Understanding Testicular Cancer
Testicular cancer develops in one or, less often, both testicles. These walnut-shaped organs sit inside the scrotum, a loose bag of skin underneath the penis. The testicles have two main jobs: making sperm and producing the hormone testosterone, which is responsible for male characteristics and sex drive.[1]
This type of cancer is not very common compared to other cancers. However, it stands out because it mostly affects younger men, particularly those between ages 15 and 45. This makes it quite different from many other cancers that tend to develop later in life. Despite its rarity, testicular cancer is the most common cancer in men aged 20 to 35.[2][4]
The good news is that testicular cancer is highly treatable. Even when it has spread to other parts of the body, the chances of successful treatment remain very high. With modern treatments, cure rates can reach over 90%, and the five-year survival rate exceeds 95%. This means that most men diagnosed with testicular cancer go on to live long, healthy lives.[3]
How Common Is Testicular Cancer?
Testicular cancer is considered rare. It affects only about 1 in 250 people with testicles. It represents just 1% of all male cancers and about 5% of urological cancers, which are cancers affecting the urinary system and male reproductive organs.[2][3]
Even though it’s uncommon overall, testicular cancer is the leading cancer diagnosis among young men in their teens, twenties, and early thirties. This age group is typically healthy and active, which can make the diagnosis particularly shocking. The incidence of testicular cancer has been increasing over recent decades. Studies show that cases have doubled over the past 40 years, though researchers are still working to understand exactly why this is happening.[3]
Testicular cancer also shows differences across racial and ethnic groups. It is more common among non-Hispanic white men in the United States and Europe, and less common among African-American men. These patterns suggest that both genetic and environmental factors may play a role in who develops the disease.[2][5]
What Causes Testicular Cancer?
The exact cause of testicular cancer is not fully understood. Scientists know that it develops when cells in the testicle begin to multiply much faster than normal. These rapidly dividing cells eventually form a lump or mass called a tumor. In most cases, testicular cancer begins in what are called germ cells, which are the cells that eventually develop into sperm.[2]
About 90% of testicular cancers arise from these germ cells. The cancer cells can grow quickly and often spread beyond the testicle to other parts of the body, such as the lymph nodes in the abdomen, the lungs, or other organs. Despite this tendency to spread, the cancer remains highly responsive to treatment.[2]
Both genetic and environmental factors appear to contribute to the development of testicular cancer. However, researchers have not identified a single cause. Instead, a combination of inherited traits and life circumstances seems to increase the likelihood that abnormal cell growth will occur in the testicles.[3]
Types of Testicular Cancer
There are two main types of testicular cancer that develop from germ cells: seminomas and non-seminomas. These two types behave differently and require different treatment approaches.[2]
Seminomas are slower-growing cancers. They primarily affect men in their 40s or 50s. Because they grow more slowly, they may be easier to control, and they respond particularly well to radiation therapy. Non-seminomas, on the other hand, grow and spread more rapidly. They mainly affect younger men in their late teens, twenties, and early thirties. There are actually four different subtypes of non-seminoma tumors, each named after the type of germ cell involved: embryonal carcinoma, yolk sac carcinoma, choriocarcinoma, and teratoma.[2][4]
Some testicular tumors contain both seminoma and non-seminoma cells mixed together. When this happens, doctors treat the tumor as a non-seminoma because of the more aggressive nature of those cells. The type of cancer affects not only how it is treated but also how closely it needs to be monitored.[4]
Risk Factors for Testicular Cancer
A risk factor is anything that increases a person’s chances of developing a disease. Having one or more risk factors does not mean someone will definitely get testicular cancer, and many men who develop the disease have no known risk factors at all. However, understanding these risk factors can help men and their doctors stay alert to early warning signs.[2]
Age is one of the most important risk factors. Testicular cancer most commonly affects men between ages 15 and 35, though it can occur at any age. This makes it quite unusual compared to most other cancers, which tend to strike older individuals.[2]
Undescended testicles, also called cryptorchidism, is another significant risk factor. During fetal development, testicles form inside the abdomen and normally drop down into the scrotum before birth. When one or both testicles fail to descend, the risk of testicular cancer increases by two to four times. Interestingly, this increased risk remains even if surgery is performed to move the testicle into the scrotum. Since undescended testicles are more common on the right side, there is a slightly higher incidence of testicular cancer on the right side as well.[2][3]
Race and ethnicity also influence risk. Testicular cancer is more common among white men, particularly non-Hispanic whites, compared to men of other racial backgrounds. This pattern is seen both in the United States and in Europe.[2][5]
Other risk factors include certain genetic conditions such as Klinefelter Syndrome, as well as male infertility. Some of the same factors that cause fertility problems may also be linked to testicular cancer risk. Testicular trauma has also been studied as a potential risk factor, though the connection is not as clear. Some infections, including human papillomavirus (HPV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), parvovirus B-19, and HIV, have been associated with testicular cancer, as have high maternal estrogen levels during pregnancy.[2][3]
Symptoms and Warning Signs
The most common sign of testicular cancer is a painless lump or swelling in one of the testicles. This lump may be small or large, and it usually does not cause discomfort. Because it is painless, men may overlook it or delay seeking medical attention, thinking it will go away on its own. However, any new lump in the testicle should be checked by a doctor as soon as possible.[1][2]
Other symptoms include a feeling of heaviness in the scrotum, even without a visible lump. Some men notice swelling or a sudden buildup of fluid in the scrotum. There may be a dull ache in the lower abdomen or groin area, though this is less common. Some men experience pain or discomfort in a testicle or the scrotum, though again, the lump itself is usually painless. A testicle may also shrink, a condition known as testicular atrophy.[1][2][4]
In some cases, testicular cancer can cause symptoms outside the testicles. For example, if the cancer has spread to the lymph nodes in the abdomen, it may cause back pain. If it has spread to the lungs, it might cause a cough or shortness of breath. Rarely, testicular cancer can cause breast tissue to enlarge or become tender because certain tumors produce hormones that affect the body in unusual ways.[1]
These symptoms can also be caused by other conditions that are not cancer, such as infections, fluid buildup, or non-cancerous growths. However, it is important not to ignore them. Delaying a visit to the doctor gives cancer cells more time to grow and potentially spread, which can make treatment more difficult. Early detection is key to achieving the best possible outcome.[2]
How Testicular Cancer Is Diagnosed
If a man notices any symptoms that might suggest testicular cancer, the first step is usually a visit to a doctor. The doctor will ask about symptoms, medical history, and family history of cancer. A physical exam will be performed, during which the doctor will carefully check the testicles for lumps, swelling, or tenderness.[4]
If a lump or other abnormality is found, the next step is typically an ultrasound of the testicles. An ultrasound is a simple, painless test that uses sound waves to create pictures of the inside of the scrotum. During the test, the patient lies on his back with his legs spread, and a health care provider applies a clear gel to the scrotum. A hand-held device is moved over the area to produce images. The ultrasound can show whether a lump is inside or outside the testicle and whether it looks like cancer or something else. Lumps inside the testicle are more likely to be cancerous.[1][12]
Blood tests are also used to help diagnose testicular cancer. These tests look for tumor markers, which are substances released into the blood by certain types of cancer cells. The main tumor markers for testicular cancer are called alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (beta-hCG), and lactate dehydrogenase. Having higher than normal levels of these markers can suggest cancer, though it does not confirm it. These markers are also used to monitor treatment and check for recurrence after treatment is complete.[1][4][12]
The only way to definitively diagnose testicular cancer is through surgery to remove the affected testicle, a procedure called a radical inguinal orchiectomy. A small incision is made in the groin, and the entire testicle is removed through this opening. The testicle is then sent to a laboratory, where a tissue sample is examined under a microscope to check for cancer cells. This procedure serves both a diagnostic and a therapeutic purpose, as removing the testicle is often the primary treatment for testicular cancer.[5][12]
Pathophysiology: What Happens in the Body
Testicular cancer begins when germ cells in the testicle undergo abnormal changes. Instead of developing into normal sperm cells, these germ cells start to multiply uncontrollably. This rapid, uncontrolled growth leads to the formation of a tumor. The tumor is made up of cancer cells that do not function properly and continue to divide without the normal checks and balances that regulate cell growth.[2]
As the tumor grows, it can damage the normal tissue of the testicle. The testicle may become enlarged, lumpy, or feel different to the touch. The tumor can also affect the production of hormones and sperm. In some cases, the tumor produces hormones itself, leading to unusual symptoms like breast enlargement.[1]
One of the concerning features of testicular cancer is its tendency to spread, or metastasize, beyond the testicle. Cancer cells can break away from the original tumor and travel through the body via the lymphatic system or the bloodstream. The first place testicular cancer typically spreads is to the lymph nodes in the back of the abdomen, an area called the retroperitoneum. From there, it can spread to the lungs, liver, brain, or other organs. However, even when testicular cancer has spread, it often responds very well to treatment.[2]
Prevention and Early Detection
Unfortunately, there is no sure way to prevent testicular cancer because the exact causes are not fully known. However, there are steps men can take to catch the disease early, when it is most treatable.[4]
One of the most important things a man can do is perform regular testicular self-exams. This involves checking the testicles for any lumps, swelling, or changes in size or texture. The best time to do a self-exam is after a warm bath or shower, when the scrotum is relaxed. By feeling each testicle gently, a man can become familiar with what is normal for him and notice any changes early. If anything unusual is found, it should be reported to a doctor right away, even if there is no pain.[7]
Men with risk factors, such as a history of undescended testicles or a family history of testicular cancer, should be especially vigilant about self-exams and regular checkups. While there is no formal screening program for testicular cancer like there is for some other cancers, being aware of one’s own body and seeking prompt medical attention for any concerns is the best defense.[7]
For men with undescended testicles, early surgical correction in childhood may reduce some risks, though it does not eliminate the increased cancer risk entirely. Men with a personal history of testicular cancer in one testicle should be especially careful to monitor the other testicle, as the risk of developing cancer in the second testicle is higher.[2]
Treatment Options for Testicular Cancer
Treatment for testicular cancer depends on the type of cancer, its stage (how far it has spread), and the patient’s overall health. The first step in treatment is almost always surgery to remove the affected testicle. This procedure, called a radical inguinal orchiectomy, is both diagnostic and therapeutic. Removing the testicle eliminates the primary source of the cancer and allows doctors to examine the tumor tissue to determine the exact type and stage of cancer.[5][12]
For some men, particularly those with very early-stage cancer, surgery alone may be enough. After the testicle is removed, doctors may recommend active surveillance, which means closely monitoring the patient with regular checkups, blood tests, and imaging scans to watch for any signs that the cancer has returned. This approach avoids the side effects of additional treatments while still catching any recurrence early.[12]
Chemotherapy is a common treatment for testicular cancer, especially if the cancer has spread beyond the testicle or if there is a high risk of recurrence. Chemotherapy uses powerful medicines to kill cancer cells throughout the body. It can be very effective against testicular cancer, even in advanced stages. However, chemotherapy can cause side effects such as nausea, fatigue, hair loss, and damage to nerves in the fingers or feet, a condition called peripheral neuropathy. Some side effects are temporary, while others may be longer-lasting.[12][13][18]
Radiation therapy, which uses high-energy rays to kill cancer cells, is another treatment option, particularly for seminomas. Seminomas are more sensitive to radiation than non-seminomas. Radiation is typically directed at the lymph nodes in the abdomen to kill any cancer cells that may have spread there. Like chemotherapy, radiation can have side effects, including fatigue and irritation to the treated area.[12][13]
In some cases, surgery may be needed to remove lymph nodes in the abdomen, a procedure called retroperitoneal lymph node dissection (RPLND). This surgery can help determine if the cancer has spread and can remove any cancer that is present in the lymph nodes. If the cancer has spread to the lungs or other organs, additional surgery or treatment may be required.[12]
For men with advanced cancer that has not responded to standard treatments, high-dose chemotherapy combined with a stem cell transplant may be an option. This intensive treatment involves collecting the patient’s own stem cells, giving very high doses of chemotherapy to kill cancer cells, and then returning the stem cells to the body to help rebuild the bone marrow and blood system.[7]
Impact on Fertility and Sexual Health
One of the major concerns for young men diagnosed with testicular cancer is how the disease and its treatment will affect their ability to have children. Testicular cancer itself, as well as treatments like surgery, chemotherapy, and radiation, can all impact fertility.[4][18]
Before starting treatment, men who wish to have biological children in the future should discuss sperm banking with their doctors. Sperm banking involves collecting and freezing sperm samples, which can later be used for fertility treatments such as in vitro fertilization (IVF). This option should be considered before surgery, chemotherapy, or radiation, as these treatments can reduce sperm production or quality. Many men can preserve their fertility this way, giving them the option to start a family after treatment is complete.[7][13][18]
Having one testicle removed does not usually affect a man’s ability to produce testosterone or to father children, as long as the remaining testicle is healthy. However, if both testicles are removed or if chemotherapy and radiation damage sperm production, fertility may be permanently affected. In cases where both testicles are removed, testosterone replacement therapy can help maintain normal hormone levels and prevent symptoms of low testosterone, such as fatigue, low sex drive, and mood changes.[18]
Sexual function can also be affected by testicular cancer and its treatment. Some men worry about how their body will look after surgery, which can impact self-esteem and intimacy. A prosthetic testicle can be inserted during surgery to help restore a more natural appearance, which may help some men feel more comfortable and confident.[18]
It is normal for men to experience changes in sexual desire and function during and after cancer treatment. Fatigue, anxiety, and the physical effects of treatment can all play a role. Open communication with a partner and with healthcare providers is important. Counseling or support groups can also help men and their partners navigate these changes.[19]
Life After Testicular Cancer: Survivorship
Most men treated for testicular cancer will be cured and go on to live long, healthy lives. However, survivorship involves more than just being cancer-free. It means adjusting to life after cancer, managing any long-term effects of treatment, and staying vigilant about follow-up care.[17][18]
After treatment is complete, regular follow-up appointments are essential. These checkups typically include physical exams, blood tests to check tumor markers, and imaging scans such as CT scans or X-rays. The frequency of these appointments depends on the stage and type of cancer and the treatment received. Follow-up care helps detect any recurrence of cancer early, when it is most treatable. Men who have had testicular cancer in one testicle should also be vigilant about checking the other testicle regularly, as the risk of developing cancer in the second testicle is higher.[7][17]
Some treatments can cause long-term or late effects, which are side effects that appear months or years after treatment ends. Chemotherapy, for example, can cause hearing loss, nerve damage, or an increased risk of heart disease or other cancers later in life. Radiation can also have long-term effects on the organs in the treated area. Men should discuss these potential risks with their doctors and have a plan for monitoring and managing any late effects.[18]
Emotionally, survivorship can be a complex time. Many men feel relief and gratitude to be cancer-free, but they may also experience anxiety about recurrence, sadness, frustration, or anger. It is normal to have mixed emotions. Talking openly with family, friends, and healthcare providers can help. Some men find it helpful to connect with other survivors through support groups or online communities. Counseling or therapy can also provide valuable support for managing the emotional challenges of survivorship.[16][17]
Staying healthy after cancer involves taking care of both physical and mental well-being. Eating a balanced diet, exercising regularly, getting enough rest, and avoiding tobacco and excessive alcohol can all contribute to long-term health. Men should also be proactive about their healthcare, attending all follow-up appointments and reporting any new or unusual symptoms to their doctors.[17]