There are three different types of skin cancer that make up the majority of skin cancers. There are the nonmelanomatous types, which are squamous cell skin cancer and basal cell skin cancer, and then there is the more dangerous melanoma skin cancer. The first stages of skin cancer in all cases can be detected through changes in the appearance of the skin or an existing freckle or mole.
The most obvious first stages of skin cancer are any suspicious changes in the skin. Any change in a mole, for example it starts bleeding or itching, should be checked, as should the appearance of new moles or skin sores. Moles that have grown or whose edges have become less distinct are reasons to visit a dermatologist. Sores or ulcers that do not heal could also be skin cancer signs.
Basal cell carcinoma accounts for most skin cancer cases. It is the more slow moving of the three, and it rarely spreads via the bloodstream or lymph glands. The signs to look out for include an area of irritated skin, a pinkish or reddish scar or a raised, pearly nodule that will most commonly be found in parts of the body that are frequently exposed to the sun. Squamous cell skin cancer may appear as a skin ulcer or sore that is crusty or scaly and chronic in nature. This type of cancer can spread to other parts of the body, so early detection and removal is vital.
Once a nonmelanoma has been diagnosed, a skin biopsy will be carried out in order to determine the exact stage it is in; this is a process called staging. An examination of the lymph nodes may also be necessary so as to ascertain whether the cancer has spread to them. There are five stages of nonmelanoma, and the first stages of skin cancer are called stage 0, or carcinoma in situ, and stage 1. Carcinoma in situ is when abnormal cells are found in the outer layer of the skin called the epidermis. In stage 1, cancer has formed and the tumor is less than 1/8 inch (2 cm) at its widest point.
Melanoma is the most dangerous of the skin cancers that can spread to the lymph nodes and internal organs. There are a variety of signs indicating the first stages of skin cancer in this case, including pigmented lesions with an asymmetrical and/or blurred border. Any change in color, size, shape or texture could indicate a problem. A little less than half of melanomas form in preexisting moles, so any changes need to be examined immediately. The earlier a melanoma is detected, the more favorable the outcome.