Thyroid Cancer B&B Flashcards
follicular adenoma (of the thyroid)
benign proliferation of follicles, common cause of thyroid nodules
normal follicular tissue completely surrounded by a fibrous capsule
note that fine needle aspiration cannot distinguish between adenomas/cancer because it will not show whether the mass is completely surrounded by its capsule (follicular carcinoma has similar histology)
A patient has their thyroid removed due to a suspicious mass. Histological examination of the thyroid after it is removed shows normal follicular tissue completely surrounded by a fibrous capsule. What kind of growth did they have?
follicular adenoma - benign proliferation of follicles, completely surrounded by fibrous capsule
fine needle aspiration cannot tell if it is completely surrounded, so thyroid must be removed for this diagnosis to be made
what is the most common form of thyroid cancer and how does it present?
papillary carcinoma: presents as thyroid nodule, sometimes seen on chest/neck imaging (CT/MRI), diagnosis made with fine needle aspiration (FNA)
prior radiation exposure is major risk factor
excellent prognosis, treated with surgery + radioactive iodine thyroid ablation
what major risk factor is associated with developing papillary carcinoma of the thyroid?
prior radiation exposure is major risk factor
papillary carcinoma: most common thyroid cancer, excellent prognosis, treated with surgery + radioactive iodine thyroid ablation
what are 3 key pathology findings of thyroid papillary carcinoma?
- psammoma bodies: calcifications with layered pattern (looks like a rose), not specific to thyroid cancer
- nuclear grooves: dark lines seen cutting through the nucleus*
- Orphan Annie’s Eye nuclei: empty-appearing nuclei*
*diagnostic for papillary carcinoma
A mass is detected on a patient’s thyroid, and fine needle aspiration is used to take a biopsy. Nuclear grooves and empty-appearing nuclei are seen under the microscope. The patient used to work in a factory with significant radiation exposure. What is the most likely diagnosis, and how will you treat them?
papillary carcinoma: most common thyroid cancer, associated with radiation exposure, histology includes nuclear groves and Orphan Annie Eye (empty) nuclei
excellent prognosis, treat with surgery + radioactive iodine thyroid ablation
how is follicular carcinoma of the thyroid diagnosed?
histology looks the same as follicular adenoma (benign), and fine needle aspiration cannot distinguish
however in follicular carcinoma, the mass breaks out of the fibrous capsule
so basically the growth is followed over time, and if it grows then surgery is done to remove the thyroid
follicular adenoma vs follicular carcinoma (of the thyroid)
follicular adenoma: benign proliferation of follicles, completely surrounded by fibrous capsule
follicular carcinoma: same histology as follicular adenoma, but breaks out of fibrous capsule
[must follow mass over time to distinguish between these by monitoring for new growth]
what is unusual about the way in which follicular carcinoma of the thyroid spreads?
most carcinomas spread via lymph nodes; however, follicular carcinoma of the thyroid is able to metastasize via the blood (hematogenous)
treat with thyroidectomy + high dose radioactive iodine to ablate any remaining tissue or metastasis
what cells cause medullary carcinoma of the thyroid and how does it present?
cancer of parafollicular / C cells which produce calcitonin (“tone” down serum calcium) —> presents as hypocalcemia
amyloid deposits seen in the thyroid (amyloid = protein deposits and calcitonin = peptide)
This type of thyroid cancer is caused by malignancy of the parafollicular cells, and biopsy shows amyloid deposits. What is?
medullary carcinoma: cancer of parafollicular / C cells which produce calcitonin (“tone” down serum calcium) —> presents as hypocalcemia
amyloid deposits seen in the thyroid (amyloid = protein deposits and calcitonin = peptide)
A patient has their thyroid biopsied due to a suspicious mass. Histological analysis shows malignant proliferation of the parafollicular cells surrounded by “amyloid stroma.” What is the diagnosis?
medullary carcinoma: cancer of parafollicular / C cells which produce calcitonin (“tone” down serum calcium) —> presents as hypocalcemia
amyloid deposits seen in the thyroid (amyloid = protein deposits and calcitonin = peptide)
Which forms of MEN syndrome are associated with thyroid medullary carcinoma, and what mutation is responsible?
MEN 2A and 2B (multiple endocrine neoplasia): caused by RET oncogene mutation
some patients undergo elective thyroidectomy for prevention
A patient with a family history of thyroid cancer decides to speak with a genetic counselor (you). Their DNA is genotyped and comes back positive for a mutation which causes MEN 2A and 2B. What mutation is this, and how will you counsel them regarding their concerns of thyroid cancer?
MEN 2A/B (multiple endocrine neoplasia): caused by RET oncogene mutation
associated with risk for medullary carcinoma of thyroid (malignant proliferation of parafollicular/ C cells)
some patients under elective thyroidectomy for prevention
how does anaplastic carcinoma of the thyroid present?
aka undifferentiated carcinoma (cells are undifferentiated)
occurs in elderly and is highly malignant - invasion of local tissues can cause dysphasia (esophagus), hoarseness (recurrent laryngeal nerve), dyspnea (trachea)
poor prognosis
