WBR0443
| Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pathology |
| Sub Category | SubCategory::Endocrine |
| Prompt | [[Prompt::A 45 year old female patient presents to her physician’s office for a painless mass in her neck. The physician suspects a thyroid disease. Following thyroidectomy, a biopsy of the thyroid mass is shown in the image below. What is the most likely diagnosis?
|
| Answer A | AnswerA::Hashimoto thyroiditis |
| Answer A Explanation | AnswerAExp::Hashimoto thyroiditis is the most common cause of hypothyroidism. It is an autoimmune disease that is characterized on biopsy by lymphocytic infiltration with germinal centers. |
| Answer B | AnswerB::Reidel’s thyroiditis |
| Answer B Explanation | AnswerBExp::Reidel’s thyroiditis is a benign thyroid disease characterized by fibrosis of thyroid tissue that goes 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 shows uniform follicles. |
| Answer D | AnswerD::Medullary thyroid cancer |
| Answer D Explanation | AnswerDExp::Medullary thyroid cancer is a cancer of the parafollicular or C cells of the thyroid gland. It is diagnosed by FNA. On pathology, medullary thyroid cancer shows sheets of cells in amyloid stroma. |
| Answer E | AnswerE::Papillary thyroid cancer |
| Answer E Explanation | AnswerEExp::Papillary thyroid cancer is the most common thyroid cancer. On pathology, there is papillary architecture. |
| Right Answer | RightAnswer::E |
| Explanation | [[Explanation::Papillary thyroid cancer (PTC) is the most common thyroid malignancy accounting for more than 70% of all thyroid cancers. It is associated with an excellent prognosis with overall survival approximating 90%. Diagnosis of PTC is by fine needle aspiration (FNA). First line treatment for PTC is thyroidectomy.
On pathology, PTC shows thyroid tissue that has characteristic papillary projections. Other characteristic features that are not shown in the above image are psammoma bodies and large clear areas within nuclei called “little orphan annie eyes”. Educational Objective:
Papillary thyroid cancer (PTC) on pathology shows thyroid tissue that has characteristic papillary projections. Other characteristic features that are not shown in the above image are psammoma bodies and large clear areas within nuclei called “little orphan annie eyes”. |
| Approved | Approved::No |
| Keyword | WBRKeyword::Papillary, WBRKeyword::thyroid, WBRKeyword::cancer |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |
