A 66-year-old woman comes to the physician because of a 3-month history of a painless lump on her neck. She says that the lump has gradually increased in size and is hard to the touch. Family history is unremarkable. She appears healthy. Examination shows a 2.5-cm (1-in) firm, irregular swelling on the left side of the neck that moves with swallowing. There is painless cervical lymphadenopathy. Ultrasound of the neck shows a solitary left lobe thyroid mass with increased vascularity and hypoechoic thyroid nodule . Fine-needle aspiration biopsy shows clusters of cells with large, overlapping nuclei containing finely dispersed chromatin. Numerous intranuclear inclusion bodies and grooves are also seen. Which of the following is the most likely diagnosis?

Question

A 66-year-old woman comes to the physician because of a 3-month history of a painless lump on her neck. She says that the lump has gradually increased in size and is hard to the touch. Family history is unremarkable. She appears healthy. Examination shows a 2.5-cm (1-in) firm, irregular swelling on the left side of the neck that moves with swallowing. There is painless cervical lymphadenopathy. Ultrasound of the neck shows a solitary left lobe thyroid mass with increased vascularity and hypoechoic thyroid nodule . Fine-needle aspiration biopsy shows clusters of cells with large, overlapping nuclei containing finely dispersed chromatin.  Numerous intranuclear inclusion bodies and grooves are also seen.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

Eductional Objective: Papillary thyroid carcinoma is the most common type of thyroid cancer.  Characteristic microscopic features include large cells with nuclei containing finely dispersed chromatin, giving them an empty or ground-glass appearance (ie, Orphan Annie eye), as well as intranuclear inclusions and nuclear grooves.

A 66-Year-Old Woman Comes to the Physician Because of a 3-Month