A cyst is a closed sac or pocket that forms beneath the skin or within the body, often filled with fluid or semi-solid material. Cysts can appear almost anywhere on the body, and they vary in size, texture, and cause. While cysts and lipomas may feel similar to the touch, they are different growths. A lipoma is a soft mass made of fatty tissue that sits under the skin, whereas a cyst contains a defined lining that encloses its contents. Lipomas tend to feel doughy and move easily, while cysts often feel firmer and may become tender if inflamed. Here are three common types of cysts and how to recognize them:
Sebaceous Cysts
Sebaceous cysts develop from the sebaceous glands, which produce the oil that lubricates skin and hair. These cysts commonly appear on the scalp, face, neck, and back. They typically contain a thick, oily substance and may have a small opening at the surface. Most sebaceous cysts grow slowly and remain painless unless they become infected or irritated.
Treatment often depends on the size and symptoms of the cyst. Smaller cysts may be monitored without intervention, but larger or bothersome ones can be removed through a minor surgical procedure. A general surgeon may drain the cyst or excise it entirely, but full removal of the sac lining helps reduce the chance of recurrence.
Epidermoid Cysts
Epidermoid cysts are among the most common types of skin cysts, and they are frequently confused with sebaceous cysts. These form when skin cells that should shed become trapped beneath the surface, creating a sac filled with keratin. They usually appear as small, round bumps on the face, neck, trunk, or shoulders and are generally slow-growing. Many epidermoid cysts cause no discomfort and require no treatment, but when a cyst becomes inflamed, ruptures, or grows large, a physician may recommend removal. In cases of infection, drainage and antibiotics may be necessary before surgical removal.
Baker’s Cysts
A Baker’s cyst, also known as a popliteal cyst, forms behind the knee. It develops when excess joint fluid collects in a sac at the back of the knee, often in connection with an underlying condition such as arthritis or a cartilage injury. This type of cyst can cause a feeling of tightness, swelling, or stiffness, particularly when bending or extending the leg. Treatment usually focuses on the underlying cause rather than the cyst alone, so care options may include:
- Managing the Joint Condition
- Draining Fluid From the Sac
- Surgical Intervention
Addressing the root problem often reduces the likelihood that the cyst will return.
When To Visit a Surgeon
While many cysts are harmless and remain stable over time, certain signs suggest it may be time to seek evaluation. A cyst that grows rapidly, becomes painful, changes in appearance, or shows signs of infection needs closer examination. If a bump or lump is limiting your movements or affecting your daily comfort, contact a surgeon for medical advice.
A general surgeon can assess the lump, determine its type, and recommend an appropriate course of action based on your situation. Attempting to squeeze or drain a cyst on your own can lead to infection or scarring, so professional care is the safest option. A medical professional can provide a proper assessment and discuss the treatment options that are appropriate for your needs.
