Risks of Sun OverexposureLuz Pedroza Duque
Risks of Sun Overexposure is defined as a UVR dose sufficient to cause erythema, should be avoided. Repeated overexposure is believed to cause eye and skin injury and allergic reactions and increase the risks of developing photo aging of the skin, dryness, wrinkling, and (sometimes fatal) skin cancer.
Skin cancers can be divided into two main categories (melanoma and non-melanoma) and three main types (Basal Cell Carcinoma, Squamous Cell Carcinoma, and Cutaneous Malignant Melanoma). Non-melanoma skin cancers are the most common skin cancers. Basal Cell /carcinoma and Squamous Cell Carcinoma are the two most common forms of non-melanoma skin cancers. Melanomas are cancers that develop from melanocytes.
1. Non-melanoma Skin Cancer
More than 1 million cases of Basal Cell or Squamous Cell cancer will be diagnosed annually. Men are twice as likely to develop non-melanoma cancers as women. Death is uncommon in these cancers. It is estimated that 1,000 to 2,000 people die each year from non-melanoma skin cancer.
Basal Cell Carcinoma (BCC) occurs in the deepest layer of the epidermis and it is named for the skin cell in which it arises. Affecting 800,000 Americans each year, Basal Cell Carcinoma is the most common form of skin cancer. About 70 to 80 percent of all skin cancers in men and 80 percent to 90 percent in women are Basal Cell Carcinomas. They occur most frequently on exposed parts of the bodyï¿½the face, ears, neck, scalp, shoulders and back.
Basal Cell Carcinoma is slow growing. It is rare for Basal Cell Carcinoma to spread to the lymph nodes or to distant parts of the body. If the cancer is not treated, however, it can grow into and invade the bone and tissue nearby.
After treatment, Basal Cell Carcinoma can recur. Thirty-five percent to 50 percent of people diagnosed with one Basal Cell cancer develop a new skin cancer within five years of the first diagnosis.
Signs: Basal Cell Carcinoma usually appears as a smooth, waxy or pearly bump that grows slowly and rarely spreads.
The squamous Cell Carcinoma (SCC) occurs in the upper layers of the epidermis. Afflicting more than 200,000 Americans each year, Squamous Cell Carcinoma is the second most common form of skin cancer. Squamous Cell Carcinomas account for about 10 percent to 30 percent of all skin cancers. Squamous Cell Carcinomas most commonly appear on exposed areas of the body (the face, ear, neck, lip, and back of the hands) but can occur on mucous membranes and all other areas of the body.
Squamous cell cancers tend to be more aggressive than basal cell cancers. Although it is uncommon, they are more likely to invade surrounding tissues, and slightly more likely to spread to lymph nodes or distant parts of the body
Sometimes squamous Cell Carcinoma causes a firm, nodular or flat growth with a crusted, ulcerated or scaly surface on the face, ears, neck hands or arms.
Cutaneous Malignant Melanoma (CMM) is rarer but is aggressive and can be fatal. It is estimated that in 2005 there will be 59,580 cases diagnosed and 7,770 deaths reported. Since 1981, the incidence of melanoma has increased a little less than 3 percent per year. The percentage of people who develop melanoma has more than doubled in the past 30 years. Malignant melanoma causes more than 75 percent of all deaths from skin cancer. Melanoma is the most common cancer among people 25 to 29 years old.
This disease can spread to other organs, most commonly the lungs and liver.