The thyroid gland can undergo goitrous transformation, where it becomes enlarged due to the formation of multiple nodules within it. The gland enlarges and causes pressure on other structures in the neck, such as the trachea (wind-pipe) and oesophagus. An enlarged gland may cause symptoms, such as difficulty swallowing, breathing or talking. Occasionally, the thyroid gland can enlarge downward into the chest, so it may become very large before it becomes clinically apparent.
An enlarged thyroid gland should be carefully assessed for suspicious features. Apart from a careful history and examination, further tests such as an ultrasound or CT scan and blood tests will help establish the extent of disease and if surgery is required.