They are five, and all first growing radially (often for months and years) before eventually going deep. Only
nodular melanoma grows vertically right away. Hence, it lacks the typical ABCDE warning signs and presents
instead with elevation and/or ulceration/bleeding.
Superficial spreading melanoma: The most common subtype (>70% of cases) and the one most
frequently found near existing nevi. Onset is during the third to fifth decade, usually over the back of
men, legs of women, and trunk of both genders. Lesions are flat or slightly raised, brown, variegated
(with black, blue, pink, or white discoloration), >6 mm in diameter, and with irregular borders.
Nodular melanoma: 15–30% of all melanomas. It presents as a papule or dome-shaped nodule, on legs
and trunk, and black or brown-to-bluish in color, even though it may also be amelanotic. It often grows
rapidly over just a few months, often with ulceration and bleeding, especially after minor trauma. It
originates at the dermoepidermal junction, growing vertically into the dermis with little radial extension.
Lentigo maligna: An in situ (i.e., intraepithelial)precursor of lentigo maligna melanoma. This presents as a flat and relatively large (>3 cm) hyperpigmented area with variegated pigment and an irregular border, commonly located on sun-exposed areas, especially head, neck, and arms. Late occurring (fifth and sixth decades), it exists for 10–15 years before undergoing malignant transformation. This is nonetheless rare (estimated 5–8%) and usually heralded by new brown-to-black macular pigmentation or raised blue-black nodules. Growth is radial. Often called Hutchinson’s freckle from the English surgeon who also described the Hutchinson’s triad of congenital syphilis.
Lentigo maligna melanoma: 4–15% of all melanomas. Almost exclusive of sun-damaged areas
of the elderly. Large in size (>3 cm), it typically grows slowly over a period of many years. More
variegated in color than lentigo maligna.
Acrolentiginous melanoma: The rarest in whites (2– 8%), but the most common in dark-skinned groups
(African Americans, Asians, and Hispanics), in whom it accounts for 29–72% of all melanomas.
Because of delayed diagnosis, it carries a worse outcome. It occurs on palms, soles, or beneath the
nail plate, presenting as one or more dark papules against a pigmented and unevenly speckled
background—often resembling lentigo maligna melanoma. The subungual variety may occur as
diffuse nail discoloration, or a longitudinal pigmented band within the nail plate. A hallmark finding is
pigment spreading to proximal or lateral nail folds (Hutchinson’s sign).
nodular melanoma grows vertically right away. Hence, it lacks the typical ABCDE warning signs and presents
instead with elevation and/or ulceration/bleeding.
Superficial spreading melanoma: The most common subtype (>70% of cases) and the one most
frequently found near existing nevi. Onset is during the third to fifth decade, usually over the back of
men, legs of women, and trunk of both genders. Lesions are flat or slightly raised, brown, variegated
(with black, blue, pink, or white discoloration), >6 mm in diameter, and with irregular borders.
Nodular melanoma: 15–30% of all melanomas. It presents as a papule or dome-shaped nodule, on legs
and trunk, and black or brown-to-bluish in color, even though it may also be amelanotic. It often grows
rapidly over just a few months, often with ulceration and bleeding, especially after minor trauma. It
originates at the dermoepidermal junction, growing vertically into the dermis with little radial extension.
Lentigo maligna: An in situ (i.e., intraepithelial)precursor of lentigo maligna melanoma. This presents as a flat and relatively large (>3 cm) hyperpigmented area with variegated pigment and an irregular border, commonly located on sun-exposed areas, especially head, neck, and arms. Late occurring (fifth and sixth decades), it exists for 10–15 years before undergoing malignant transformation. This is nonetheless rare (estimated 5–8%) and usually heralded by new brown-to-black macular pigmentation or raised blue-black nodules. Growth is radial. Often called Hutchinson’s freckle from the English surgeon who also described the Hutchinson’s triad of congenital syphilis.
Lentigo maligna melanoma: 4–15% of all melanomas. Almost exclusive of sun-damaged areas
of the elderly. Large in size (>3 cm), it typically grows slowly over a period of many years. More
variegated in color than lentigo maligna.
Acrolentiginous melanoma: The rarest in whites (2– 8%), but the most common in dark-skinned groups
(African Americans, Asians, and Hispanics), in whom it accounts for 29–72% of all melanomas.
Because of delayed diagnosis, it carries a worse outcome. It occurs on palms, soles, or beneath the
nail plate, presenting as one or more dark papules against a pigmented and unevenly speckled
background—often resembling lentigo maligna melanoma. The subungual variety may occur as
diffuse nail discoloration, or a longitudinal pigmented band within the nail plate. A hallmark finding is
pigment spreading to proximal or lateral nail folds (Hutchinson’s sign).