Textbook
1. Anatomy
2. Microbiology
3. Physiology
4. Pathology
4.1 General pathology
4.2 Central and peripheral nervous system
4.3 Cardiovascular system
4.4 Respiratory system
4.5 Hematology and oncology
4.6 Gastrointestinal pathology
4.7 Renal, endocrine and reproductive system
4.7.1 Renal system
4.7.2 Diabetes mellitus
4.7.3 Diabetic symptoms
4.7.4 Metabolic syndrome or Syndrome X
4.7.5 Thyroid disorders
4.7.6 Hypothyroidism
4.7.7 Hyperthyroidism
4.7.8 Malignancies of the thyroid gland
4.7.9 Parathyroid disorders
4.7.10 Hypoparathyroidism
4.7.11 Adrenal disorders
4.7.12 Adrenal insufficiency
4.7.13 Cushing’s syndrome
4.7.14 Additional information
4.8 Musculoskeletal system
5. Pharmacology
6. Immunology
7. Biochemistry
8. Cell and molecular biology
9. Biostatistics and epidemiology
10. Genetics
11. Behavioral science
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4.7.8 Malignancies of the thyroid gland
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4. Pathology
4.7. Renal, endocrine and reproductive system

Malignancies of the thyroid gland

It can be anaplastic, follicular, medullary or anaplastic types on microscopy. Risk factors include family history, female sex and previous neck irradiation. Non Hodgkin’s lymphoma is seen in Hashimoto’s thyroiditis. Anaplastic carcinoma has a bad prognosis. It presents with a neck mass, thyroid nodule, lymphadenopathy, dysphagia, dyspnea, fatigue and weight loss. Evaluation is with ultrasound which shows microcalcifications, increased vascularity and hypoechoic mass. Ultrasound is followed by biopsy. Iodine scan may show a cold or hot nodule. Serum thyroglobulin is a tumor marker for thyroid cancers. Treatment is by thyroidectomy with RAI or radioiodine ablation and TSH suppression. Lobectomy is done for small nodules without local or distant spread. RAI helps to control distant metastases. TSH suppression is done by administering thyroid hormone. Total thyroidectomy is done for lesions greater than 1 cm. Lymph node dissection is done in the presence of metastatic lymphadenopathy. Medullary carcinoma is always treated by thyroidectomy, calcitonin can be used as a tumor marker.

Types of thyroid cancers

Type Features
Papillary RET and BRAF mutations; multiple foci; shows papillary projections, Psammoma bodies, Orphan Annie nuclei
Follicular Abnormal follicles, capsular and vascular invasion
Medullary Origin from parafollicular C cells, amyloid deposits, calcitonin positive; associated with MEN 2A and B; RET mutations
Anaplastic P53 and BRAF mutations; poorly differentiated, giant cells

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