There are four main types of melanomas: superficial spreading, lentigo malinga, acral lentiginous and nodular. The first three types discussed here tend to occupy only the top layers of the skin. In some instances, however, they become invasive and spread deeper into the body. The last type of melanoma starts as an invasive cancer. By the time it is detected, it has already gone deeper into the skin and may have spread to other parts of the body. Because all forms of melanoma have the potential to become invasive, it is important that any signs and symptoms of melanoma are reported to your doctor immediately.
The most frequently occurring type of melanoma is superficial spreading melanoma, which accounts for roughly 70% of all cases. This type of melanoma tends to grow outwards on the epidermis, the top layer of skin, rather than growing into the deeper layers of the skin. Superficial spreading melanoma is most common in middle-aged people, but it is also the form of melanoma most frequently diagnosed in young people. In people of all ages, it tends to occur on the legs in women, trunk in men, and the upper back in both genders. The melanoma can occur in a mole or it may arise spontaneously. It usually appears as a flat, asymmetrical, and discolored lesion with irregular borders.
|Type of melanoma||Percentage of cases||Group of people most affected||Location on body|
|Superficial spreading||70%||Middle aged white people||Upper back, legs, and trunk|
|Lentigo maligna||10%||Elderly white people||Face, ears, arms, and upper trunk|
|Acral lentiginous||2 – 3 %||African Americans and Asians||Soles of feet, near big toenail, and palms of hands|
|Nodular||10 – 15% of cases||Elderly white people||Trunk, legs, arms, and scalp|
Lengtigo maligna also tends to grow on the skin’s surface for a relatively long time before spreading into the deeper layers. The lesion is usually flat or slightly raised and a mottled tan, brown, or dark brown in color. This type of melanoma is most often diagnosed in the elderly on areas of the body that have received heavy sun exposure, such as the face, ears, check, upper back, and arms. Until the lesion becomes invasive, it is simply referred to as “lentigo maligna.” Once it spreads to the deeper layers, lentigo maligna melanoma will be diagnosed.
This rare form of melanoma is usually found on the soles of the feet and under or around the big toenail, but it can also occur on the palms of the hands. Like the other types mentioned above, acral lentiginous melanoma spreads across the skin’s surface before penetrating the deeper layers of the skin. This is the most common form of melanoma among African-Americans and Asians, and is the least frequently diagnosed type in Caucasians.
Unlike the previous three types discussed, nodular melanoma is almost always invasive and has usually penetrated the deeper layers of the skin at the time of diagnosis. This form of melanoma develops quickly and is recognized as a malignancy when a bump develops. The bump is usually black, but may also be gray, white, blue, brown, tan, red, or the same color as surrounding skin. It is most frequently seen in elderly people, where it develops on the trunk, legs, arms, or scalp. The most aggressive form of melanoma, nodular melanoma requires immediate treatment and extensive testing to determine if the cancer has spread to other parts of the body.
Click here or Call 212.321.0032 to schedule an appointment