Skin cancer is the most common form of cancer in the United States. The skin is divided into three layers: the epidermis, the dermis and the subcutaneous layer. The epidermis is the outermost layer comprised of epithelial cells and contains no blood vessels. The dermis innervates the epidermis. The dermis rests on the subcutaneous layer which is the fatty layer attaching the skin to the underneath muscles and feeds and drains the capillaries of the dermis.
The top layer, the epidermis, is simple squamous epithelium made up of basal cells. Basal cells are a type of cells that produce new skin cells when the old skin cells die. Your cells are constantly undergoing division which is regulated by genes in your DNA which communicate with each other and tell the cells when to divide and when to stop. If the DNA sending the message is damaged or mutated the gene may not function properly. If you change the structure you change the function. It can occur that the DNA damage of the cell which controls the cell decision tells the cells to divide uncontrollably forming a tumor. Not all tumors are cancerous. Non- cancerous tumors are generally localized and not invasive to the surrounding tissue while cancerous tumors may metastasize and invade surrounding tissue. DNA damage due to UV radiation from the sun is the most common damage leading to skin cancer.
Basal cell carcinoma (BCC) begins in the basal cell layer of the epidermis. Basal cell carcinoma is the most common form of skin cancer involving approximately two million people a year. BCC is most commonly associated with excessive exposure to the sun mainly including the scalp, arms, shoulders, ears and back. BCC can occur on unexposed body parts commonly through radiation, complications of scars,burns, vaccines and even tattoos.
Basal cell carcinoma tumors are usually localized and do not affect surrounding tissue however early detection is important. Basal cell carcinoma can appear in different forms including waxy shiny bumps, wounds that wont heal, red irritated scars, oozing crusting elevated sores, sores that will not heal or easily bleeding sore skin. People that are higher risks include people with light colored skin, blue or green eyes, persons with red or blonde hair, many moles, excessive severe sunburns, long term daily exposure and over exposure to x-rays or other forms of radiation including tanning beds.
Basal cell carcinoma is diagnosed by a shave biopsy where the doctor removes a small scraping of the skin and it is then tested for cancer cells. Treatment of basal cell carcinoma varies depending on the size, shape, depth of the tumor, the patients age, general health and medical history. Procedures would include removal of the tumor and using stitches to place the skin back together, freezing or electricity to kill cancer cells, radiation if the tumor can not be surgically removed or skin cream medications.
How can basal cell carcinoma be prevented? Application of sun screen; minimum of 15 SPF range, including blockage from UVA and UVB lights, application every 30 minutes and usage in the winter as well. (Avoid tanning beds.) Examine your skin frequently for growths or changes in the color, size, shape and texture.
Possible complications would include the growth to surrounding areas, tissues and bone. Basal cell carcinoma rarely spreads but may if left untreated. The most worrisome areas include nose, eyes and ears. If you experience any changes or concerns contact you physician.
Sources:
http://www.medicinenet.com/skin_cancer/article.htm
The Human Body in Health and Disease – Memmler’s 11th Edition
http://www.nlm.nih.gov/medlineplus/ency/article/000824.htm
http://www.webmd.com/melanoma-skin-cancer/basal-cell-carcinoma
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001827/
http://www.mayoclinic.com/health/basal-cell-carcinoma/DS00925
