What testicular cancer looks like on the skin and in the testicle
Testicular cancer often shows up as a lump or swelling in one testicle, usually without pain. The lump may be small at first—sometimes the size of a pea—and can grow over weeks or months. You might notice the testicle feels heavier than usual, or one side of your scrotum (the pouch of skin holding the testicles) looks larger or hangs lower than the other.
The skin over the testicle may look normal, or it might appear slightly red or irritated. Some men describe a dull ache in the lower belly or groin, or a feeling of heaviness in the scrotum. These changes happen because the cancer is growing inside the testicle itself, not on the surface of the skin.
Not all lumps are cancer—many are benign (non-cancerous) cysts or other harmless growths. But any new lump, swelling, or change in how a testicle feels should be checked by a doctor. Early detection makes a real difference in treatment outcomes.
Key Takeaways
- A lump or swelling in one testicle, usually painless, is the most common first sign of testicular cancer.
- The affected testicle may feel heavier, look larger, or hang lower than the other one.
- Some men experience a dull ache in the groin or lower belly, or a feeling of heaviness in the scrotum.
- Any new lump or change in how a testicle feels should be examined by a doctor within a few weeks.
- Self-exams once a month can help you notice changes early, though most lumps turn out to be benign.
How to feel for changes during a self-exam
A testicular self-exam takes about three minutes and is best done after a warm shower, when the scrotum is relaxed. Hold your penis out of the way and examine one testicle at a time using both hands. Place your thumbs on top and your fingers underneath, then gently roll the testicle between your fingers and thumbs, feeling the entire surface.
You are looking for any lump, hard spot, or area that feels different from the rest of the testicle. It is normal to feel the epididymis—a cord-like structure at the back of each testicle that stores and carries sperm. Do not confuse this with a lump. Compare how each testicle feels; one is often slightly larger than the other, and that is normal.
If you find something that feels new or unusual, mark the date and check again in a week or two. If it is still there, or if it grows, contact your doctor. Many men find it helpful to do this exam on the same day each month, so they remember to do it regularly.
Other symptoms that may appear later
In early stages, testicular cancer may cause only a lump with no other signs. As the cancer grows, additional symptoms can develop. Some men notice swelling or tenderness in the breast tissue, a change that happens because certain types of testicular cancer produce hormones that affect the chest.
Back pain, belly pain, or shortness of breath can occur if the cancer has spread to lymph nodes or other organs, though these symptoms are less common at diagnosis. Fatigue, loss of appetite, or unexplained weight loss may also appear. These later symptoms do not mean the cancer is untreatable—they simply mean it has progressed and will need more intensive treatment.
If you have any of these symptoms along with a testicular lump, or if you have these symptoms without a lump you can identify, see a doctor. Many of these symptoms can have other causes, but they are worth investigating.
Why some lumps are not cancer
The testicles are prone to several benign conditions that create lumps or swelling. A hydrocele is a buildup of fluid around the testicle that makes the scrotum feel swollen and heavy but is not cancer. A varicocele is an enlargement of veins in the scrotum, sometimes described as feeling like a "bag of worms." Both are common and usually harmless.
Epididymitis is inflammation of the epididymis, often caused by infection, and causes pain and swelling that can mimic cancer. Testicular torsion is a twisting of the testicle that causes sudden, severe pain and requires emergency care, but is not cancer. Cysts and scar tissue can also create lumps that show up on self-exam.
The only way to know whether a lump is cancer is through medical testing. A doctor will perform a physical exam and usually order an ultrasound, which uses sound waves to create a picture of the inside of the testicle. This test can almost always tell the difference between cancer and benign conditions.
What happens after you notice a change
If you find a lump or notice swelling, contact your primary care doctor or a urologist (a doctor who specializes in the urinary and reproductive systems). Describe what you found, when you first noticed it, and whether it has changed. The doctor will examine both testicles and ask about pain, heaviness, or other symptoms.
If the doctor thinks further testing is needed, you will have an ultrasound. This is a painless imaging test that takes 10 to 15 minutes. The technician applies gel to your scrotum and moves a small handheld device over the area to create detailed images. The images show whether the lump is solid (more concerning for cancer) or filled with fluid (usually benign).
If the ultrasound suggests cancer, your doctor will refer you to a urologist or oncologist (a cancer specialist) for the next steps. If the ultrasound shows a benign condition, your doctor will explain what it is and whether any treatment is needed. Many benign lumps do not require treatment and can be monitored over time.
Risk factors and who is most likely to develop testicular cancer
Testicular cancer is rare overall, but certain factors increase the risk. Men between ages 15 and 40 are most commonly diagnosed, though it can occur at any age. A personal history of testicular cancer in one testicle raises the risk of cancer developing in the other testicle.
A family history of testicular cancer—meaning a father, brother, or son had it—increases risk. Men with a condition called cryptorchidism (an undescended testicle) have higher risk, even if the testicle was surgically moved into place. Infertility or difficulty fathering children is also associated with increased risk.
Race and ethnicity matter: testicular cancer is more common in white men than in men of other racial backgrounds. Having HIV also raises risk. Knowing your risk factors does not mean you will develop cancer, but it may prompt you to be more attentive to self-exams and to report any changes to your doctor promptly.
When to see a doctor about a testicular lump
You do not need to wait for a lump to grow or cause pain before seeing a doctor. Any new lump, swelling, or change in how a testicle feels warrants a medical evaluation within a few weeks. If you have sudden, severe pain in the testicle, seek care the same day or go to an emergency room, as this can indicate testicular torsion or another urgent condition.
If you have a family history of testicular cancer or other risk factors, discuss this with your doctor at your next routine visit. Your doctor can review whether self-exams make sense for you and what signs to watch for. If you are unsure whether something you feel is normal, it is better to have a doctor look at it than to worry in silence.
Frequently Asked Questions
Does testicular cancer always cause pain?
No. Many men with testicular cancer feel no pain at all—only a lump or swelling. Pain is not a reliable sign of cancer. Some benign conditions, like epididymitis or testicular torsion, cause severe pain, while some cancers cause none. Any new lump should be checked regardless of whether it hurts.
Can I tell the difference between a cancer lump and a benign one by feeling it?
Not reliably. A cancer lump is often hard and does not move around, but some benign lumps feel the same way. Only imaging tests like ultrasound can tell the difference with confidence. If you find a lump that feels new or unusual, see a doctor rather than trying to diagnose it yourself.
How fast does testicular cancer grow?
Growth speed varies. Some testicular cancers grow slowly over months, while others grow faster. This is one reason why checking yourself monthly and reporting changes to your doctor matters—catching a lump early, before it has time to spread, improves treatment outcomes significantly.
What if I find a lump but my doctor says it is nothing to worry about?
Your doctor may recommend monitoring the lump over time with follow-up exams or ultrasounds to make sure it does not change. Keep track of any changes and report them at your next visit. If the lump grows, becomes painful, or you develop new symptoms, contact your doctor again.
Is testicular cancer hereditary?
Testicular cancer can run in families, but it is not inherited in the straightforward way some other cancers are. Having a father or brother with testicular cancer raises your risk, but most men with a family history never develop it. If you have a family history, mention it to your doctor so you both know to stay alert.