What should you know about substernal goitre?

The thyroid normally sits low in the front of the neck. With a substernal goitre, part of the enlarged gland reaches into the upper chest. It may cause no obvious neck lump, yet can create pressure, a cough, noisy breathing, breathlessness when lying down, hoarseness, or difficulty swallowing. Thyroid hormone production may be normal, increased, or reduced, so the size of the gland and hormone symptoms are separate questions. Examination and imaging help show the gland’s position and its relationship to the airway and nearby structures.

Arrange a GP consultation for a new neck swelling, pressure sensation, persistent cough, voice change, or swallowing difficulty. Take a list of medicines and mention weight change, heat or cold intolerance, tremor, palpitations, constipation, and tiredness. A thyroid function test can help assess hormone activity; further imaging may be recommended to map the extension into the chest. Do not massage the swelling or delay review because it is not painful. Follow-up depends on symptoms, gland size, hormone results, and imaging findings.

Seek emergency help if you develop severe or rapidly worsening breathlessness, noisy breathing, inability to swallow saliva, blue lips, or sudden swelling of the neck. Obtain prompt medical advice for new hoarseness, worsening swallowing trouble, faintness, or breathlessness that is worse when lying flat. These symptoms can indicate pressure on the airway or food pipe and should not be assessed by symptoms alone.

How far does the thyroid extend below my breastbone, and is it affecting my airway? Are my thyroid hormone levels normal? Which scan or follow-up is appropriate? What symptoms would mean I need urgent help?