1. THYROID GLAND

2. MUST KNOW
How to examine the neck and diagnose thyroid enlargement from other neck lumps.
Clinical presentation of hypo and hyper
Meaning and interpretaion of thyroid function tests.
How to investigate and manage a patient with STN
Clinical features ,dx and management of thyroid neoplasms

3. ANATOMY AND PHYSIOLOGY
WHY DOES THE YHROID MOVE ON SWALLOWING.

11. MIDLINE SWELLINGS
Thyroid enlargement
Thyroglossal cyst
Dermoid cyst

12. HYPOTHYROIDISM
F:M 10:1
Due to commonly hashimotos[TPO AND ANTI THYROGLOBULIN IS RAISED]
Symptoms and signs
Exam
Lymphoma can develop on a back ground of autoimmune disease
TSH,T4 ,T3
TX Thyroxine

13. hyperthyroidism Causes include Grave’s Toxic multinodular goiter
Solitary toxic adenoma
Tx with thyroid uptake drugs
radioactive iodine
surgery

14. MNG Majority are non toxic Some can become toxic ( plummers disease)
May extend retrosternally if large causing trachael deviation, compression and strider
O/E multinodular if there is dominant nodule then this should be investigated as the risk of malignancy in this nodule is about 10%.

19. TSH : Low if toxic
FNA US
X-ray of thoracic inlet
Tx – Total for non-toxic if there is retrosternal ext., trachael comp or cosmotically unacceptable
If toxic - tx first the either total or radioactive iodine

23. SOLITARY THYROID NODULE
5% Of female population. But only 5% are malignant.
Causes 1- thyroid cyst
2- degenerative thyroid nodule
3- benign follicular adenoma
4- differentiated thyroid ca

24. History
Feature suggestive of malignancy
1- previous irradiation (as a child)
2- hoarsness
3- family Hx (papillary)

25. Investigation
Exclude solitary toxic adenoma (where TSH is suppressed) + malignancy therefore TSH and FNA most important
If suspicious on FNA then for surgery as 30% are malignant
Ultrasound to distinguish solid from cystic or dominant nodule within MNG (50% STN)

26. Isotope scan Increase uptake = hot
Decreased uptake = cold
Treatment

27. Thyroid tumours Benign thyroid tumours Most are follicular adenomas
Papillary adenomas are rare
All papillary tumours should be considered malignant

28. Follicular adenoma
Of all follicular lesions-80% benign and 20% malignant
They are smooth and discrete lesions with glandular or acinar pattern
They are incapsulated usually 2-4 cm in diameter
Adenomas can not be differentiated from carcinoma on FNA cytology
Requires histological assessment of capsular invasion

29. Malingnat thyroid tumours
Differentiated thyroid cancer accounts for 80% of thyroid neoplasms
Female : Male ratio is 4:1
Usually presents as solitary thyroid nodule in young/middle age adult
Nodule more likely to be malignant in man or child
Papillary and follicular tumours are biologically very different

30. Comparison of papillary and follicular tumours
Papillary tumours Follicular tumours
Multifocal Solitary
Unencpasulated Encapsulated
Lymphatic spread Haematogenous spread
Metastasize to Metastasize to lung.
regional bone and brain

31. Papillary and mixed tumours
Accounts fro 70% Of Ca. thyroid.
20-40 yrs
50% tumours are less than 2cm diameter at presentation
Tumours less than 1cm diameter regarded as minimal or micropapillary lesoins
Psammoma bodies and “orphan Annie” nuclei are characteristic histologicalfeatures

32. 30%-50% are multicentric with simultaneous tumour in contralateral lobe
Early spread occurs to regional lymph nodes
Thyroid lobectomy adequate for minimal lesions
Total thyroidectomy is otherwise surgery of choice

33. Many tumours are TSH dependent
TSH suppression with post-operative thyroxine appropriate
Thyroxine reduces recurrence and improves survival
80% nodes have microscopic involvement
Role of prophylactic lymph node dissection at time of initial surgery unclear

34. Lymph node dissection does not improve survival
Alternative is to sample the lymph nodes
If negative-no further surgery
If positive-modified neck dissection
Prognosis excellent (90% 20 yrs)

35. Follicular tumours 40 – 50 yrs
Can not differentiate follicular adenoma and carcinoma on FNA cytology
Treatment of all follicular neoplasms is thyriod lobectomy with frozen section
If frozen section confirms carcinoma- total thyriodectomy
If frozen section confirms adenoma-No further surgery required
Total thyroidectomy allows detection of metastased using 123/Scanning during follow up
All patients require suppressive thyroxine therapy

36. Follow up of thyroid carcinoma
Annual isotope scanning to detect asymptomatic recurrence
Treatment of such recurrence can still be curative
Serum thyroglobulin-increasing levels often first sign of recurrence

37. Anaplastic carcinoma Accounts for less than 5%thyroid malignancies
Occurs in elderly and is usually an aggressive tumour
Local infilteration causes dysponea and dysphagia
Thyriodectomy seldom feasible
incision biopsy should be avoided as it often causes uncontrollable local spread
Radiotherapy and chemotherapy important modes of treatment
Death usually occurs within 6 months

38. Thyroid lymphoma Accounts for 2% of thyroid malignancies
Often arises with Hashimotos thyroiditis or non-Hodgkins B-cell lymphoma
Presents as a goitre in association with generalized lymphoma
Diagnosis can often be made by FNA cytology
Radiotherapy is treatment of choice
Prognosis is good – often more than 85% 5 yr survival

39. Medullary carcinoma 8% Para-follicular C-cells 20% are familial
Can occur as part of MEN 2
80% of cases are sporadic
Sporadic cases usually unilateral
50% have lymph nodes at presentation
Familial cases often multifocal and bilateral
Tumours mets to nodes and via blood to bone, liver and lung
They produce calcitonin,
Total thyroidectomy is treatment of choice
Calcitonin can be used in follow up for the presence of metastatic disease

40. THANK YOU