Sunlight
How does the sun cause cancer?
What is Cancer?
Sunlight
How exposure affects the skin
-UVA penetrates deeply into the skin (the dermis) causing genetic damage to cells, photo-ageing (wrinkling, blotchiness etc) and immune-suppression.
UVB penetrates into the epidermis (top layer of the skin) causing damage to the cells.
-UVB is responsible for sunburn; a significant risk factor for skin cancer, especially melanoma.
UV radiation can damage the DNA, or genetic information, in skin cells, creating "misspellings" in their genetic code and, as a result, alter the function of those cells. If the body is unable to repair this damage the cell can begin to divide and grow in an uncontrolled way. This growth can eventually form a tumor which are either benign (noncancerous) or malignant (cancerous).
The main types of Skin Cancer caused by the Sun.
There are three main types of skin cancer: basal cell carcinoma, squamous cell carcinoma and melanoma. Basal cell and squamous cell cancers are less serious types and make up 95% of all skin cancers. Also referred to as non-melanoma skin cancers, they are highly curable when treated early. Melanoma ^^ , made up of abnormal skin pigment cells called melanocytes, is the most serious form of skin cancer and causes 75% of all skin cancer deaths. Left untreated, it can spread to other organs and is difficult to control.
How to detect and diagnose Skin Cancer
The cure rate for skin cancer could be 100 percent if all skin cancers were brought to a doctor's attention before they had a chance to spread. Therefore, people should check themselves regularly for new growths or other changes in the skin. Any new, colored growths or any changes in growths that are already present should be reported to a doctor without delay.
Skin Cancer - Diagnosis
Most skin cancer is diagnosed and treated in the same way. When an area of skin does not look normal, the doctor may remove all or part of the growth. This is called a biopsy. To check for cancer cells, the tissue is examined under a microscope by a pathologist or a dermatologist. A biopsy is the only sure way to tell if the problem is cancer.
Doctors generally divide skin cancer into two stages: local (affecting only the skin) or metastatic (spreading beyond the skin). Because skin cancer rarely spreads, a biopsy often is the only test needed to determine the stage.
Prevention of Skin Cancer
- Always wear sunscreen.
- Avoid the sun from 10 to 2.
- When in the sun, wear sunglasses that block UVA and UVB rays; and protective clothing (long-sleeved shirts, long pants). Dark, tightly woven clothes filter out the sun best.
- Practice protection from the sun even when it is cloudy. As much as 80 percent of the sun's rays can penetrate light clouds, mist, and fog.
- Be especially careful near reflective surfaces such as sand, concrete, water, or snow. These surfaces can reflect up to 85 percent of the sun's rays.
How to treat Skin Cancer
Melanoma tumors must be removed surgically, preferably before they spread beyond the skin into other organs. The surgeon removes the tumor fully, along with a safe margin of surrounding tissue. Neither radiation nor chemotherapy will cure advanced melanoma, but either treatment may slow the disease and relieve symptoms. Chemotherapy, sometimes in combination with immunotherapy is generally preferred. If melanoma spreads to the brain, radiation is used to slow the growth and control symptoms.
Immunotherapy is a relatively new field of cancer treatment that attempts to target and kill cancer cells by manipulating the body's immune system. Some of the most promising developments in the field of immunotherapy have sprung from efforts to cure advanced melanoma.