Symptoms

The main symptom of thyroid cancer is a lump in the front of the neck.

But thyroid cancer tends to develop slowly and there may not be any symptoms at first.

Neck lump

Thyroid cancer often causes a painless lump or swelling low down in the front of the neck.

However, neck lumps are common and are usually caused by a less serious condition, such as an enlarged thyroid (goitre). Only around 1 in every 20 neck lumps are cancer.

A neck lump is more likely to be cancer if it:

• feels firm
• does not move around easily under the skin
• gets bigger over time

See a GP if you have a swelling or lump at the front of your neck. While it's unlikely to be cancer, it's important to get it checked.

Other symptoms

Other symptoms of thyroid cancer include:

• swollen glands in the neck
• unexplained hoarseness that does not get better after a few weeks
• a sore throat that does not get better
• pain in your neck
• difficulty swallowing
• difficulty breathing

Rarely, thyroid cancer can affect the production of thyroid hormones and cause diarrhoea and flushing.

These symptoms can be caused by other conditions, but it's a good idea to see a GP if you develop any persistent symptoms that you're worried about.