What every man should know about his testicles

Recently, a boy came into my clinic accompanied by his girlfriend. He had felt something strange in his testicle months before. She found out and dragged him to consult me.

I did a physical exam and confirmed what I felt with an ultrasound. The lump turned out to be a benign cyst, not cancer.

He leaned over to her and said, "See? I told you. I'm fine." I told him that he should thank her instead, as this visit could have had a very different outcome.

Most testicular lumps are not cancerous, but some are. And the only way to know is to see a doctor. When a man waits, he puts off treatment - often for something a doctor could diagnose in minutes. Or a doctor could find something that could save your life.

During my urology internship in medical school, I examined my own testicles for the first time. I found something, got scared and made an appointment. Like my recent patient, I discovered I had a benign cyst - almost certainly present my entire life. I simply never knew what "normal" felt like before that defining moment.

For this reason, I recommend that patients get into the habit of doing regular self-examinations. There's no need to obsess, and there are no formal guidelines that require monthly checks. But familiarizing yourself with your normal anatomy - checking it periodically while you shower - helps you recognize changes when they happen. The entire exam takes less than two minutes.

The more you know your baseline, the easier it is to notice when something is wrong.

The testicles have two main functions
The main function of the testicles is to produce sperm. A healthy man produces tens of millions of sperm every day. These sperm can take about three months to grow, mature and be released into the ejaculate.

The second essential function of the testicles is to produce male sex hormones - mainly testosterone. Specialized cells called Leydig cells produce most of the testosterone in a man's body. Testosterone is responsible for muscle mass, bone density, libido, mood and energy - all essential factors for the functioning of the male body.

The ideal is to have two testicles, but men can live a normal life with just one. A man can live a full life, including having children, with a single testicle.

The testicles don't start where they end
While the male fetus develops in the uterus, the testicles originate in the abdomen, near the kidneys. In the last months of pregnancy, the testicles descend through a channel called the inguinal canal until they reach the scrotum, the sac that protects them for the rest of the man's life.

This descent is the reason why the testicles hang outside the body and why testicular pain can radiate to the abdomen. Sperm production works best at a temperature slightly lower than core body temperature.

The scrotum is a temperature-controlled chamber that adjusts automatically - pulling the testicles closer to the body when it's cold and lowering them when it's hot. That's why everything feels different in a cold pool compared to a hot shower.

What exactly is down there?
The scrotum usually contains two testicles. Each is a smooth, firm, oval organ about the size of a small egg. Internally, the testicle is full of small compacted tubules called seminiferous tubules, where sperm are produced.

At the back of each testicle is a soft, worm-like structure called the epididymis, where sperm mature. From there, sperm travel through the vas deferens, a long tube that runs from the scrotum toward the bottom of the pelvis to enter the ejaculatory ducts. This vas deferens is the same tube that is cut during a vasectomy.

Everything that keeps the testicle alive and functional passes through the spermatic cord - arteries, veins, nerves and lymphatic vessels, grouped together with the vas deferens. You can feel cord structures emerging from the top of each testicle. The cord is surrounded by muscles that help move the testicle.

What is normal?
One of the testicles is usually a little lower than the other, usually the left one. One of them is slightly larger than the other and can be on either side. What is that soft, lumpy, worm-like structure at the top and back of each testicle? It's the epididymis, not a tumor. A cord-like structure that extends from the top of each testicle is the spermatic cord. Cysts can form in the testicle or epididymis, but are usually benign.

You may notice enlarged veins above the testicle, which look like a small bag of worms. This could be a varicocele - a common and usually harmless condition - but it's worth seeing a doctor if it's new and painful, or if you have fertility concerns.

Tesicles moving up and down depending on temperature, exercise, or arousal are also normal.

What's not normal
A firm, painless lump in the testicle itself is a warning sign. It is the classic presentation of testicular cancer. About 9,800 men in the United States will be diagnosed with testicular cancer in 2026, according to the American Cancer Society. The disease is most common in young and middle-aged men, especially those in their 20s and 30s, and is one of the most treatable cancers when detected early - survival is around 99% when the cancer is diagnosed at an early stage.

If you find a firm lump, you should see a doctor immediately, even if you feel well. Most testicular cancers are painless, but pain does not rule out the possibility of cancer. A physical exam, ultrasound and/or laboratory tests can help differentiate a benign tumor from cancer.

Cyclist Lance Armstrong's diagnosis of testicular cancer in 1996 made it a familiar subject. Earlier this year, Dwayne "The Rock" Johnson experienced a similar scare. Her lump was painful and turned out to be epididymitis, or inflammation of the epididymis, not cancer.

Painful swelling, redness or warmth - sometimes accompanied by painful or frequent urination or fever - can be symptoms of epididymitis, the condition Johnson had. It is treatable, usually with antibiotics, anti-inflammatories and rest.

Sudden, intense pain in one of the testicles may be a sign of testicular torsion - the spermatic cord twists on itself, interrupting blood flow. Testicular torsion is a medical emergency, period. If the testicle is not untwisted within a few hours, it may be lost.

What happens at a doctor's appointment?
Your consultation with the urologist will begin with a conversation about when you noticed something strange, how you feel, whether there is pain or urinary symptoms, and your relevant medical history. During the physical exam, the doctor will examine the scrotum, testicles, epididymis, and spermatic cord. The doctor checks the same things you would check at home, only with more experience.

From there, the investigation depends on what the doctor finds. The urologist may order a scrotal ultrasound to obtain a clearer image of the testicle and surrounding structures. It's the same basic exam that Johnson described having done after the scare.

Doctors may order urine tests if they suspect infection, blood tests for tumor markers if cancer is suspected, or hormone tests if testosterone is involved in the investigation. Occasionally, urologists may order an MRI scan for a more detailed analysis of the internal anatomy of the testicle.

How to self-assess yourself
I recommend that patients do a self-examination in the shower. The warm water relaxes the scrotum, which makes it easier to palpate the testicles.

Take a few minutes to examine one testicle at a time. Gently roll it between your thumb and fingers. Don't press. Feel the shape, size and surface.

Locate the epididymis at the back. Note the spermatic cord rising.

Remember: If you find something new - a lump, a hardened area, a change in size, persistent pain - during a self-exam, don't delay and don't put off seeing your doctor. Seek assistance as soon as possible. Prevention is the best way to take care of your health.

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Source: CNN