Managing a swelling in the thyroid Mark Lansdown Leeds Teaching Hospitals Trust

This presentation will cover - basic revision difference between diffuse and localised swellings taking a good history investigation by the GP (should they be referred immediately or can we usefully scan them) what you do about them what GP's need to know about after care of thyroid cancer

Thyroid - basic revision first of the body's endocrine glands to develop, at day 24 of gestation develops from an endodermal thickening in the midline of the floor of the developing pharynx thyroglossal duct is obliterated, the distal part remaining as the pyramidal lobe C cells, which produce calcitonin, are of neural crest origin

Thyroid - basic revision 2 T4 and T3 produced by follicular cells initially as thyroglobulin stored in colloid Requires iodine (and selenium) TSH from anterior pituitary regulates production of thyroglobulin and release of T4 into circulation Active form of thyroxine is T3

Thyroid - basic revision 3 Thyroxine is essential for normal development and differentiation of probably all tissues of the body Act on most cells in the adult affecting metabolism, protein synthesis No pathognomonic symptoms of an under or overactive thyroid

Thyroid - difference between diffuse and localised swellings Diffuse goitre – Adolescence and pregnancy – Iodine deficiency – Thyroiditis – Early MNG Localised Swelling (5% population) – Dominant nodule MNG – Cyst – Adenoma – Carcinoma (5% of all nodules)

Thyroid - taking a good history Symptoms and signs of abnormal thyroid function – T4, TSH, TPO The “lump” – Since when?, has it changed?, associated symptoms Pain Voice change Medication Family history

Thyroid - investigation by the GP T4, TSH – Trends, drifting within the normal range? Thyroid peroxidase antibodies (TPO) – An anti-thyroid autoantibody Present in > 90 % Hashimoto’s thyroiditis Less commonly raised in Grave’s disease, MNG and thyroid cancer

Thyroid - investigation by the GP 2 Thyroid Ultrasound – Not recommended in the pathway for urgent referrals (2WW) – Highly operator dependent – Often needs to be repeated after referral Neck ultrasound – incidentalomas

Thyroids - what you do about them

What GP's need to know about after care of thyroid cancer Is thyroid cancer uncommon? – Incidence USA Breast 125/100,000 women Thyroid 20/100,000 women (6/100,000 men) – Prevalence Breast 3,000,000 Thyroid 600,000

What GP's need to know about after care of thyroid cancer 2 THS suppression <0.01 – Not always necessary in the low risk patient – Risk of side effects Anxiety, palpitations Bone health Cardiac health

What GP's need to know about after care of thyroid cancer 3 Local Guidelines (American)