WBR0443

Author	[[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Alison Leibowitz) (Reviewed by Serge Korjian)]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Pathology
Sub Category	SubCategory::Endocrine
Prompt	[[Prompt::A 45-year-old female presents to the physician’s office with a painless mass in her neck. The physician, suspecting a thyroid disease, orders a thyroidectomy. A biopsy of the thyroid mass is illustrated below. Which of the following diagnoses most likely corresponds with the biopsy findings? ]]
Answer A	AnswerA::Hashimoto thyroiditis
Answer A Explanation	[[AnswerAExp::Hashimoto thyroiditis, the most common cause of hypothyroidism, is an autoimmune disease that is characterized on biopsy by lymphocytic infiltration with germinal centers.]]
Answer B	AnswerB::Reidel thyroiditis
Answer B Explanation	[[AnswerBExp::Reidel thyroiditis is a benign thyroid disease characterized by fibrosis of thyroid tissue going beyond the borders of the thyroid gland.]]
Answer C	AnswerC::Follicular thyroid cancer
Answer C Explanation	[[AnswerCExp::Follicular thyroid cancer is the only thyroid cancer that cannot be diagnosed by FNA. Biopsy demonstrates uniform follicles.]]
Answer D	AnswerD::Medullary thyroid cancer
Answer D Explanation	[[AnswerDExp::Medullary thyroid cancer, diagnosed by FNA, is a cancer of the parafollicular, or C cells, of the thyroid gland. On pathology, medullary thyroid cancer manifests as sheets of cells in amyloid stroma.]]
Answer E	AnswerE::Papillary thyroid cancer
Answer E Explanation	[[AnswerEExp::On pathology of Papillary thyroid cancer, the most common thyroid cancer, there is papillary architecture.]]
Right Answer	RightAnswer::E
Explanation	[[Explanation::Papillary thyroid cancer (PTC), the most common thyroid malignancy accounting for more than 70% of all thyroid cancers, is associated with an excellent prognosis and an overall survival rate approximating 90%. Diagnosis of PTC is by fine needle aspiration (FNA). First line treatment for PTC is thyroidectomy. On pathology, PTC manifests with characteristic papillary projections on the thyroid tissue. Other characteristic features of PTC are psammoma bodies and large clear areas within nuclei frequently called “orphan annie eyes”. Educational Objective: On pathology, papillary thyroid carcinoma (PTC) manifests with characteristic papillary projections on the thyroid tissue. Other characteristic features of PTC are psammoma bodies and large clear areas within nuclei frequently called “orphan annie eyes”. References: First Aid 2014 page 323]]
Approved	Approved::Yes
Keyword	WBRKeyword::Papillary thyroid cancer, WBRKeyword::Cancer, WBRKeyword::Biopsy, WBRKeyword::Psammoma bodies, WBRKeyword::Thyroid, WBRKeyword::FNA, WBRKeyword::Carcinoma
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::