Testicular cancer is one of the most curable forms of cancer, particularly when it is diagnosed early. It involves uncontrolled cell growth in the testes — the male sex organs that make and store sperm and produce testosterone. While testicular cancer is generally rare, it is the most common form of cancer in young men, most often appearing between the ages of 15 and 44.
Found a lump, or noticed a change? See your GP without delay — they will examine you and, where appropriate, refer you for an ultrasound. We provide the Scrotal / Testes Ultrasound Scan at our three Dublin clinics, 7 days a week, with a consultant radiologist's report sent to your GP.
Risk Factors and Types
The exact cause of testicular cancer remains unknown, though certain factors show correlation:
- An undescended testicle (cryptorchidism)
- Klinefelter syndrome
- Genetic factors and family history
Importantly, many men diagnosed with testicular cancer have no risk factors at all — which is why awareness of the signs matters for everyone.
Most cases originate in germ cells (the cells that produce sperm) and are classified as:
- Seminomas — develop and spread more slowly, and usually respond very well to treatment
- Non-seminomas — faster-growing, with several different subtypes
Cancers can also arise in other cell types (such as Sertoli–Leydig cell tumours), but these are much less common.
Early Signs and Symptoms to Watch For
Enlargement of a testicle, or a small hard lump on the testicle, is typically the first sign. When a tumour is detected early it may be only the size of a pea — but left unchecked it can grow much larger. Watch for:
- A lump or swelling in either testicle — painful or not, it should be checked
- A change in the size, firmness, or texture of either testicle
- A feeling of heaviness or weightiness in the scrotum
- Pressure or a dull ache in the groin or lower abdomen
- Pain, tenderness, or discomfort in a testicle or the scrotum
- Breast tenderness or enlargement (rare — some testicular tumours produce hormones)
One testicle being slightly larger than the other is normal. What matters is change — in size, shape, or feel.
Signs of later-stage disease
If cancer spreads before it is found, symptoms can include lower back pain, chest pain, breathing difficulty, coughing (sometimes with blood), or swelling from blood clots. These symptoms make prompt review even more important — but remember they can all have other causes too.
How to Do a Testicular Self-Exam
Doctors recommend that men aged roughly 15–55 examine themselves once a month. The best time is during or after a warm shower or bath, when the scrotal skin is relaxed:
- Support the scrotum in the palm of one hand and note the size and weight of each testicle.
- Roll each testicle gently between your thumb and fingers, one at a time, feeling the whole surface. It should feel smooth, firm, and slightly spongy — without hard lumps.
- Find the epididymis — the soft, rope-like structure along the back of each testicle. Learn how it normally feels so you don't mistake it for a lump.
- Compare sides. A small difference in size is normal; a new difference, or a change since last month, is not.
If you notice a lump, swelling, hardness, or any change, make an appointment with your GP promptly. Most changes turn out to be benign — but the only way to know is to have it examined.
Conditions That May Be Mistaken for Cancer
Several benign conditions can mimic the symptoms of testicular cancer:
- Varicocele — an enlargement of the veins surrounding the testicle
- Hydrocele — a build-up of fluid in the membrane around the testicle
- Hernia — a tear in the abdominal muscle above the groin
- Epididymal cyst (spermatocele) — perhaps the condition most commonly mistaken for a tumour: a benign, fluid-filled lump that develops on the epididymis, felt as a smooth, firm lump near the top of the testicle. Epididymal cysts are harmless and usually need no treatment, though they can be removed if painful or growing.
- Infection or injury — epididymitis and groin injuries can cause pain and swelling too
Your GP can often distinguish these on examination, and an ultrasound scan can confirm what a lump actually is.
How Testicular Cancer Is Diagnosed
If your GP suspects anything, they will typically:
- Order blood tests for tumour markers — alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG)
- Refer you for imaging — a scrotal ultrasound is the standard first test for characterising testicular lumps
If tests confirm cancer, surgery to remove the affected testicle is almost always the first treatment step; it also tells the oncologist exactly which type of cancer is present so the right follow-up treatment can be planned. Caught early, treatment success rates are excellent.
Frequently Asked Questions
Is a testicular lump always cancer?
No — most testicular lumps are benign (epididymal cysts, hydroceles, and varicoceles are all common). But there is no way to tell by feel alone, so every new lump should be checked by your GP.
How often should I check my testicles?
Once a month, ideally during or after a warm shower. The goal is to know your own normal so you notice change early.
Is testicular cancer painful?
Often not — many tumours are painless at first, which is exactly why a painless lump still needs review. Some men do notice an ache or heaviness.
What will the GP do about a testicular lump?
They'll examine you, may organise blood tests, and will usually refer you for a scrotal ultrasound to characterise the lump. If an ultrasound is recommended, we scan 7 days a week at three Dublin clinics with a consultant radiologist's report sent to your GP.
If you're concerned about any symptoms, speak to your GP first. If an ultrasound is recommended, we provide the Scrotal/Testes Ultrasound Scan at Ultrasound Ireland — call 01 210 0232.
This article is for general information only and is not medical advice. It is not a substitute for professional diagnosis or treatment — always speak to your GP or another qualified healthcare provider about your own situation.
