Lipomas and cysts share many similarities, starting with the fact that they’re two of the most common benign subcutaneous skin growths — or noncancerous lumps that develop just beneath the skin. It makes sense that people often confuse the two since both are typically:
But outside of their frequent rate of occurrence, harmless nature, and similar external qualities, these abnormal skin bumps differ in several specific ways.
As a board-certified general surgeon who specializes in minimally invasive lipoma and cyst removal at Precision Surgery and Advanced Vein Therapy in Glendale, Arizona, Dr. Johnny Serrano is here to set the record straight on these similar — yet very different — growths.
Situated in the subcutaneous fat layer between your skin and muscle tissues, a lipoma is an abnormal mass of fat cells that are encased in a round, fibrous capsule. As this collection of fat cells gradually increases, the lipoma it creates pushes outward to form a noticeable lump.
While there are various lipoma subtypes, the average lipoma:
If a lipoma does get larger over time (and many do not), it does so very slowly. Most lipomas tend to stabilize when they’re no more than two inches in diameter.
While lipomas can develop on any area of the body where there are fat cells, typical lipoma sites include the shoulders, neck, forehead, back, abdomen, arms, or thighs. These fatty growths appear most often in middle-aged adults.
Skin cysts, also known as epidermoid cysts, develop when surface skin cells (epidermal cells) don’t shed normally. As these errant cells migrate to deeper skin layers, they multiply and trigger the formation of an enclosed sac — or cyst.
Once a cyst sac has formed, the errant skin cells inside it begin to actively secrete keratin, an essential skin protein with an oily texture. As keratin slowly builds up in the sac, it condenses into a thick, yellowish paste that engorges the cyst — sometimes to the point of eruption, much like a pimple. The average skin cyst:
Skin cysts can appear anywhere but are most likely to form on the face, neck, and torso. While anyone can get them after puberty, they’re most common in young and middle-aged adults.
Various other types of cysts can appear on the skin, including pilonidal cysts, pilar cysts, and sebaceous cysts. These cysts often contain keratin along with other substances. A pilonidal cyst, for example, which typically develops along the buttocks crease following a skin infection from an ingrown hair, may also contain fluid and air.
Another thing that lipomas and cysts have in common is that most of them are relatively inconspicuous and don’t require medical care or attention of any kind, apart from watchful waiting to see if they change or grow.
There are, of course, exceptions in both cases. Let’s take a closer look at when lipomas and cysts require treatment:
Since lipomas don’t pose an infection risk, treatment is only necessary when a lipoma is uncomfortably large, prominent, or difficult to conceal; frequently irritated by clothing or activity; or in a highly unusual spot, such as the forehead or the palm of the hand.
In all cases, lipoma treatment means minimally invasive surgery. To remove a simple lipoma, Dr. Serrano numbs the area, makes a tiny incision, and gently squeezes out the self-contained lipoma capsule. He may need to excise larger lipomas or lipomas that have blood vessels in sections.
All pilonidal cysts require surgical removal as a preventive measure simply because they’re so prone to infection. A skin cyst that shows signs of infection — one that’s sore, swollen, red, or oozing foul-smelling pus — requires urgent medical treatment to clear the infection.
Minimally invasive cyst removal is often the best option for cysts that grow quickly, cause discomfort, are easily irritated, are prominent or hard to hide, or are in a bothersome location, such as between the fingers.
Do you have a suspected lipoma or cyst that requires evaluation? Our board-certified general surgeon in Glendale, Arizona, can help. Call 623-321-5663 or click online to schedule a visit with Dr. Serrano at Precision Surgery and Advanced Vein Therapy today.
