Lipomas vs. Cysts: What’s the Difference?

Lumps and bumps under your skin can definitely raise an alarm, but fortunately, most aren’t associated with a serious medical problem. Often, the culprit is something much more benign — a harmless cyst or a fatty lipoma.

While both cysts and lipomas may appear similar under your skin, they have different causes and different treatments, too. In this post, Michael H. Tarlowe, MD, offers a quick comparison of lipomas and cysts so you can understand their differences.

Lipoma basics

A lipoma is a collection of fat cells that group together, forming a lump between tissues — usually your skin and underlying muscle. Sometimes called a fatty tumor, lipomas are almost always benign, although in rare cases, they can develop into a type of cancer called a liposarcoma. 

Symptoms of lipomas

Lipomas under your skin typically feel soft or “squishy,” and if you gently press on a lipoma, it tends to move slightly. Lipomas rarely cause pain unless they press on nerves or they’re located near a joint or pressure point. 

Sometimes, lipomas form inside your body. In these instances, they can cause different symptoms depending on where they’re located and whether or not they affect an organ or other part of your body.

Causes of lipomas

Researchers aren't sure why lipomas form, but they do know they often run in families. Most lipomas appear during middle age — typically between 40-60 years of age — but they can form at other times, too. 

Quick facts about cysts

A cyst is a sac that’s filled with pus, fluid, or other substances, like hair or skin. Like lipomas, cysts are benign — noncancerous — and they can form inside your body as well as under your skin.

Symptoms of cysts

While lipomas feel soft or squishy, cysts are typically harder and feel firm to the touch. Like lipomas, cysts can vary in size and their growth rate can also vary. 

Many cysts cause no symptoms, but when they’re large or they’re located near a joint or nerve, they can cause pain or tenderness, swelling, and redness. They can also cause significant pain if they’re infected.

Causes of cysts

Cysts form for a variety of reasons, including clogged oil glands, infections, inflammation, and injuries. Pilonidal cysts form at the base of your tailbone, typically when one or more hairs become trapped inside your skin.

Diagnosis and treatment

Diagnosing cysts and lipomas typically begins with a physical exam and sometimes followed by imaging tests. In some instances, and depending on the location of the lump, Dr. Tarlowe performs a biopsy to obtain a small sample of tissue or fluid that’s examined under a microscope. Biopsies help diagnose cancer and infections and guide their treatment.

For both cysts and lipomas, Dr. Tarlowe usually only recommends treatment if the lump is causing symptoms, like pain, if it’s growing larger, or if there’s an infection. For infections, Dr. Tarlowe usually needs to drain it which can typically be done in the office under local anesthesia.

Symptomatic lipomas

If a lipoma causes pain or other symptoms, Dr. Tarlowe removes it surgically. During the procedure, he makes a small incision over the lipoma and removes all the fatty material. When a lipoma is near a nerve or joint, he may recommend removal even if you aren’t experiencing symptoms in order to prevent complications later.

Symptomatic cysts

Cysts can also be removed surgically, particularly if there’s a risk of recurrence. Some cysts containing only fluid can be drained using a needle.

Have that lump examined

Lipomas and cysts are two possible causes of lumps and bumps on your body, but there can be other causes, too, like infections or tumors. Having any unusual lump or bump evaluated right away is important for making sure you get the right treatment as quickly as possible.

To find out what’s behind that lump or bump, call 954-210-7127 or request an appointment online with Dr. Tarlowe at our office in Deerfield Beach, Florida.