Precise Radiation for Skin Cancer
Although it is the most common type of cancer in the United States today, skin cancer can almost always be treated if detected and diagnosed early. Treatment usually requires surgery to remove the tumor. While not often used to treat the primary tumor, radiation therapy is often used to kill cancer cells remaining after surgery or to treat skin cancer that has spread to other areas. It can also be used to relieve symptoms of skin cancer that has spread to the brain or bone. However, older radiation methods can expose nearby, healthy tissue to damage.
Cutting-edge therapies such as Intensity Modulated Radiation Therapy (IMRT) and Image-Guided Radiation Therapy (IGRT) enable physicians to deliver higher and ultra precise doses of radiation to cancerous skin tumors while sparing nearby healthy tissue. This is particularly significant for skin cancer, which can appear anywhere on the surface of the body and place critical areas at risk.
What Is Skin Cancer?
Skin cancer occurs when there are abnormalities in the cells that make up the skin. Abnormal cells can form benign tumors (which are not cancerous), or malignant tumors (which are cancerous). There are two main types of malignant cancers, both of which have a nearly 100% cure rate when found early:
- Basal cell carcinoma is a slow-growing cancer found in the base of the epidermis that accounts for about 90% of all skin cancers. It seldom spreads, but if left untreated can invade bone and other tissues under the skin.
- Squamous cell carcinoma is found on the surface of the skin. It can be more aggressive, can grow deep below the skin and spread to distant areas of the body.
- Actinic keratosis (also called solar keratosis) is a pre-cancerous condition that can turn into squamous cell carcinoma.
A third type of skin cancer, called melanoma, begins in the cells that produce pigment in the skin. This type is less common, but more serious. However, if caught early, there is a nearly 97% chance for cure.
Who Gets Skin Cancer?
According to the American Cancer Society, more than one million cases of skin cancer are diagnosed each year, making it the most common type of cancer in the United States. It is estimated that 40 – 50% of Americans will have skin cancer at least once by the time they are 65. When caught early, people rarely die of skin cancer.
Melanoma, the most serious type of skin cancer, accounts for less than 5% of all cases, but causes the most deaths. Overall, the lifetime risk of getting melanoma is one in 50 for whites; 1 in 1,000 for blacks and 1 in 200 for Hispanics.
The biggest risk factor for any type of skin cancer is ultraviolet light, particularly sunlight, especially when it leads to sunburn. Other risk factors include:
- Age – as it relates to long-term exposure to the sun.
- Appearance – although any skin is at risk, people who have red or blond hair, fair skin, freckles or light colored eyes are at highest risk.
- Family history – particularly a family history of melanoma, increases risk.
- Recurrence – a person who develops skin cancer is at risk of developing the same cancer again, even in another place.
- Employment – working around coal tar, arsenic compounds, creosote, pitch and paraffin oil increase the risk.
- Skin injury or condition – skin that has been scarred or burned could be at higher risk as could skin that has actinic keratosis (also called solar or senile keratosis), which is a precancerous condition of thick, scaly patches.
The best prevention for skin cancer is to avoid prolonged exposure to ultraviolet light (sunlight), or to wear protective clothing and/or sunscreen.
How Do I Know If I Have Skin Cancer?
Most skin cancers can be seen on the surface of the skin, so it is important to perform self-checks and watch for unusual moles, lumps, sores, blemishes, markings, changes in the way skin looks or feels or spots that change in size, shape, sensation or color or don’t heal.
Basal cell carcinoma appears as a small, pink bump or patch. It is usually found on the head or neck, but may appear on any part of the body. Squamous cell carcinoma looks like basal cell carcinoma, but is usually more scaly and rough. It appears on the head, neck, ears, lips, backs of arms and hands and areas of the skin that have scars or ulcers.
When examining the skin, follow the ABCDEs for early skin cancer detection:
- Asymmetry of the two sides of the lesion.
- Border irregularity.
- Color variegation (non-uniform color).
- Diameter greater than 1/4″ (size of a pencil eraser).
- Elevation: is the lesion growing in height?.
The first step in diagnosing skin cancer is a medical exam, during which a physician examines the suspect spots. The physician may make a referral to a dermatologist for a more in-depth exam. As with other cancers, the only way to know for sure is with a biopsy—a procedure in which all or part of the tumor is sent to the lab to be examined under a microscope. The sample can be “shaved,” “punched” or cut from the skin.
Lymph nodes are olive-shaped glands that carry cancer from one area of the body to another. If it is suspected that the cancer has spread to the lymph nodes, these may be biopsied as well. If advanced melanoma is suspected, it may require a needle or surgical biopsy as well as chest x-rays, CT, MRI, PET, and/or bone scans to determine if it has spread to other areas of the body.
What Are My Treatment Options?
Although there are many types of therapies for skin cancer, basal cell cancers, squamous cell cancers and early stage melanoma can often be completely cured by minor surgery. Physicians use the size and location of the skin cancer, as well as the results of the diagnostic tests to determine the best course of treatment. Patients should work together with their physician to choose among several treatment options that may be used alone or in combination, and understand the risks and benefits of each.
Most surgical procedures for skin cancer are relatively minor. The skin is numbed and then the tumor is removed, along with some of the surrounding tissue, which is checked to make sure there are no remaining cancer cells. If melanoma is suspected, some lymph nodes may also be checked and removed. In rare cases of skin cancer on the fingers or toes, amputation may be necessary.
Cryosurgery is a procedure in which liquid nitrogen is applied directly to the skin to freeze and kill cancer cells. With Photodynamic therapy (PDT), drugs that collect in cancer cells and make them sensitive to light are placed on the skin or injected into the blood. A special light is used to activate the drug and kill the cancer cells.
Immunotherapy involves drugs or vaccines taken orally or applied to the skin that can help the immune system better attack the cancer. It is typically used as an added therapy after surgery for people with advanced melanoma.
Unlike chemotherapy used for other cancers, chemotherapy for skin cancer is a cream applied directly to the skin (topically). The chemotherapy drug in the cream reaches and kills cancer cells near the surface of the skin. It cannot reach deeper cancer cells or ones that have spread, so this therapy is primarily used for certain types of skin cancer or skin conditions that could become cancer.
Radiation therapy uses high energy rays to kill cancer cells. Although it may be used as a primary treatment for melanoma, it is not typically used to kill an original skin tumor. It is primarily used to treat skin cancer that has returned after surgery or cancer that has spread. It can also help shrink tumors to control symptoms. Side effects are usually limited to irritation around the radiation site, although many patients also report fatigue.
Electron Beam Radiation Therapy Electron beam radiation is a special type of radiotherapy that consists of very tiny electrically charged particles that can be treated on linear accelerator and directed toward the skin. The electron beam has characteristics that make it valuable for the treatment of skin cancer. This radiation is very damaging to the skin cancer cells but is fairly well tolerated by the surrounding normal skin cells. Also, the radiation penetrates only a very short distance into the skin so that internal organs can be completely spared from its effects.
Your Skin Cancer Treatment Partner
At Rainier Cancer Center, we offer patients a variety of treatment options, including electron beam radiation therapy with sophisticated treatment planning technology that may not be widely available in other treatment centers. We pride ourselves on providing each patient with the best outpatient experience in the most comfortable atmosphere. Our personal Cancer Navigators help each patient personally through their journey.
Electron Beam Radiation Therapy:
Fighting Skin Cancer with Precision
Used alone, electron beam radiation therapy is widely available for the treatment of skin cancer. However, at Rainier Cancer Center, we combine this therapy with powerful treatment planning software and deliver the radiation using the same linear accelerator we use to provide Intensity-Modulated Radiation Therapy (IMRT) and Image-Guided Radiation Therapy (IGRT) for internal cancers. This combination allows for more effective doses of radiation to be delivered to the affected area with less damage to the surrounding skin and tissue. Since skin cancer can appear anywhere on the body, but particularly in the head and neck area, this method of delivering the radiation therapy can help spare critical underlying organs, including the brain.
For patients, sophisticated electronic beam radiation therapy means:
- more effective treatment focused on skin cancer cells.
- less radiation exposure to surrounding skin and underlying organs.
- potentially fewer and milder side effects.
What to Expect During Treatment
First, we’ll schedule an appointment with a radiation oncologist. During this visit, we’ll perform a simulation of the treatment. You will be positioned on the treatment machine the same way you will be for actual treatment. The radiation oncologist will determine the need to use an immobilization device (such as a cast, mold or headrest) to keep you in the same position during treatment. The radiation oncologist will mark the area(s) to be treated, either on your skin or on the immobilization device. Simulation sessions take 30 to 60 minutes and may be repeated at intervals throughout your course of treatment.
Next, your radiation oncologist and treatment team will design a treatment plan tailored to you. They will use information from the simulation session, previous medical tests and, in many cases, sophisticated treatment planning software.
For skin cancer, the schedule for radiation therapy varies and will be determined by your radiation oncologist. During each session, positioning takes from 5 to 15 minutes. Actual treatment time lasts about 10 minutes and is painless. The radiation is delivered using a machine called a “linear accelerator” which generates x-rays or photon radiation. The linear accelerator moves so that patients can lie comfortably without being re-positioned during treatment.
The treatment room is spacious, and you will not be completely enclosed by equipment. A radiation therapist will position you to ensure successful treatment then go to an adjoining control room. From there, he or she will monitor you closely during radiation treatment using video cameras. The therapist can hear you at all times, and the treatment can be immediately discontinued if you feel uncomfortable or ill. Once each treatment is complete, you can return to your normal daily activities. A temporary sunburn effect may occur and can be treated with a typical cream or ointment as prescribed by your radiation oncologist.
A follow up exam with your radiation oncologist will be scheduled after your last treatment to discuss side effects. From there, your physician will determine the proper course of ongoing treatment.