Types of Skin Cancer
Skin cancer is the most common form of human cancer, affecting more than one million Americans every year. One in five Americans will develop skin cancer at some point in their lives. Skin cancers are generally curable if caught early, which is why regular self-examination is so important.
The two most common types of skin cancer, basal cell carcinoma and squamous cell carcinoma, are discussed below. For more information on the third, and most dangerous, form of skin cancer, malignant melanoma, please click the Melanoma button on our Home page.
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 red shiny bump
- a sore that continuously heals and re-opens
- flat scaly red patch that looks like a small area of rash but never fades
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).
Treatments for basal cell carcinoma include:
- Curettage and Electrodesiccation — The preferred method of dermatologists, 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.
- Surgical Excision — In this treatment the tumor is surgically excised and sutured.
- Prescription Medicated Creams — These creams can be applied at home. They stimulate the body's natural immune system over the course of several weeks.
- Mohs Micrographic Surgery — The preferred method for large tumors, 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.
- Radiation Therapy — Radiation therapy is used for difficult-to-treat tumors, either because of their location, severity or persistence.
Squamous Cell Carcinoma
Squamous cell carcinomas commonly present as rough, gritty or scaly growths with inflamed red skin surrounding them. They are often tender to the touch. They tend to grow much faster than basal cell carcinomeas and rarely can metastasize, or spread to lymph nodes or internal organs. 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 most frequently appears on the face, ears, neck and backs of the hands. Squamous cell carcinoma tends to develop among fair-skinned, middle-aged and elderly people who have a history of sun exposure and repeated sunburn. Some squamous cell carcinomas evolve from actinic keratoses, rough, scaly "sandpapery" lesions that appear on sun-damaged skin. Actinic keratoses are therefore considered to be precancerous, so are removed, most commonly by cryotherapy (freezing with liquid notrogen) when found.
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 squamous cell carcinoma include:
- Curettage and Electrodesiccation — The preferred method of dermatologists, 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.
- Surgical Excision — In this treatment the tumor is surgically excised and sutured.
- Mohs Micrographic Surgery — The preferred method for large tumors, 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 several weeks.
- Radiation Therapy — Radiation therapy is used for difficult-to-treat tumors, either because of their location, severity or persistence.
What to Look For With Skin Cancer
The key to detecting skin cancers is to notice changes in your skin. Look for:
- Pigmented spots that are new or changing (darkening, growing or developing red or black areas).
- Translucent pearly pink or red dome-shaped growths.
- Existing moles that begin to grow, itch or bleed.
- Brown or black streaks under the nails.
- A sore that repeatedly heals and re-opens
- Rough scaly red patches.
The American Academy of Dermatology has developed the following ABCDE guide for assessing whether or not a mole or other lesion may be becoming cancerous.
A symmetry : Half the mole does not match the other half in size, shape or color.
B order : The edges of moles are irregular, scalloped, or poorly defined.
C olor : The mole is not the same color throughout.
D iameter : The mole is usually greater than 6 millimeters when diagnosed, but may also be smaller.
E volving : A mole or skin lesion that is different from the rest, or changes in size, shape, or color.
If any of these conditions occur, please make an appointment to see one of our dermatologists right away. The doctor may do a biopsy of the growth to determine if it is cancerous.
Skin Cancer Prevention
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.
For more information on Skin Cancers in the Austin, TX area call Central Austin Dermatology at (512) 450-1001 today!