Melanoma
Melanoma is the most serious type of skin cancer. The most important message is simple: when melanoma is found early, treatment is usually straightforward and outcomes are excellent. When it’s found late, it can become life-threatening.
This page is a hub to help you understand the two most common “early” melanoma categories we diagnose and treat — and what they mean for your next steps.
Book a targeted spot check (1–3 spots)
Book a full skin check
Quick links
What is melanoma?
Melanoma starts in melanocytes (the pigment cells that give skin its colour). It often appears as:
- a new spot that looks different from your other moles (“the ugly duckling”), or
- a mole that changes (size, shape, colour), or
- a spot that becomes asymmetric, develops an irregular border, or shows multiple colours.
Not all melanomas are very dark. Some are pink, red, or skin-coloured — which is why change over time matters more than any single checklist.
If you’ve noticed a changing lesion, don’t monitor it for months. Get it assessed.
Book a targeted spot check (1–3 spots)
Why “in situ” vs “invasive” matters
When melanoma is diagnosed, one of the first questions is: has it started to invade deeper layers of skin?
- Melanoma in situ means abnormal melanoma cells are confined to the top layer of skin (the epidermis). It has not invaded deeper tissue.
- Thinly invasive melanoma means melanoma cells have entered deeper layers, but the invasion is still shallow. This is still considered early melanoma, and outcomes are usually very good — but management and follow-up can differ.
That’s why we separate melanoma into these two pages:
Melanoma in situ (very early melanoma)
Melanoma in situ is the earliest stage. Treatment is usually minor surgery to remove it with an appropriate safety margin, and ongoing surveillance.
Read more: Melanoma in situ
Thinly invasive melanoma (early invasive melanoma)
Thin melanomas have invaded beyond the surface layer, but only to a limited depth. Treatment is still usually surgical, and your follow-up plan may depend on the measured depth and other pathology features.
Read more: Thinly invasive melanoma
Not sure which one you have?
If you’ve been told you have “melanoma” but you’re unsure what type, we can explain your pathology report in plain English and map out the right follow-up plan.
Frequently Asked Questions
What’s the difference between melanoma in situ and thin melanoma?
In situ is confined to the top layer of skin. Thin melanoma has started to invade deeper layers, but only slightly. Both are usually highly treatable when managed early.
Should I book a spot check or a full skin check?
- Spot check: best if you have 1–3 specific lesions you’re worried about.
- Full skin check: best if you want reassurance, you’ve had previous skin cancer, you have many moles, or you’re high risk.
Do I need urgent review for a changing mole?
If a spot is changing quickly, looks different from your other moles, or is bleeding/crusting without explanation, it should be assessed promptly.
In situ is confined to the top layer of skin. Thin melanoma has started to invade deeper layers, but only slightly. Both are usually highly treatable when managed early.
- Spot check: best if you have 1–3 specific lesions you’re worried about.
- Full skin check: best if you want reassurance, you’ve had previous skin cancer, you have many moles, or you’re high risk.
If a spot is changing quickly, looks different from your other moles, or is bleeding/crusting without explanation, it should be assessed promptly.