How is skin cancer diagnosed?

Physical examination

If you notice any changes to your skin, your doctor will look carefully at your skin and examine any spots you think are unusual. The doctor may use a handheld magnifying instrument called a dermoscope to examine the spots more closely.

Skin biopsy

If the doctor feels they can diagnose the skin cancer by examining the spot, you may not need any further tests before having treatment. However, it’s not always possible to tell the difference between a skin cancer and a non-cancerous skin spot just by looking at it. If there is any doubt, the doctor may need to take a tissue sample (biopsy) to confirm the diagnosis.

A biopsy is a quick and simple procedure that is usually done in the doctor’s office. You will be given a local anaesthetic to numb the area, then the doctor will either:

• completely cut out the spot and a small amount of healthy tissue around it (excision biopsy)
• take a small piece of tissue from the spot (punch or incision biopsy). Stitches may be used to close a larger wound and help it heal.

All tissue that is removed is sent to a laboratory, where a pathologist will examine it under a microscope. The results will be available in about a week.

If all the cancer and a margin of healthy tissue are removed during the biopsy, this may be the only treatment you need.

Can smartphone apps help detect skin cancer?

Some smartphone apps let you photograph your skin at regular intervals and compare the photos to check for changes. These apps may be a way to record any spot you are worried about or remind you to check your skin. However, research shows apps cannot reliably detect skin cancer and should not replace a visit to your GP or dermatologist. If you notice a spot that causes you concern, make an appointment with your doctor straightaway.