Melasma or just pigmentation? how to tell, and why it matters

Nearly everyone who comes in with brown patches calls it pigmentation. That one word covers at least four different things, and they don’t behave the same way. Melasma is the awkward one: hormones and heat drive it as much as sun does, and it sits deeper than it looks. Sun spots, freckles and the marks acne leaves behind are shallower and more predictable. Knowing which one you’re looking at changes everything that follows. And because an early melanoma can look like an ordinary brown spot, a skin check comes before any laser or light treatment, not after.

Is it melasma, or something else?

Melasma turns up as brownish patches with soft edges, usually mirrored across both cheeks, over the forehead, or above the top lip. It doesn’t flake. It almost always leaves the eyelids untouched. Most people I see with it are women somewhere between their twenties and forties, and it often starts around a pregnancy or a change in hormonal medication.

The others are easier to place, and you can usually tell them apart yourself.

Sun spots, or solar lentigines if your GP writes it down, are separate flat brown spots with a clean edge. Face, backs of the hands, forearms, chest. Decades of Brisbane sun, one spot at a time.

Freckles you’ve had since you were a kid. They darken over summer, fade off through winter, and they run in families.

Marks left by acne are the other common one. Eczema, a burn or a reaction to a product do the same thing. The giveaway is the shape: they sit exactly where the spot or the rash was.

Melanoma is the one that isn’t a cosmetic concern at all. A single patch that’s changing, spreading, or going darker in one part and not another needs checking. Early ones are flat and brown and can pass for an ordinary sun spot for years, which is why the section below exists.

Tap to enlarge

What’s going on under the patch?

For years melasma got filed under overactive pigment cells. The biopsy work of the last decade says it’s messier than that. Six things are going on at once.

• The pigment cells are bigger, busier, and making more than the skin beside them.
• The cells around them keep egging them on, in response to sun, to daylight through a window, and to heat.
• The thin layer separating the top of your skin from the living part underneath is damaged, so pigment leaks down into it.
• There are more blood vessels than usual in the patch, and they keep the whole thing ticking over.
• Inflammation sits in the background, pushing pigment production along.
• The deeper tissue shows the wear of long-term sun, the same changes we see in ageing skin.

Tap to enlarge

That difference is the reason melasma comes back and a sun spot doesn’t. It also explains why melasma has good months and bad months while a sun spot just sits there.

Why does it matter which one it is?

Because they don’t respond to the same things. A sun spot is a sitting target: the pigment is concentrated, it’s near the surface, and the skin around it isn’t looking for an excuse to react.

Melasma isn’t sitting still. The pigment cells are already switched on and the inflammation is already there, so it can react badly to things a sun spot shrugs off. Getting that wrong is how people end up with a patch darker than the one they started with, and it’s harder to undo than it was to cause. Deeper skin tones carry more of that risk.

Plenty of people have melasma and sun damage on the same face, and the two need to be told apart before anything else happens. That’s what a consultation is for. At our Newstead clinic it starts with your history and VISIA imaging, so we’re working from what your skin is actually doing rather than from a guess.

Could it be something more serious?

This is the part I won’t skip over. The type that mimics a sun spot on the face has a name, lentigo maligna, and it can sit on a cheek for a decade while everyone treats it as sun damage. It is slow, it is flat, and it is easy to dismiss.

Queensland has the highest rate of invasive melanoma in the world. If you grew up here, or you’ve spent twenty summers here, the odds are simply different for you than for someone reading this in London.

Here’s why it matters before any treatment rather than after. If a laser or IPL is used on a mark that turns out to be a melanoma, the pigment goes and the cancer stays. Worse, the thing a pathologist needs to look at has been altered, so the diagnosis can be missed or pushed back by years. In one hospital series of eleven people whose melanoma was found in a spot that had already been lasered, the gap between the laser and the diagnosis ran from under a year to ten years. That is not a small delay in a disease where timing is most of the outcome.

So the order matters. Have a full skin check with a skin cancer GP or a dermatologist before anyone treats pigment on your face or body. Bring anything that has changed shape, size or colour, anything that looks different from the marks around it, and anything new that has turned up after forty. Once you have the all clear, the cosmetic conversation can start.

Why is it worse in Brisbane?

We get a high UV index for most of the year rather than for a season, and it stays bright under cloud. It’s not the beach days that keep pigmentation going. It’s the walk between meetings in the Brisbane CBD, five days a week, for twenty years.

Heat matters too, which catches people out. A Brisbane summer works on melasma even in the shade, and daylight through a car window on the commute quietly does its bit on your right cheek.

So brown patches on a Brisbane face are usually more than one thing at once. We’re in Newstead, a few minutes north of the CBD. Come in and we’ll work out what yours are, and what that means for you. Read more about melasma and pigmentation, or book an initial consultation.

Where this comes from

Most of the above is what I see in clinic here in Brisbane. The parts that aren’t are these.