Cysts

What are cysts?

A cyst is a benign, or non-cancerous, closed collection of tissue that is filled with fluid, pus, or other material such as blood, joint fluid, cerebrospinal fluid, etc. Cysts may be found anywhere in the body, and may be a congenital or acquired condition.

Depending on where in the body a cyst is found, and the mechanism of its formation, a cyst will be called different names:

• Bone cyst
• cysts from infections
• dermoid cyst
• ganglion cyst
• sebaceous cyst
• epidermal cyst
• lung cyst
• kidney cyst
• arachnoid cyst in the brain, etc.

What causes cysts?

Cysts develop from a variety of causes, and may be large or small. 

What are the symptoms of cysts?

Depending on area involved, the size, and the cause of the cyst, symptoms will vary from none to major.

What are cyst care options?

In many cases, no treatment may be needed. If treatment is required, there are a many options available to manage the cyst, depending on its position and size. 

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: September 16, 2025 12:16 PM