The most serious form of skin cancer.

Overview: Superficial spreading melanoma is the most common type of melanoma, accounting for about 70% of cases. It often begins as a dark brown or black spot that grows outward from a new mole or an existing one. It tends to appear on areas with significant sun exposure, especially skin that has been sunburned in the past.

Appearance: These lesions are usually larger than 6 mm and often exceed 10 mm in diameter. They tend to be irregular in shape, asymmetric, raised, and made up of several colours. They are most commonly found on the torso in men, the legs in women, and the upper back in both.

Dermoscopy Features: Lesions typically show a “chaotic” pattern, meaning more than one structure or colour is arranged asymmetrically. Common features include multiple colours, blue-grey areas, radial lines or segmental pseudopods, peripheral dots or clods, white lines, and varied vessel patterns.

Overview: Lentigo maligna melanoma often appears as a dark, unevenly coloured patch with an irregular border. It can resemble a large, irregular freckle and is most commonly seen on sun-exposed areas such as the face and arms, especially in older adults.

Appearance: These lesions are usually larger than 6 mm, with an irregular outline and a smooth surface. Their colour can vary—light brown, dark brown, pink, red, or white—and they tend to slowly expand over several years. Ulceration, bleeding, itching, or stinging may develop over time, along with increasing colour variation and thickening in parts of the lesion.

Dermoscopy Features: Common dermoscopic signs include brown or grey circles, multicoloured pigmentation, and light brown to black areas.

Overview: Nodular melanoma appears as a firm, dome-shaped bump, often black or dark brown. It grows more quickly than other melanoma types, moving from the epidermis into deeper layers of the skin and, in some cases, spreading to other parts of the body. It accounts for about 10% of all melanomas.

Appearance: These lesions typically present as a nodule or papule and may look symmetrical. Their colour can vary (tan, blue, red, or dark brown) and the surface may be smooth, rough, crusted, or warty. The tissue is often fragile and may bleed easily, though some lesions appear without symptoms. Nodular melanoma can develop anywhere but is most common on sun-exposed areas of the head and neck.

Dermoscopy Features: Dermoscopy may show a chaotic, multicoloured pattern with more than one structure or colour arranged asymmetrically. Helpful clues can include grey and blue areas, polarizing-specific white lines, and polymorphous vessels.

Overview: Desmoplastic melanoma is a rare form of melanoma that often develops on sun-damaged skin, particularly in older adults. It usually appears as a slow-growing lump that may look scar-like, firm, and uneven in colour.

Appearance: These lesions can range from medium to large and may present as a raised papule, nodule, or plaque. Borders are often indistinct, and the colour is typically skin-toned to pink. Some lesions may ulcerate, bleed, itch, or cause a stinging sensation.

Dermoscopy Features: Dermoscopy often shows structureless, scar-like areas with grey dots and shades of brown, tan, white, or milky red. Helpful clues can include regression structures with a scar-like appearance, white lines on polarized dermoscopy, and various vascular patterns such as serpentine or dotted vessels and milky red areas.

Overview: Acral lentiginous melanoma is an uncommon subtype that often looks like a persistent bruise or dark spot that doesn’t heal. It can develop on the palms, soles, or under the nails, where it may appear as a dark streak.

Appearance: Lesions range widely in size at diagnosis, from a few millimetres to several centimetres. Early on, they may be subtle patches or macules, but over time they become more irregular in shape and colour. Common colour patterns include brown, blue-grey, and red. These melanomas typically appear on the palms, soles, fingers, toes, or beneath the nails.

Dermoscopy Features: A parallel ridge pattern is characteristic, often with a chaotic, multicoloured appearance. Additional dermoscopic clues may include grey or blue structures, parallel or chaotic lines, peripheral black dots, or clods.

Overview: Subungual melanoma is a rare type of melanoma that develops under the fingernails or toenails. It’s often mistaken for a bruise, appearing as a dark brown or black mark. While it can occur in anyone, it is seen more often in individuals with darker skin tones.

Appearance: A new or changing pigmented band wider than 3 mm is a common early sign. The band may show parallel lines with varying colours, including brown, grey, yellow, or black. The nail surface may appear normal or show splitting or roughness as the lesion progresses. It can occur on any fingernail or toenail. These lesions are often painless at first but may ulcerate, bleed, or become painful if the deeper tissues or bone are affected.

Dermoscopy Features: Dermoscopy typically shows chaotic parallel lines with shades of grey and black.

Overview: uveal melanoma is a type of eye cancer that involves the choroid, ciliary body, and iris. The tumour develops from the melanocytes lying within the uveal region.