The testicles

From puberty the collecting tubules inside the testicles produce sperm, which can fertilise a female egg. The testicles are the main organs of the male reproductive system.

The tubules form a coiled tube called the epididymis. This feels like a soft swelling at the back of the testicle. The epididymis carries on to the outside of the testicle and widens to become the spermatic cord (or the vas deferens). This joins to the ejaculatory duct where sperm is mixed with a fluid called semen (made by the prostate gland) before it is ejaculated out of the penis.

The structures of the testicle

Lymph nodes

Sometimes cancer cells from the testicle can spread to nearby lymph nodes (also known as glands). Your doctors may talk to you about this, so it can be helpful to understand a bit more about it.

Lymph nodes are small and round and we have lots of them throughout the body. They’re connected to each other by a network of tiny lymphatic vessels that carry a fluid called lymph, which contains cells that help us fight infection. This is a part of our immune system − the body’s natural defence against infection.

The lymph system in the abdomen

Cancer cells can be picked up by the lymph fluid and carried to lymph nodes in other parts of the body. Lymph vessels in your testicles carry fluid to a collection of lymph nodes at the back of your tummy (abdomen). They lie just behind your bowel and in front of your spine and are called the retroperitoneal lymph nodes. You’ll have a scan (CT scan|) to check if any of these nodes are larger than normal.