What is Melanoma
I. Skin cancer is divided into 2 categories:
A. Non-melanoma skin cancer which is divided into 2 main types:
- Basal cell skin cancer
- Squamous cell skin cancer
B. Melanoma skin cancer which is divided into 5 subtypes:
- Superficial spreading melanoma (SSM)
- Nodular melanoma (NM)
- Acral lentiginous melanoma (ALM)
- Amelanotic melanoma (AM)
- Lentigo maligna melanoma (LMM)
Melanoma is one of the three types of skin cancer -- basal cell, squamous cell, and melanoma skin cancer. Skin cancer is divided into two subcategories: non-melanoma and melanoma. The non-melanoma skin cancers are called basal cell skin cancer and squamous cell skin cancer. They compose 95% of all skin cancers.
Melanoma skin cancer accounts for only 5% of all skin cancers but it has the greatest potential to spread to other parts of the body (metastasize) and therefore, the highest mortality.
Basal cell, squamous cell, and melanoma skin cancer each has a different appearance and course. It should be emphasized that with early detection and treatment 90% of all skin cancers are curable.
Melanoma grows primarily on the skin (cutaneous) but can also be found in the eye (ocular, uveal), in the mouth (oral), and in the genital rectal areas (vulvar, penile, anal). Once it has spread from its primary site, melanoma can be found in all the body's internal organs.
Appearance of melanoma generally occurs during middle age with 45 years being the peak onset, but with increased incidence, more young adults and even children are being diagnosed.
Melanoma skin cancer is then further divided into five main types -- superficial spreading melanoma (SSM), acral lentiginous melanoma (ALM), lentigo maligna melanoma (LLM), amelanotic melanoma (AM), and nodular melanoma (NM). These are further subdivided into vertical and radial (horizontal) growth categories. The first four start as growths in the epidermis (upper skin layer) initially confined within this site (in-situ) and spread horizontally allowing easier detection of skin/mole changes. The fifth type, nodular melanoma, has only a rapid vertical growth phase quickly spreading to the dermis (lower skin layer) where blood vessels may transport it to other areas of the body. It is considered the most aggressive, requiring early diagnosis.