Thyroid cancer is usually asymptomatic in early stages and often discovered incidentally. As the tumor enlarges or invades adjacent structures, the following may develop: Painless neck lumpMost common first sign—unilateral, firm, poorly mobile on swallowing, slowly but steadily enlarging . HoarsenessPersistent and unrelenting hoarseness due to recurrent laryngeal nerve invasion and vocal-cord palsy . DysphagiaCompression or invasion of the oesophageal entrance causes globus sensation and progressive difficulty swallowing solids . DyspnoeaTracheal compression or intraluminal growth produces inspiratory stridor and orthopnoea that worsen when lying flat . Cervical lymph-node swellingFirm, matted nodes in the lateral neck often indicate regional metastasis .... Learn more