View source for WBR0142

 {{WBRQuestion
|QuestionAuthor= {{Rim}} (Reviewed by William J Gibson and  {{YD}})
|ExamType=USMLE Step 1
|MainCategory=Pathology
|SubCategory=Endocrine
|MainCategory=Pathology
|SubCategory=Endocrine
|MainCategory=Pathology
|SubCategory=Endocrine
|MainCategory=Pathology
|MainCategory=Pathology
|MainCategory=Pathology
|MainCategory=Pathology
|SubCategory=Endocrine
|MainCategory=Pathology
|SubCategory=Endocrine
|MainCategory=Pathology
|SubCategory=Endocrine
|MainCategory=Pathology
|SubCategory=Endocrine
|MainCategory=Pathology
|MainCategory=Pathology
|SubCategory=Endocrine
|Prompt=A 27-year-old woman with no past medical history presents to her primary care physician for generalized fatigue and difficulty concentrating for the past three months. She has been smoking half a pack of cigarettes each day for the past 8 years and drinks alcohol occasionally. Upon review of systems, she reports hair loss, dry skin, constipation, and cold intolerance. Serology for anti-thyroid peroxidase antibodies is positive. This patient is at increased risk of developing which of the following malignancies?
|Explanation=This patient is suffering from fatigue, constipation, cold intolerance, and decreased concentration which are all suggestive of hypothyroidism. A positive test for [[antimicrosomal antibody|antithyroid peroxidase antibodies]] (anti-thyroid antibodies or anti-TPO) is highly specific for [[Hashimoto's thyroiditis]] (chronic lymphocytic thyroiditis). Hashimoto's thyroiditis is the most common cause of hypothyroidism that affects women in the majority of cases. It is an autoimmune chronic disease that is characterized by the presence of antibodies (anti-thyroid antibodies and anti-thyroglobulin antibodies) that destroy the follicles of the thyroid. Affected patients may show signs of hyperthyroidism early in the disease course, as thyroid hormones are released from disrupted follicles. However, patients eventually proceed to a hypothyroid state. On physical examination, patients often have a moderately enlarged, non-tender thyroid. Typically, laboratory findings in Hashimoto's thyroiditis reveal signs of hypothyroidism, namely elevated TSH with decreased concentrations of free T3 and T4. On histology, the thyroid gland reveals follicular atrophy, patchy lymphoid infiltrates with germinal centers, and presence of Hurthle cells. HLA-DR5 serotype. [[Hashimoto's thyroiditis]] is associated with an increased risk of thyroid [[lymphoma]]. These malignancies are typically non–Hodgkin's B-cell lymphomas (non-Hodgkin's lymphoma) and predominantly affect female patients over 70 years of age. Patients with Hashimoto's thyroiditis who have thyroid nodules on physical examination are usually requested to undergo fine needle aspiration (FNA) to rule out malignancies.
|AnswerA=Papillary carcinoma of the thyroid
|AnswerAExp=This patient has Hashimoto’s thyroiditis, which does not typically increase the risk of developing papillary carcinoma of the thyroid. Papillary carcinoma of the thyroid is the most common thyroid cancer. It may be associated with ''BRAF V600E'' mutations that may now be treated with vemurafenib. Other genetic alterations involve ''NRAS'' point mutation and RET translocation.
|AnswerB=Follicular carcinoma of the thyroid
|AnswerBExp=Hashimoto's thyroiditis does not usually increase the risk of developing follicular carcinoma of the thyroid. Follicular thyroid carcinoma is associated with a good prognosis and may be associated with ''RAS'' mutations.
|AnswerC=Medullary carcinoma of the thyroid
|AnswerCExp=[[Medullary carcinoma]] of the thyroid is associated with Multiple Endocrine Neoplasia type II A and B (MEN2A and MEN2B), but not with Hashimoto's thyroiditis.
|AnswerD=Non-Hodgkin's lymphoma
|AnswerDExp=Thyroid lymphomas are associated with [[Hashimoto's thyroiditis]].
|AnswerE=Anaplastic carcinoma of the thyroid
|AnswerEExp=Hashimoto's thyroiditis does not usually increase the risk of developing anaplastic carcinoma of the thyroid. These tumors carry a poor prognosis and tend to occur in older patients.
|EducationalObjectives=[[Hashimoto's thyroiditis]] is an autoimmune thyroid disease characterized by the presence of anti-thyroid peroxidase antibodies. It is associated with an increased risk of thyroid non-Hodgkin's lymphomas.
|References=Ali SM, He J, Carson W, et al. Extended antitumor response of a BRAF V600E papillary thyroid carcinoma t vemurafenib. Case Rep Oncol. 2014;7(2):343-8.<br>
First Aid 2014 page 323
|RightAnswer=D
|WBRKeyword=Autoimmune, Thyroid, Thyroiditis, Cancer, Hashimoto's thryoiditis, Endocrinology, Lymphoma, Non-Hodgkin's lymphoma, Non-Hodgkin lymphoma, Chronic lymphocytic thyroiditis, Lymphocytic thyroiditis
|Approved=Yes
}}