Hyperplasia

The Pathology Dictionary Team
February 24, 2023

What does hyperplasia mean?

Hyperplasia is a non-cancerous change that means an increased number of cells compared to normal. This change can only be seen when the tissue sample is examined under the microscope. Another word for hyperplasia is hyperplastic.

Types of hyperplasia

Hyperplasia can start anywhere in the body. In some parts of the body, this change is given a special name. The name may describe the types of cells normally found in that location, the shape of the tissue, or the look of the cells when examined under the microscope.

Common types of hyperplasia include:

• Breast – Usual ductal hyperplasia.
• Colon – Hyperplastic polyp.
• Endometrium – Endometrial hyperplasia without atypia.

Is hyperplasia a type of cancer?

Hyperplasia is not a type of cancer. However, some types are considered pre-cancerous conditions that can turn into cancer over time.  Pre-cancerous types are usually made up of abnormal-looking cells. Pathologists call these cells atypical.

Common types of hyperplasia with abnormal cells:

• Breast – Atypical ductal hyperplasia.
• Breast – Atypical lobular hyperplasia.
• Endometrium – Atypical endometrial hyperplasia.

What causes hyperplasia?

The cause depends on the area of the body involved. For example, this change is caused by long-term exposure to hormones in the breast, endometrium, and prostate. In the colon, this change is caused by physical stress and pressure inside the colon.

What is the difference between hyperplasia and hypertrophy?

Hyperplasia and hypertrophy both cause the tissue to increase in size. However, unlike hyperplasia, hypertrophy is associated with an increase in the size of each cell and not an increase in the number of cells.