Papillary and follicular thyroid cancer

well differentiated cancers of the thyroid

1. Papillary and follicular
thyroid cancer
K. A. Ikram Hussain
Final year M.B.B.S.

2. Papillary thyroid cancer
It is a relatively common well differentiated thyroid
cancer
Accounts for 85% of all thyroid cancers
It is more common in females than males
In more than 50% cases in spreads to lymphnodes of the
neck

3. Aetiology
Most thyroid cancers are sporadic
It can be a complication of Hashimoto’s thyroiditis
Familial and genetic syndromes are associated with
thyroid malignancies
Cowden’s syndrome
Gardner’s syndrome
Carney’s syndrome
Associated mutations: chromosomal translocations
involving RET proto-oncogene

4. Pathology
It is made of colloid filled follicles with papillary projections.
In some cases calcific lesions are found called psammoma bodies
Characteristic pale empty nuclei called Orphan Annie eye nuclei
are seen in some cases
Can present as cystic lesions
Can be multifocal involving both lobes
Lymph nodes and Lungs are the usual sites of metastases

5. Psammoma bodies

6. Orphan Annie eye appearance

7. Clinical presentation
Young females of age group 20-40 years are commonly
affected
Principal sign is a firm non tender nodule in thyroid area
with a hard consistency and ill defined borders
Signs of hoarseness, tracheal and esophagal
compression is present
Very often lymph nodes in lower deep cervical region
are involved and thyroid may or may not be palpable.

8. Prognostic criteria

9. Investigations
Thyroid profile
Ultrasound of thyroid and central neck
Fine needle aspiration cytology of the nodule
Serum thyroglobulin
TSH suppression test

10. Immunohistochemisty findings
Carcinoembryonic antigen (CEA) negative
Calcitonin negative
Thyroglobulin positive
Keratin positive

11. Treatment
Total thyroidectomy
After thyroidectomy, patients are given thyroid replacement therapy for
approximately 4-6 weeks. Thyroid replacement is then discontinued, to induce a
hypothyroid state and promote high serum thyroid-stimulating hormone (TSH)
levels.
Approximately 4-6 weeks after surgical thyroid removal, patients may have
radioiodine therapy to detect and destroy any metastasis and residual tissue in
the thyroid
A diagnostic dose of radioiodine (
131
 I or
123
 I) is then given, and a whole-body
scintiscan is performed to detect any tissue taking up radioiodine. If any normal
thyroid remnant or metastatic disease is detected, a therapeutic dose of
131
 I is
administered to ablate the tissue. The patient is then placed back on thyroid
hormone replacement (levothyroxine) therapy.
Therapy is administered until radioiodine uptake is completely absent
Long term surveillance: Thyroglobulin
Prognosis:95% adults survive over 10 years

12. Complications due to surgery and radio
iodine therapy
Hypothyroidism
Dysphagia
Vocal cord paralysis
Hypoparathyroidism
Sialoadenitis because radioiodine is taken up by the salivary glands
Pulmonary fibrosis in patients with large lung metastases
Brain edema in patients with brain metastases (may be prevented
by glucocorticoid therapy)
Permanent sterility and transient oligospermia or menstrual
irregularities
A small increase in the risk for leukemias or breast and bladder
carcinomas

13. Factors affecting poor outcome
Large primary tumor
Age > 45 years
Male sex
Lymph nodal metastases
Distant metastases
Multifocal disease
Extra-thyroidal extension

14. Follicular carcinoma of thyroid
It is a well differentiated tumor and 2
nd
most common
after papillary thyroid cancer
Incidence is 17% of cases
Follicular adenomas are 20% malignant and 80% benign

15. Aetiology
Follicular carcinoma usually arises in a multinodular
goitre especially in a cases of endemic goitre.
It should be suspected when multinodular goitre starts
growing rapidly

16. Pathology
Depending on invasion it is classified as
Noninvasive
Invasive refers to angio-invasion and capsular invasion

17. Angioinvasion

18. Clinical presentation
It can present as multinodular or solitary nodular goitre.
The diagnosis is confirmed after an ultrasound scan reveals features
of malignancy like microcalcifications
Metastasis in flat bones: when a patient with a thyroid swelling
presents with metastasis in the bone in the form of bony swelling or
pathological fractures, a diagnosis of follicular carcinoma can be
considered.
Common secondaries are flat bones like skull,ribs,sternum and
vertebral column because flat bones retain red marrow for a longer
time.
Clinical features of a secondary are: they are rapidly
growing,warm, vascular and pulsatile.

19. Metastasis to bone

20. Treatment
Treatment of primary:
Total thyroidectomy is always preferred
Treatment of the metastasis:
After total thyroidectomy a whole body scan is done to look for metastasis in
the bone. A single secondary can be treated with oral radioiodine therapy
followed by radiotherapy depending on the response to treatment
Multiple secondaries are also treated with oral radio iodine.
Postoperative thyroxine:
Postoperative period patient should receive thyroxine 0.3mg/day to suppress
TSH and to supplement thyroxine.
Prognosis: 15% mortality in 10 years.

21. Summary
Characteristics Papillary carcinoma Follicular carcinoma
Aetiology Sporadic/irradiation Endemic goitre
Incidence 60% 17%
Age (years) 20-40 30-50
Diagnosis Thyroid swelling with
lymphnode metastasis
Thyroid swelling with bony
metastasis
Microscopy Orphan Annie eye nuclei,
Psammoma bodies
Angioinvasion,
Capsular invasion
Spread Lymphatic Blood
Investigation FNAC Frozen section
Treatment of primary Subtotal/total
thyroidectomy
Subtotal/total
thyroidectomy
Treatment of metastasis Functional neck dissectionRadioiodine 131 iodine

22. Hurthle cell carcinoma
It is a variant of follicular cell carcinoma and more aggressive than follicular
cell carcinoma
These tumors are defined by presence of more than 75% of follicular cells
with oncocytic features.
Tumor contains sheets of eosinophilic cells packed with mitochondria
They secrete thyroglobulin
Even if hurthle cell adenoma is well encapsulated it is potentially malignant.
It does not take up iodine 131. hence less likely to respond to radioablation.
Mortality is high 20% in 10 years

23. Criteria to diagnose
Capsular or vascular invasion and distant metastasis
Higher chance of spread to lymph nodes compared to follicular thyroid
carcinoma
Higher chances of spread to distant sites too
TREATMENT:
Total thyroidectomy is the treatment of choice.
TSH suppression and follow-up is required regularly.

25. Follow up
Serum thyroglobulin- thyroid is the only organ which produces thyroglobulin.
Levels greater than 1-2mg/ml in patients receiving replacement thyroxine
therapy indicates presence of metastasis.
So serum thyroglobulin response to injected recombinant TSH is assessed
every year.
Ultrasound or MRI scans of neck for localisation of residual or recurrent
tumor