Endocrine Pathology Case Studies


CASE 1: Papillary Carcinoma of Thyroid


Clinical History:

A 23-year-old woman has noted a slowly enlarging neck mass for the past 2 years. On physical examination she is found to have a single firm non-tender nodule that appears to be within the right lobe of the thyroid gland. Laboratory studies reveal a serum T4 of 7.2 micrograms/dl (normal 4.8 to 11.2) with TSH of 2.3 mU/mL. Her serum calcitonin is not elevated. An ultrasound examination of her neck suggests a solid mass, while a thyroid scintillation scan reveals decreased uptake within the nodule (a so-called "cold" nodule). She is taken to surgery.
  1. What criteria do you use to determine if the neoplasm is benign or malignant?

    2. Metastases and invasion are the best indicators. In endocrine tumors, cellular anaplasia is less reliable.

  2. What is the diagnosis?

    3. This is a papillary carcinoma. All papillary neoplasms of the thyroid are considered to be malignant. Note the papillations grossly evident in image 1.1. There is a psammomma body seen with image 1.2, and the papillary pattern is microscopically evident. In image 1.3 can be seen the clear nuclei typical for a papillary carcinoma of thyroid.

  3. What is the probable biologic behaviour of this lesion?

    4. Papillary carcinomas of thyroid tend to be indolent, even when metastatic. They can be multifocal. They tend to metastasize to cervical lymph nodes, and an enlarged node may be the first evidence for this disease.

  4. What are the four major types of thyroid carcinoma?

    5. These are papillary, follicular, medullary, and anaplastic. How do they differ microscopically? Papillary carcinomas have a branching, tree-like pattern, prominent clear nuclei, and psammoma bodies. Follicular carcinomas have follicles and lack the features of papillary carcinoma. Medullary carcinomas have polygonal cells in sheets and nests with a prominent amyloid stroma (and they like to make calcitonin). Anaplastic (undifferentiated) carcinomas are very pleomorphic (spindle cells, giant cells, small cells) and are very bad.