What are the main signs of thyroid cancer? Thyroid cancer is rare but is curable if diagnosed early. Signs of thyroid cancer include: A painless swelling or lump (nodule) in the front, lower part of your neck Hoarse voice Difficulty in swallowing and awareness of pressure when swallowing Difficulty in breathing, especially when sleeping If you discover a lump in your neck, or notice a change to an existing lump, it is important to see your GP without delay. Please remember that thyroid nodules and swellings are extremely common and 95% are benign (not cancer). See our thyroid cancer booklet Manage Cookie Preferences Please ensure Javascript is enabled for purposes of website accessibility