Cancer of the testicles, also known as testicular cancer, is one of the less common cancers. It usually affects younger men between the ages of 15 and 44.
The most common symptom is a painless lump or swelling in the testicles. Other symptoms can include:
- a dull ache in the scrotum (the sac of skin that hangs underneath the penis and contains the testicles)
- a feeling of heaviness in the scrotum
Read more about the symptoms of testicular cancer.
The testicles
The testicles are the two oval-shaped male sex organs that sit inside the scrotum on either side of the penis.
The testicles are an important part of the male reproductive system because they produce sperm and the hormone testosterone, which plays a major role in male sexual development.
Types of testicular cancer
The different types of testicular cancer are classified by the type of cells the cancer first begins in.
The most common type of testicular cancer is known as ‘germ cell testicular cancer’, which accounts for around 95% of all cases. Germ cells are a type of cell that the body uses to help create sperm.
There are two main subtypes of germ cell testicular cancer. They are:
- seminomas, which account for around 40% of all germ cell testicular cancers
- non-seminomas, which account for around 60% of all germ cell testicular cancers
Seminomas and non-seminomas tend to respond well to chemotherapy, a treatment that uses medication given directly into the bloodstream to kill cancer cells.
Less common types of testicular cancer include:
- Leydig cell tumours, which account for around 1-3% of cases
- Sertoli cell tumours, which account for around 1% of cases
This article focuses on germ cell testicular cancer. The Macmillan website has more information about Leydig cell tumour and Sertoli cell tumour.
How common is testicular cancer?
Testicular cancer is relatively uncommon, accounting for just 1% of all cancers that occur in men.
Each year in the UK around 2,090 men are diagnosed with testicular cancer, according to Cancer Research UK.
Testicular cancer is unusual compared to other cancers because it tends to affect younger men. As a result, although relatively uncommon overall, testicular cancer is the most common type of cancer to affect men between the ages of 15 and 44.
Rates of testicular cancer are five times higher in white men than in black men. The reasons for this are unclear.
The number of cases of testicular cancer that are diagnosed each year in the UK has roughly doubled since the mid-1970s. Again, the reasons for this are unclear.
Causes of testicular cancer
The cause or causes of testicular cancer are unknown, but a number of things have been identified that increase the chance of developing the condition. These include:
- having a family history of testicular cancer
- being born with undescended testicles (cryptorchidism). About 3-5% of boys are born with their testicles located inside their abdomen, which usually descend into the scrotum during the first four months of life
Read more about the causes of testicular cancer.
Outlook
Testicular cancer is one of the most treatable types of cancer. Over 95% of men with early stage testicular cancer will be completely cured.
Even cases of more advanced testicular cancer, where the cancer has spread outside the testicles to nearby tissue, have an 80% chance of being cured.
Compared to other cancers, deaths from testicular cancer are rare. Cancer Research UK say that around 70 men die from testicular cancer every year in the UK.
Treatment for testicular cancer includes the surgical removal of the affected testicle (which should not affect fertility or the ability to have sex), and chemotherapy. Less commonly radiotherapy, a treatment that uses radiation to kill cancer cells, may be used for seminomas.
Read more about treating testicular cancer.
