1. Endocrine Pathology, Case 3 55-year-old woman presents for an annual physical exam. A painless 2.5 cm nodule is palpated in the left thyroid gland. There is an enlarged, nontender 2cm left cervical lymph node.

2. Identify the organ Describe the gross findings

3. Papillary carcinoma The surgical specimen consists of a bisected thyroid lobe which contains a solitary nodule (arrow) with irregular margins. The nodule is a papillary carcinoma.

4. Section from the thyroid nodule. Describe the histologic findings

5. Thyroid: Papillary carcinoma A microscopic section of a thyroid nodule reveals a papillary carcinoma. The neoplasm is composed of papillary structures intermixed with small follicles. A – Papillary structure B – Small follicle

6. Describe the high power histologic findings A microscopic section of a papillary carcinoma reveals a change in the epithelial nuclei referred to as "Orphan Annie eyes". The nuclei seem large with clear centers and distinct nuclear membranes.

7. Describe the histologic findings. Thyroid: Papillary carcinoma A microscopic section of a papillary carcinoma reveals psammoma bodies (arrow) which contain a dark blue to purple calcification.