Testicular cancer receives more publicity today than ever before, yet is still an uncommon cancer, with approximately 1,500 new cases diagnosed each year.

It is also a highly treatable condition, and in many cases the man is still able to father children following treatment.

Testicular cancer affects either one or both testicles.

Men are now urged to check for the warning signs of cancer so that treatment can begin as soon as possible.

Professor Alan Horwich, a testicular cancer expert who carries out research for the Cancer Research Campaign, said: "It's a very highly curable illness if detected early.

"What we would encourage young men to do is to report to their GP if they do feel any change in their testes.

"It has been slowly getting more common over the last 50 or 60 years - the only interesting clue we have is that there is a cohort of men born just after the Second World War who developed it."

There are various different types of testicular cancer, affecting the different types of cells which make up the testicle.

Click here to listen to Professor Alan Horwich talking about testicular cancer

The most common sign which may turn out to be testicular cancer is a lump or swelling, usually painless.

Men are encouraged to check themselves regularly for these, ideally after a hot bath or shower, which relaxes the muscles and makes this easier.

Click here to hear how Alex Lindsay faced testicular cancer

The growing tumour may also make the testicle feel heavy, produce discomfort in the groin area, or make the testicle or the scrotal sac painful.

There are a number of techniques commonly used to confirm whether these symptoms are caused by cancer, or something less sinister.

When testicular cancer is present, blood tests can reveal the presence of certain chemicals called "tumour markers" which are not around at such high levels normally.

Doctors examine lumps in the testicle using ultrasound, or simply take a small sample in a minor operation.

This is then looked at further in the laboratory.

Once cancer is confirmed, the doctor may use other tests such as CT scans to check to see whether it has spread beyond the testicle to involve other organs and parts of the body.

Treatment for testicular cancer involves removing the affected testicle, although in many cases the other one can be preserved if the doctor is confident the disease has been caught early and has not spread.

One testicle can produce enough sperm to produce children, and testicular removal does not affect the level of male sex hormones, or the ability to get an erection.

However, if there is a suspicion of spread, then lymph nodes in the groin area may have to be taken out for analysis - this could affect the ability to ejaculate semen at orgasm.

Depending on the spread of the disease, additional radiotherapy or chemotherapy may be necessary.

While radiotherapy does not permanently remove fertility in most cases, or chemotherapy is more likely to result in a permanent reduction or removal of sperm production.

If there is any chance that fertility could be damaged, sperm can be frozen and then used in in-vitro fertilisation (IVF) later in life.

Doctors do not know precisely what causes testicular cancer, but they have spotted some clues.

They have found that men whose testicles did not develop properly, such as men who had undescended testicles as a baby, are at increased risk.

Men who have suffered testicular cancer in one testicle are far more likely to get it again in another testicle.

To learn more about survival rates for testicular cancer compared to other cancers, click here .