Malignant Melanomas are the most unpredictable of the three malignant types described here. They have can spread to other areas of the body via the lymphatics and the blood vessels. They sometimes arise from pre-existing freckles, or from new. They are characterised by a flat and dark pigmented appearance – they may be variegated (different intensity of pigment within the same lesion), and they grow both horizontally and in thickness. They may bleed. Early detection and removal is essential, as it is the thickness of the lesion which dictates its propensity too spread. Metastasis (distant spread) can be fatal.
If you have a new pigmented lesion, or one that is growing and changing, you should consult an expert immediately. This is a situation where procrastination and denial is a very dangerous plan of action.
The lesion on the left is a Lentigo Maligna which is a pre-cancerous state.
On the right there is a Malignant Melanoma which is altogether darker and thicker.
Both should be excised.