WBR0142
| Author | [[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by William J Gibson)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pathology |
| Sub Category | SubCategory::Endocrine |
| Prompt | [[Prompt::A previously healthy 27-year-old female patient presents to her primary care physician for generalized fatigue and difficulty concentrating for the past three months. She reports hair loss, dry skin, constipation and cold intolerance. Serology for antithyroid peroxidase antibodies is positive. This patient’s condition increases her risk of developing which of the following malignancies?]] |
| Answer A | AnswerA::Papillary carcinoma of the thyroid |
| Answer A Explanation | [[AnswerAExp::This patient has Hashimoto’s disease. It does not increase the risk of developing papillary carcinoma of the thyroid. Papillary carcinoma of the thyroid is the most common thyroid cancer. It is associated with BRAF (V600E) mutations that can now be treated with vemurafenib. Other genetic alterations involve NRAS point mutation and RET translocation (RET is NOT mutated, that is an error in First Aid).]] |
| Answer B | AnswerB::Follicular carcinoma of the thyroid |
| Answer B Explanation | AnswerBExp::This patient has Hashimoto’s disease. It does not increase the risk of developing follicular carcinoma of the thyroid. Follicular thyroid carcinoma is associated with good prognosis and is characterized by RAS mutations. |
| Answer C | AnswerC::Medullary carcinoma of the thyroid |
| Answer C Explanation | [[AnswerCExp::Medullary carcinoma of the thyroid is associated with Multiple Endocrine Neoplasia type IIB (MEN2B), but not with Hashimoto's thyroiditis.]] |
| Answer D | AnswerD::Lymphoma of the thyroid |
| Answer D Explanation | [[AnswerDExp::Thyroid lymphomas are associated with Hashimoto's thyroiditis.]] |
| Answer E | AnswerE::Anaplastic carcinoma of the thyroid |
| Answer E Explanation | AnswerEExp::This patient has Hashimoto’s disease. It does not increase the risk of developing anaplastic carcinoma of the thyroid. These tumors carry a poor prognosis and tend to occur in older patients. |
| Right Answer | RightAnswer::D |
| Explanation | [[Explanation::This patient is suffering from fatigue, constipation, cold intolerance and decreased concentration which are all suggestive of hypothyroidism. A positive test for antithyroid peroxidase antibodies is highly specific for Hashimoto's thyroiditis, an autoimmune disease in which these antibodies destroy the follicles of the thyroid. It is the most common cause of hypothyroidism and is associated with the HLA-DR5 serotype. Affected patients may show signs of hyperthyroidism early in the disease course, as thyroid hormone is released from disrupted follicles. However, patients eventually proceed to a hypothyroid state. On physical examination, patients often have a moderately enlarged, nontender thyroid. Laboratory finding in all hypothyroid patients include elevated TSH with decreased concentrations of free T3 and T4.
Hashimoto's thyroiditis is associated with increased risk of thyroid lymphoma. These tumors are typically non–Hodgkin's B-cell lymphomas and predominantly affect females over 70 years old. Giordano T. Symposium: Molecular underpinnings of thyroid cancer development and growth. Presented at: the 83rd Annual Meeting of the American Thyroid Association; Oct. 16-20, 2013; San Juan, Puerto Rico.]] |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Autoimmune, WBRKeyword::Thyroid, WBRKeyword::Thyroiditis, WBRKeyword::Cancer, WBRKeyword::Hashimoto's thryoiditis, WBRKeyword::Endocrinology, WBRKeyword::Lymphoma |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |