Each year in the U.S. over 5.4 million cases of non melanoma skin cancer are treated. Skin cancer is the most common of all human cancers. Cancer occurs when normal cells transform, grow and multiply without normal controls. They form a tumor. Tumors are cancerous only if they are malignant. They encroach on and invade neighboring tissues.Tumors travel to remote organs via the bloodstream. Tumors overwhelm surrounding tissues by invading their space and taking the oxygen and nutrients they need to survive and function.
There are three major types of skin cancers: basal cell carcinoma, squamous cell carcinoma, and melanoma.
The vast majority of skin cancers are basal cell carcinomas and squamous cells carcinomas. These are unlikely to spread to other parts of the body.
A small number of skin cancers are malignant melanomas. Malignant melanoma is a highly aggressive cancer that tends to spread to other parts of the body. These cancers may be fatal if not treated early.
Skin cancers start as precancerous lesions. These precancerous lesions are changes in skin that are not cancer, but could become cancer. These changes are also known as dysplasia. Some specific dysplastic changes that occur in skin are:
Actinic keratosis is an area of red or brown, scaly, rough skin, which can develop into squamous cell carcinoma.
A nevus is a mole, and abnormal moles are called dysplastic nevi. These can potentially develop into melanoma.
Moles are simply growths on the skin that rarely develop into cancer. Dysplastic nevi, or abnormal moles, are not cancer, but they can become cancer. People sometimes have as many as 100 or more dysplastic nevi, which are usually irregular in shape, with notched or fading borders. Some may be flat or raised, and the surface may be smooth or rough.
Skin cancer symptoms
Non-melanoma skin cancer symptoms
An unusual skin growth, bump or sore that doesn’t go away may be the first indication.
Basal cell carcinomas on the head or neck may first appear as a pale patch of skin or a waxy translucent bump. It may be possible to see blood vessels in the center of the bump or there may be an indentation in the center. If the carcinoma develops on the chest it may look more like a brownish scar or flesh-colored lesion. As the cancer develops, it may bleed if injured or ooze and become crusty in some areas.
Squamous cell carcinomas may also develop as a lump on the skin. However, these firm lumps may be rough on the surface, unlike the smooth and pearly appearance of a basal cell carcinoma. If a nodule doesn’t form, the cancer may develop more like a reddish scaly patch. Whereas a skin rash may go away with time, these rough lesion-like patches remain and continue to develop slowly. This type of cancer typically is found on the head, neck, hands or arms, but they can also develop in other areas, such as the genital region or in scars or skin sores.
However, both basal cell and squamous cell carcinomas may also develop as a flat area that does not look much different from normal skin, so it is important be aware of the symptoms of skin cancer.
Melanoma skin cancer signs include new spots on the skin, or a change in size, shape or color of an existing mole. How to recognize abnormal growths:
- Asymmetry: A mole that has an irregular shape, or two different looking halves.
- Border: Irregular, blurred, rough or notched edges may be signs of skin cancer.
- Color: Most moles are an even color – brown, black, tan or even pink – but changes in the shade or distribution of color throughout the mole can signal melanoma.
- Diameter: Moles larger than ¼ inch (6 mm, the size of a pencil eraser) across may be suspect, although some melanomas may be smaller than this.
Other potential signs of melanoma in a mole include:
A sore that does not heal
Pigment, redness or swelling that spreads outside the border of a spot to the surrounding skin
Itchiness, tenderness or pain
Changes in texture or scales, oozing or bleeding from an existing mole
Checking for skin cancer symptoms
Examination of the skin for any new or unusual growths, changes in the size, shape or color of an existing spot, is key to finding and treating skin cancers early.