A cyst sits in the skin and often has a tiny dark dot in the middle. It feels firm, like a marble, and it can turn red and sore if it bursts. A lipoma is a soft, squishy lump under the skin that moves when you press it and rarely hurts. Neither one is dangerous, and neither needs removing unless it bothers you, gets in the way, or is changing.
| The difference | Epidermoid Cyst | Lipoma |
|---|---|---|
| What is inside | Keratin | Fat |
| How it feels | Firm, like a marble | Soft and doughy |
| Does it hurt | Only if it ruptures | Usually not |
The tiny dark opening in the centre is the punctum — the follicle the sac originally grew from. It is the single most useful feature on this page, and it is easy to miss unless you look closely in good light. Note also how defined the edges are: a cyst feels like a marble under the skin.
A lipoma sits under the skin rather than in it, so the surface stays completely normal — no dot, no colour change, no defined border. The skin slides freely over the top, which is the quickest way to tell it from a cyst without touching anything else.
Side by side
Epidermoid Cyst
Keratin
The protein your skin and nails are made of, packed into a closed sac that grew from a hair follicle.
Lipoma
Fat
Ordinary fat cells in a thin capsule. It is a benign growth, not a blockage.
Epidermoid Cyst
Firm, like a marble
The edges are clear. It rolls under your finger.
Lipoma
Soft and doughy
It gives when you press it. The edges are vaguer.
Epidermoid Cyst
No — it moves with the lump
The sac is attached to the skin.
Lipoma
Yes — freely
The lump sits below, so the skin glides over the top.
Epidermoid Cyst
Often a tiny dark dot
A small opening in the centre, called a punctum. It is the old follicle, and it is close to a giveaway.
Lipoma
Nothing
Normal skin, no opening.
Epidermoid Cyst
Face, neck, upper back, scalp
Also behind the ears.
Lipoma
Shoulders, back, arms, neck, thighs
Anywhere with a layer of fat.
Epidermoid Cyst
Millimetres to a few centimetres
Slow. It can flare and shrink if it ruptures.
Lipoma
Usually a few centimetres
Very slow, often stable for years.
Epidermoid Cyst
Only if it ruptures
Then it turns red, hot and painful within a day or two.
Lipoma
Usually not
A rare type called an angiolipoma is tender.
Epidermoid Cyst
Yes
A ruptured cyst leaks keratin into the tissue around it, and the body reacts. It looks exactly like an infection, and often is not one.
Lipoma
No
There is nothing to rupture or block.
Epidermoid Cyst
The whole sac, in one piece
Local anaesthetic, done when the lump is calm rather than inflamed. Any sac left behind will refill.
Lipoma
The lump and its capsule
Local anaesthetic. Straightforward, and it rarely comes back.
Lipoma
There is nothing to squeeze on a lipoma. It is solid fat, not a pocket.
Common questions