Types of Skin Cancer
There are several types of skin cancer, the most common being Basal Cell carcinoma. Basal Cell carcinoma most often occurs on the sun-exposed areas of the skin and may look like an open sore, reddish patch, or waxy growth with an elevated border and central indentation. Treatment of Basal Cell cancer includes: excisional surgery, electrosurgery, microscopically controlled surgery and radiation.
The second most common type of skin cancer is Squamous Cell carcinoma. Squamous cell carcinoma also occurs most often on sun-exposed skin and may look like a scaly red patch with irregular borders, a wart-like growth, or an open sore. These cancers may bleed easily if bumped or disturbed. Treatments for this type of cancer include: excisional surgery, electrosurgery, radiation and microscopically controlled surgery.
The most dangerous type of skin cancer is Melanoma. Melanoma may occur on any area of the body and may resemble a mole, but there are important differences. If you notice changes in a mole you should contact a physician immediately. A melanoma may present as an asymmetrical lesion with an irregular border. If the color or pigmentation of the area is not uniform, or if the diameter of the area is greater than six millimeters, these are also danger signs.
Types of Lesions
In addition to these three types of skin cancer, there are two types of lesions that have the potential to progress into skin cancer. One type of pre-cancer is Actinic Keratosis, which appears as a scaly or crusty bump and can be treated with curettage and electrodissection, shave removal, dermabrasion, chemical peels, laser surgery, or topical medication. The second type is Dysplastic Nevi. Dysplastic Nevi are abnormal moles that resemble Melanoma and are often asymmetrical in shape, have an irregular border, vary in color, and are larger than normal moles. They should be watched carefully for changes that may indicate progressions to Melanoma.
It is important to remember that avoiding sun exposure and tanning beds and wearing sunscreen with an SPF of 30 or higher can best prevent these types of skin cancer.
Skin Cancer Treatment
There are five standard methods for the treatment of skin cancers. The two nonsurgical treatments are cryotherapy (deep freezing) and radiation therapy. The three surgical methods include simple excision, physical destruction (curettage with electrodesiccation) and Mohs micrographic surgery. Newer methods under investigation include photodynamic therapy and immunochemotherapy.
The treatment of each skin cancer must be individualized, taking into consideration such factors as patient’s age, location of the cancer, type of cancer and whether or not the cancer has been treated previously. In some instances, more than one type of therapy may be appropriate. But in most cases, only one or two are necessary for a particular skin cancer.
After the removal of the visible portion of the tumor by excision or curettage (debulking), there are two basic steps to each Mohs Micrographic Surgery stage. First, a thin layer of tissue is surgically excised from the base of the site. This layer is generally only 1-2 mm larger than the clinical tumor. Next, this tissue is processed in a unique manner and examined underneath the microscope.
On the microscopic slides, the entire bottom surface and outside edges of the tissue is examined. This tissue has been marked to orient top to bottom and left to right. If any tumor is seen during the microscopic examination, its location is established, and a thin layer of additional tissue is excised from the involved area. The microscopic examination is then repeated. The entire process is repeated until no tumor is found.
Mohs Micrographic Surgery allows for the selective removal of the skin cancer with the preservation of as much of the surrounding normal tissue as is possible. Because of this complete systematic microscopic search for the “roots” of the skin cancer. Mohs Micrographic Surgery offers the highest chance for complete removal of the cancer while sparing the normal tissue. The cure rate for new skin cancers exceeds 97%.
As a result, Mohs surgery is very useful and may be recommended for the following types of cancer:
- When the size or extent of the skin cancer cannot be defined easily.
- When the cancer is in a place, such as the nose, eyelids, lips or ears, where it is desirable to spare as much of the normal skin as possible.
- When the cancer returns after being treated.
- When the cancer is large.