Thyroid cancer symptoms typically affect the thyroid gland located in the neck. The most common symptoms include a lump or swelling in the thyroid gland, hoarseness or changes in voice, difficulty swallowing, neck and throat pain, difficulty breathing, and a persistent cough. Additionally, some patients may experience fatigue and general weakness. These symptoms result from abnormal cell growth in the thyroid gland and the tumor pressing on surrounding tissues. For instance, a swollen thyroid gland can press on the windpipe or esophagus, leading to breathing and swallowing difficulties or a cough. Pressure on the vocal cords can cause hoarseness. Sometimes, thyroid cancer may not show any distinct symptoms and can be incidentally discovered during a doctor's examination or imaging tests performed for other reasons.