The skin is composed of many different types of cells—basal cells, squamous cells, melanocytes, others—that naturally grow and slough off over time. A diagnosis of skin cancer means some of these cells have become abnormal (or mutated) and are starting to reproduce out of control.
What is skin cancer?
The skin is composed of many different types of cells—basal cells, squamous cells, melanocytes, others—that naturally grow and slough off over time. A diagnosis of skin cancer means some of these cells have become abnormal (or mutated) and are starting to reproduce out of control. This happens largely as a result of accumulated sun damage, although other factors, such as skin type, genetics, and environmental exposure, are also involved.
Basal cell carcinoma is the most prevalent form of skin cancer. It occurs in the skin’s top layer (called the epidermis). The cells gather into clusters and replicate, growing slowly and forming painless, translucent bumps. Most appear on the face, although any part of you exposed to the sun is vulnerable: ears, neck, back, chest, arms, legs. It’s rare, however, for these cancers to grow deep into the skin or spread to internal organs.
Squamous cell carcinoma also starts in the epidermis. Its earliest precancerous form is often actinic keratosis lesions, or sun spots. Squamous cell cancer may begin as raised, reddish lumps, which sometimes become open sores (ulcerate). It’s relatively unusual for this type of cancer to spread beyond the skin, but it can be deadly if it does. You’re at increased risk for a more involved type of squamous cell cancer if the lesion develops on the penis or the vulva as a sequel to an infection with certain strains of genital warts.
Far less common but more dangerous is malignant melanoma. This skin cancer arises from melanocytes—cells that produce melanin, the pigment that gives color to skin, hair, and eyes. Melanin is concentrated in most moles and also acts to protect your skin from the sun’s ultraviolet (UV) radiation, giving you a tan as a defense mechanism. Melanocytes that reproduce too quickly and appear as irregularly shaped, light-brown to black blemishes, signal trouble. This can occur within an existing mole, on unblemished skin, or, rarely, in the eye or under nails. Left unattended, a melanoma will penetrate deep into the skin and may spread (metastasize) via the lymphatic system or the bloodstream.
Treatment for skin cancer
The purpose of skin cancer treatment is to halt further growth of any malignancy. The specific approaches that your doctor will use are tied to your particular type of lesion. For most basal cell and squamous cell cancers that have not spread, the strategy is the same: Destroy the lesion by burning, freezing, or scraping it off. Usually not painful, these procedures are done in a doctor’s office after numbing the site with a local anesthetic.
For basal cell or squamous cell cancers that have spread, nonsurgical techniques (medication, radiation, or other therapies) are generally used. In choosing the appropriate treatment, you and your doctor will weigh factors such as where the lesion is, how deep it is, and how quickly it’s growing. Before treatment begins, make sure your skin cancer diagnosis has been confirmed with a biopsy, a laboratory analysis of the excised tissue.
A malignant melanoma that’s caught early, as a “local” cancer, is removed surgically. Your prospects for a full recovery are excellent; nearly 95% of superficial malignant melanomas can be cured. But once the cancer has penetrated deeper (even just a couple of millimeters down or into your lymph nodes), the strategy changes dramatically. Melanoma can spread quickly and prove fatal. While melanoma accounts for only 4% of skin cancer diagnoses, it’s responsible for 80% of skin cancer deaths. Cutting out the cancer is still crucial, but so are chemotherapy or radiation, which may slow down the tumour and ease discomfort. Once a melanoma has spread, “cures” are rare, so early detection and removal are key.
In very rare cases, a melanoma spontaneously disappears when the immune system mounts a strong resistance. Researchers, witnessing this fierce stand, are exploring the value of immunotherapy drugs, therapeutic vaccines, and other strategies to stimulate the immune system of patients with malignant melanoma. Early results of these novel therapies show promising results and safety in the treatment of malignant melanoma.
Medications for skin cancer
For basal cell carcinoma, prescription creams such as fluorouracil (Efudex, Fluoroplex) are used with caution because cancer can still spread under the healed surface of the skin. Many experts are now placing hope in a cream called imiquimod (Aldara), normally used for genital warts. In pilot studies, this cream has successfully cleared up superficial basal cell cancers in about 90% of patients.
Medications aren’t needed to treat thin melanomas (typically less than 1.5 mm thick), but if the skin cancer has spread, you’ll want to consider chemotherapy to stop the growth and ease discomfort. Just remember no drug is a “cure” and any can cause side effects. Some drugs are given intraveneously, others are taken orally. Dacarbazine (DTIC) is commonly used, although a combination of DTIC, carmustine (BCNU), cisplatin, and tamoxifen is becoming popular. Researchers worldwide are constantly testing new blends.
If your melanoma is advanced, you might want to find out about the developing field of immunotherapy (also called biological therapy). This drug strategy enlists the help of interferon-alpha (Intron-A), interleukin-2 (IL-2), and tumour necrosis factor (TNF). These chemicals occur naturally in your body and are produced in part by your white cells. When manufactured outside the body, these agents can be injected in drug form to stimulate your immune system to vigorously fight the melanoma tumour.
Clinical trials report long-term remission (sometimes for years) in about 6% of people taking Intron-A and IL-2, but many refinements are still needed. The agent most commonly used—interferon-alpha—boosts survival only modestly. It can be highly toxic (many liken side effects to a bout of flu).
Experimental work in combining immunotherapy with antimelanoma vaccines has generated great excitement. Unlike flu vaccines, such drugs are not given to prevent the disease, but to keep it from getting worse. The injection contains fragments of melanoma cells called antigens, which are little flags on the cell surface that signal they are foreign invaders. By bombarding the body with these antigens, it’s hoped the immune system will launch its own attack on the melanoma cells. While there’s no vaccine on the market just yet, clinical trial successes are generating high expectations for this treatment approach.
For a melanoma that has spread or reappeared on an arm or leg, ask about chemotherapeutic regional perfusion. In this technique, drugs are infused into affected areas, sparing most of the body a toxic reaction to chemotherapy.
Take care to avoid UV rays in any way possible. Two smart moves you can make are to check your own skin frequently for suspicious changes and schedule regular skin checks with a dermatologist.
The bottom line: The earlier you catch a skin cancer, the greater your chances of eliminating it with minimal scarring, and in the case of malignant melanoma, staying alive.
Related Procedures for Skin Cancer
The treatment method chosen for a particular cancerous lesion will depend on its biopsy and diagnosis.
For basal cell cancer. One of the most common approaches is surgical excision, which involves cutting out the abnormal growth and closing the area with stitches. Laboratory analysis can then determine whether the edges of the excised tissue (margins) are free of cancerous cells. Excision is slightly less likely to be linked to a recurrence than if the tissue is “destroyed.”
Depending on the type of skin cancer lesion and its location, your doctor may recommend curettage and electrodesiccation. In this technique, the cancer is scraped away with a sharp, ring-shaped instrument called a curette. An electric wand is used to cauterize the base of the growth. The procedure is only as effective as the operator’s skill, so try to find a doctor who has done it hundreds of times. Three cycles of treatment are typically needed. You’ll probably be left with a broad, pale scar.
For lesions on the head and neck, where scarring can be a real cosmetic issue, Mohs micrographic surgery may be your best option. It’s also valuable for skin cancers that are likely to (or have already) reappeared despite conventional treatments, for lesions with scar tissue that have nondefined edges, and for cancers that are growing fast or uncontrollably. Invented in the 1930s by Dr. Frederic E. Mohs, the procedure involves removing a tumour gradually, layer by layer. Each section is processed in the doctor’s office and examined on the spot under a microscope. Removal continues until a cancer-free layer of tissue is reached. Mohs offers the highest cure rates and the least tissue loss; an important consideration for skin cancers that have developed on the face (eyelids, lips, temples, nose, ears). Cure rates for basal cell cancers treated with Mohs are as high as 99%. Be sure to find a dermatologist specifically trained in this specialized type of surgery.
Another option for small basal cell cancers on the head and neck is cryosurgery. In this procedure, liquid nitrogen is applied to an abnormal growth to freeze and kill the malignant cells. The dead tissue falls off as the area thaws. You might feel slight pain and have swelling for a while, and more than one freezing may be needed. Eventually a white scar may form in the area that has been treated. With laser therapy, a narrow, concentrated beam of light is used to remove or destroy cancer cells. This technique is used only for very superficial skin cancers.
For advanced basal cell cancer. If a basal cell cancer has grown significantly and is proving very difficult to treat, your doctor might recommend x-ray radiation. Some doctors recommend radiation following surgery to ensure that every last cancer cell is destroyed. Radiation is used slightly more often for squamous cell cancers than for basal cell growths because the former carry a greater risk of serious illness at all stages.
For squamous cell cancer. The preferred treatment approach is simple excision with a scalpel, though some small, superficial lesions can be successfully treated with curettage and electrodesiccation. Another option is cryotherapy. Lesions on the lips, ears, nose, or other sensitive facial areas, as well as aggressive tumours and lesions that have reappeared, are best treated with Mohs surgery. Although not yet widely available, a specialized technique called photodynamic therapy is often a good choice for treating multiple superficial basal cell cancers or a squamous cell cancer. The technique involves applying or ingesting a chemical that makes skin cells sensitive to a precise colour of laser light. When applied, the laser instantly destroys only the cancerous cells.
For malignant melanoma. You’ll need to have a surgical excision of the growth itself, along with (typically) at least a half inch of normal surrounding skin cut out as a safety precaution. This is done to thwart the growth of any lingering cancerous cells. If you have had a relatively superficial melanoma removed, the wound will take one to two weeks to heal. Avoid heavy exercise during this period so the incision can heal properly.
If there’s any chance that malignant melanoma has traveled to your lymph nodes, the surgeon will remove the nodes for examination. Taking out the nodes may help prevent the cancer from spreading throughout your lymphatic system. If the cancer has already spread, surgically removing the nodes may ease pain and increase your chance of survival. Radiation may help relieve discomfort with metastatic melanoma, but won’t destroy it.
Questions for Your Doctor
- What number sunblock is the best for my skin type?
- Given my history, how often should I schedule a checkup with a dermatologist?
- What are the chances that my melanoma has been misdiagnosed?
Living with Skin Cancer
If you're living with skin cancer, here are a few quick tips to help you take control:
- Push for an appointment. If there‘s something suspicious on your skin, be proactive about getting it checked, and if necessary, removed. See a skin doctor (dermatologist) specializing in skin cancer if you can.
- Give up the tanning parlor and sun lamp. Neither is safe. A recent study found that people who used any type of tanning device have a 2.5 times greater risk for squamous cell cancer and a 1.5 times greater risk for basal cell cancer.
- Reach out. A diagnosis of skin cancer, especially a malignant melanoma, can be frightening. Talk with your doctor. Look to friends, family, and support groups. De-stress with exercise and yoga.
- Question Internet info. A study from the University of Michigan found many popular melanoma websites are simply wrong about diagnosis and treatment options.
- Sign up for a clinical trial if your melanoma is advanced. It’s a chance to benefit from new treatments.
- Catch the next one early. Every month, use a mirror to examine every inch of your skin. Have someone check hard-to-see places. Call the doctor about alterations in lesion shape, colour, or size. A cancer study found that 57% of nearly 500 melanoma patients detected the cancer on their own.
- Tell family members to get screened regularly, especially if you‘ve had a melanoma. Your skin cancer means they‘re at increased risk as well.
Adapted from Knowing Your Options: The Definitive Guide to Choosing The Medical Treatments, Reader's