Skin cancer, malignant tumors of the skin. The most common types of skin cancer are basal cell carcinoma, squamous cell carcinoma and melanoma. The less common forms include mycosis fungoides (a type of lymphoma) and Kaposi's sarcoma.
Overexposure to the sun is the main cause of the common skin cancers, and the popularity of tanning since the 1930s lies behind the rise in skin cancers. Depletion of the land of the protective ozone layer also plays a role. The most effective way to prevent skin cancer is to avoid exposure to the sun's ultraviolet rays are applied by the effective sunscreens (see sunburn) and use protective clothing.
Basal and squamous cell carcinomas
Basal and squamous cell carcinomas are the most common types of cancer. Both are derived from epithelial tissue (see epithelium). Are rare in people with dark skin, light-skinned, blue-eyed people who are not so well, but who have had significant exposure to the sun's rays are at greater risk. Both types usually occur on the face or other exposed areas.
Basal cell carcinoma is usually seen as a raised, sometimes ulcerous nodule. The nodules may look pearly. It grows slowly and rarely metastatic (spreads), but can be locally destructive and disfiguring. Squamous cell carcinoma is usually seen as a painless lump that grows on a wartlike injury, or that may arise in the patches of red, scaly sun-damaged skin called actinic Keratoses. Can metastasize and can lead to death.
Basal and squamous cell carcinomas are easily cured with proper treatment. The lesions are usually removed by scalpal excision, curettage, cryosurgery (freezing) or micrographic surgery in which successive thin slices are removed and the cancer cells to examine under a microscope until the samples are clear. If cancer is in an area where it would be difficult or disfiguring surgery, radiation therapy may be employed. Genetic scientists have discovered a gene that when mutated, causes basal cell carcinoma.
Melanoma
Melanoma is the most virulent type of skin cancer and the most likely to be fatal. In common with other skin cancers, melanoma can be caused by sun exposure, and its incidence is increasing throughout the world. There also appears to be a hereditary factor in some cases. Although people with fair skin are most susceptible, melanomas are also seen in dark-skinned people. Melanomas arise in melanocytes, the cells that contain melanin in the epidermal layer of skin. Melanin is the pigment that gives skin color and helps protect the skin against sun damage. Considering skinned people, melanomas appear most frequently on the trunk in men and in the arms or legs in women.
Black melanomas appear most frequently on the hands and feet. It is unknown whether blacks in melanoma is related to sun exposure. It is recommended that people examine themselves regularly for any evidence of characteristic changes in a mole that could raise a suspicion of melanoma. These include the asymmetry of the mole, a mottled appearance (variations in color shades of brown to a bluish tone), irregular or notched borders, and oozing or bleeding or a change in texture. Performed before surgery melanoma has spread is the only effective treatment for melanoma.
Basal and squamous cell carcinomas are the most common types of cancer. Both are derived from epithelial tissue (see epithelium). Are rare in people with dark skin, light-skinned, blue-eyed people who are not so well, but who have had significant exposure to the sun's rays are at greater risk. Both types usually occur on the face or other exposed areas.
Basal cell carcinoma is usually seen as a raised, sometimes ulcerous nodule. The nodules may look pearly. It grows slowly and rarely metastatic (spreads), but can be locally destructive and disfiguring. Squamous cell carcinoma is usually seen as a painless lump that grows on a wartlike injury, or that may arise in the patches of red, scaly sun-damaged skin called actinic Keratoses. Can metastasize and can lead to death.
Basal and squamous cell carcinomas are easily cured with proper treatment. The lesions are usually removed by scalpal excision, curettage, cryosurgery (freezing) or micrographic surgery in which successive thin slices are removed and the cancer cells to examine under a microscope until the samples are clear. If cancer is in an area where it would be difficult or disfiguring surgery, radiation therapy may be employed. Genetic scientists have discovered a gene that when mutated, causes basal cell carcinoma.
Melanoma
Melanoma is the most virulent type of skin cancer and the most likely to be fatal. In common with other skin cancers, melanoma can be caused by sun exposure, and its incidence is increasing throughout the world. There also appears to be a hereditary factor in some cases. Although people with fair skin are most susceptible, melanomas are also seen in dark-skinned people. Melanomas arise in melanocytes, the cells that contain melanin in the epidermal layer of skin. Melanin is the pigment that gives skin color and helps protect the skin against sun damage. Considering skinned people, melanomas appear most frequently on the trunk in men and in the arms or legs in women.
Black melanomas appear most frequently on the hands and feet. It is unknown whether blacks in melanoma is related to sun exposure. It is recommended that people examine themselves regularly for any evidence of characteristic changes in a mole that could raise a suspicion of melanoma. These include the asymmetry of the mole, a mottled appearance (variations in color shades of brown to a bluish tone), irregular or notched borders, and oozing or bleeding or a change in texture. Performed before surgery melanoma has spread is the only effective treatment for melanoma.
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