer
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