Many testicular cancers first develop in the germ cells.² These are the cells that make sperm.² There are two main types of germ cell cancer called ‘seminomas’ and ‘non-seminomas’:³

• Seminomas - tend to develop at a slower rate than non-seminoma cancers
• Non-seminomas - tend to develop more quickly compared to seminoma cancers, there are four sub-types of non-seminomas; embryonal carcinoma, yolk sac tumour, choriocarcinoma, and teratoma

Sometimes testicular cancer can be made up of both types of germ cell cancer - this is known as a mixed tumour. When this occurs, the approach is to treat the cancer as if it were a non-seminoma cancer.³

Testicular cancer may have minimal symptoms which may include:^3-5:

• A lump or swelling in the testicles, which is usually painless
• Change in size or shape in the testicles
• A heavy or uneven feeling in the scrotum
• Aching in a testicle, back or abdomen
• Back pain

These are not all the possible symptoms of testicular cancer.^3-5 Symptoms and their severity can vary between individuals. If you are concerned or have any questions, please speak with your GP or specialist.

The exact cause of testicular cancer is unknown.^4,6 However, there are some factors that may increase the risk of the development of testicular cancer, including:^3,4,6

• Family history of testicular cancer, such as your father or brother who has had testicular cancer
  
• An undescended testicle during infancy
• Infertility
• HIV or AIDS
• Abnormal development of the testicles
• Cannabis use – there has been some evidence that links regular use of cannabis to the development of testicular cancer
• Personal history – if you have had cancer in one testicle you are more likely to develop cancer in the other testicle
• An abnormality of the penis called hypospadias

If you have any questions or concerns about risk factors regarding testicular cancer, please make an appointment to speak with your GP or specialist.

A range of tests may be performed to make a diagnosis. Following a physical examination, which may include an examination of your testicles for any lumps or swelling, further tests may include:^2,3

• Imaging scans - That may include X-ray, ultrasound, magnetic resonance imaging (MRI) scan, and computed tomography (CT) scan
• Blood tests - A blood test may be taken to look for tumour markers in the bloodstream, as these may indicate cancer. The three tumour markers relevant to testicular cancer are alpha-fetoprotein, beta human chorionic gonadotrophin, and lactate dehydrogenase.
• Surgery - Rather than a biopsy, which is often used to help diagnose other forms of cancer, surgery can be used to definitively diagnose testicular cancer. This is because a biopsy cut into a testicle could spread the cancer to other parts of the body. If testicular cancer is strongly suspected, surgical removal of the whole testicle may be recommended.

If you are found to have testicular cancer your doctor will be able to speak to you about how far the cancer has progressed, and about potential treatment options to consider.

Testicular cancer is commonly staged with the ‘TNM system’, these letters stand for:^7,8

• Tumour: your doctors will measure the size of the tumour and how much it has grown
• Nodes: refers to whether cancer has spread to lymph nodes
• Metastasis: refers to whether cancer has spread to other parts of the body

Chemotherapy is an approach to cancer therapy which involves the administration of medicine, usually orally or by injection, which is intended to kill cancer cells or minimise their growth and spread. Chemotherapy can be used in conjunction with other cancer treatments

Radiation therapy uses high-energy X-rays or other particles to treat cancer and can be used at all stages

Surgery may be one treatment option that your doctor recommends. Surgery is usually used to remove the affected testicle, and this procedure is called an orchidectomy.