How is skin cancer diagnosed? 

It is important that your doctor establishes the diagnosis and type of skin cancer, assesses the extent of the cancer and whether it has spread to the lymph nodes.

To answer these questions your doctor will need to do the following things:

  • talk with you about changes to your skin/mole (if any) and discuss other health conditions and medications you are taking (called a medical history)

  • use an instrument (dermatoscope) to view the mole clearly

  • order some tests

Common tests include:


This involves removing a small piece (sample) from the cancer. The sample is then examined under a microscope to check for cancer cells. This is often the only sure way to tell if you have cancer.
Your doctor may recommend: 
  • Excision biopsy: to remove the cancer completely with a narrow margin; or if the cancer is large. This may be done in the clinic or in the operating room under general anaesthesia

  • Incision biopsy: this is when a doctor removes a small amount of tissue from the affected area using a surgical knife. These are commonly done in the doctor’s office

For both types of biopsy, your doctor will inject the area with an anaesthetic so that you don’t feel any pain. Depending on the size and location of the biopsy, you may need stitches. There may be some bleeding after the biopsy. If you take blood thinners (e.g. warfarin), you may need to stop these before the biopsy.

If the physical examination or other procedures suggest that the cancer has spread to the lymph nodes, your doctor may order a:
  • Needle biopsy (also called Fine Needle Aspiration of FNA): This is used when there is a lump (enlarged lymph node) in your neck that could have cancer cells in it. This is done by a radiologist or pathologist using an ultrasound to see that the needle is in the right spot. You may feel a bit uncomfortable during the biopsy.

  • Core biopsy: This is used to get more tissue in the biopsy. This is called a core biopsy. It can provide more information than needle biopsy but can be more uncomfortable. Your doctor will decide the type of biopsy that is most appropriate for you.