Oncocytic

by Jason Wasserman MD PhD FRCPC
April 27, 2022

What does oncocytic mean?

Pathologists use the term oncocytic to describe cells that look bright pink when stained with hematoxylin and eosin (H&E) and examined under a microscope. Oncocytic cells look pink because the cytoplasm (body) of the cell is full of mitochondria that stick to eosin (a pink dye).

A tumour made up entirely of oncocytic cells.

Where are oncocytic cells normally found?

Oncocytic cells can be found in many different types of organs and tissues throughout the body. Cells that are not normally oncocytic can also become oncocytic over time. Pathologists call this oncocytic metaplasia. Oncocytic cells in the thyroid gland are commonly called Hurthle cells. In the thyroid gland, pathologists use the term oncocytic metaplasia or Hurthle cell metaplasia to describe follicular thyroid cells that have changed into oncocytic cells.

What types of tumours are made up of oncocytic cells?

A non-cancerous tumour made up entirely of oncocytic cells is called an oncocytoma. This type of tumour is commonly found in the kidneys and the salivary glands although it can also be found in other locations in the body. A cancerous tumour made up entirely of oncocytic cells is called an oncocytic carcinoma. Most oncocytic carcinomas start in the head and neck from one of the salivary glands such as the parotid gland or submandibular gland. Hurthle cell carcinoma is a special name given to an oncocytic carcinoma that starts in the thyroid gland.