Basal Cell Carcinoma
This is the most common form of skin cancer. Basal cells reside in the deepest layer of the epidermis, along with hair follicles and sweat ducts. When a person is overexposed to UVB radiation, it damages the body's natural repair system, which causes basal cell carcinomas to grow. These tend to be slow-growing tumors and rarely metastasize (spread). Basal cell carcinomas can present in a number of different ways:
- raised pink or pearly white bump with a pearly edge and small, visible blood vessels
- pigmented bumps that look like moles with a pearly edge
- a sore that continuously heals and re-opens
- flat scaly scar with a waxy appearance and blurred edges
Despite the different appearances of the cancer, they all tend to bleed with little or no cause. Eighty-five percent of basal cell carcinomas occur on the face and neck since these are areas that are most exposed to the sun.
Risk factors for basal cell carcinoma include having fair skin, sun exposure, age (most skin cancers occur after age 50), exposure to ultraviolet radiation (as in tanning beds) and therapeutic radiation given to treat an unrelated health issue.
Diagnosing basal cell carcinoma requires a biopsy — either excisional, where the entire tumor is removed along with some of the surrounding tissue, or incisional, where only a part of the tumor is removed (used primarily for large lesions).
Squamous Cell Carcinoma
Squamous cells are found in the upper layer (the surface) of the epidermis. They look like fish scales under a microscope and present as a crusted or scaly patch of skin with an inflamed, red base. They are often tender to the touch. It is estimated that 250,000 new cases of squamous cell carcinoma are diagnosed annually, and that 2,500 of them result in death.
Squamous cell carcinoma can develop anywhere, including inside the mouth and on the genitalia. It most frequently appears on the scalp, face, ears and back of hands. Squamous cell carcinoma tends to develop among fair-skinned, middle-aged and elderly people who have a history of sun exposure. In some cases, it evolves from actinic keratoses, dry scaly lesions that can be flesh-colored, reddish-brown or yellow black, and which appear on skin that is rough or leathery. Actinic keratoses spots are considered to be precancerous.
Like basal cell carcinoma, squamous cell carcinoma is diagnosed via a biopsy — either excisional, where the entire tumor is removed along with some of the surrounding tissue, or incisional, where only a part of the tumor is removed (used primarily for large lesions).
Treatments for basal cell carcinoma and squamous cell carcinoma include:
- Cryosurgery Some lesions respond to cryosurgery, where liquid nitrogen is used to freeze off the tumor.
- Curettage and Desiccation — This treatment involves using a small metal instrument (called a curette) to scrape out the tumor along with an application of an electric current into the tissue to kill off any remaining cancer cells.
- Mohs Micrographic Surgery — The preferred method for high-risk tumors or those in cosmetically sensitive areas, Mohs Micrographic Surgery combines removal of cancerous tissue with microscopic review while the surgery takes place. By mapping the diseased tissue layer by layer, less healthy skin is damaged when removing the tumor.
- Prescription Medicated Creams — These creams can be applied at home. They stimulate the body's natural immune system over the course of weeks.
- Radiation Therapy — Radiation therapy is used for difficult-to-treat tumors, either because of their location, severity or persistence.
- Surgical Excision — In this treatment the tumor is surgically removed and stitched up.
Roughly 90% of nonmelanoma cancers are attributable to ultraviolet radiation from the sun. That's why prevention involves:
- Staying out of the sun during peak hours (between 10 a.m. and 4 p.m.).
- Covering up the arms and legs with protective clothing.
- Wearing a wide-brimmed hat and sunglasses.
- Using sunscreens year round with a SPF of 15 or greater and sunblocks that work on both UVA and UVB rays. Look for products that use the term "broad spectrum."
- Checking your skin monthly and contacting your dermatologist if you notice any changes.
- Getting regular skin examinations. It is advised that adults over 40 get an annual exam with a dermatologist.