1. WHAT CAUSES SKIN CANCER?
The association of sun exposure with skin cancer is well established. People with lighter skin (especially those who don't tan) are more susceptible to skin cancer. Skin wrinkling and skin cancer relate to total sun exposure over one's entire life.
2. WON'T I HAVE EARLY WARNING SIGNS?
Even patients who never sunbathe receive thousands of hours of lifetime exposure. Unfortunately, when the total dosage reaches a critical point, patients start noticing precancerous and cancerous lesions. These may appear in large numbers and at frequent intervals. A patient may have had smooth skin until age 30, 40, or 50 and suddenly begins to develop precancerous or cancerous lesions several times a year. They cannot undo the sun damage now. They can decrease further radiation damage by wearing sunscreen lotions regularly. This will not, however, keep radiation damage at zero. Patients will even develop lesions in winter. X-ray treatment in the past also predisposes to skin cancer. We should know of any such previous treatment.
3. WHAT IS THE MOST COMMON TYPE OF SKIN CANCER?
Basal cell carcinoma is the most common cancer in the United States. Approximately 500,000 new cases occur each year. We treat this kind of skin cancer many times daily in our office.
It usually appears as a pimple-like spot that does not seem to go away. Almost all patients thought it was a pimple at first. They tend to pick at it, believing this is the reason the lesion persists. Any pimple should be gone within 1-2 months. If a pimple is still on the face after a 2 month period, make sure we check it.
This cancer does not usually metastasize (one study reported one in 3000 spread to other organs) and, therefore, it is rarely fatal, except in persons who neglect it. It does grow locally in the area in which it develops with the potential of destroying adjacent structures (for example nose, cheek, eyelid, etc.) and must, therefore, be treated to prevent this.
4. HOW IS BASAL CELL CARCINOMA TREATED?
I use surgical excision with suturing, laser excision, or curettage and electrodesiccation (using a sharp surgical curette to remove the tumor and for biopsy while making sure the entire tumor is gone, and subsequent burning with an electric needle). I find cure rates with any of these methods to be well over 95%.
The surgical procedures described above should be completely painless, with the patient feeling only the slightest prick with a local anesthetic.
Another method reserved for the most difficult skin cancers, in my opinion, is called Moh's chemosurgery. This method may leave larger defects that can take a significant period of time to heal. It is, therefore, not usually my initial therapeutic choice. This method involves taking small pieces of skin and checking them to ensure complete removal of a large tumor or difficult recurrent tumors.
We may occasionally use cryosurgery (freezing) or x-ray to treat some skin cancers.
In some carcinomas, large size or difficult location may lead me to suggest that our plastic surgeon excise the cancer. This would be recommended if indicated; however, most lesions can be treated quite simply in the office.
5. WHAT IS APPROPRIATE FOLLOW-UP CARE FOR EARLY DETECTION AND TREATMENT?
Patients who have had a skin cancer will be prone for life to develop others, just as a patient with cavities will be so predisposed. Studies have shown a 35-50% incidence of an additional skin cancer (basal and squa-mous cell types) within 3 years after treatment of the first cancer.
A small percentage of cases may recur but are usually detected at an early stage when patients are followed routinely. Every 3 months (for 1 year) after removal of any cancer and every 6 months lifelong are current recommendations. Patients who follow this routine rarely have significant problems because lesions are found when they are small.
Some areas, such as the forehead and nose, may develop several skin cancers. Former President Reagan developed one skin cancer on his nose and had another one develop on the nose shortly thereafter, and a recurrence, according to reports. This is another reason for frequent lifetime check-ups by any patient having basal cell carcinoma.
6. WHAT SHOULD I LOOK FOR?
The face, neck, tops of the hands and arms are most frequently exposed to ultraviolet light from the sun. 90% of all skin cancers (except melanoma) occur in these areas. These are the areas that patients should watch most carefully, although all skin should be checked monthly at home. The following signs of skin cancer (basal and squamous cell) should be closely looked for:
1. An open sore or pimple that bleeds, oozes or crusts and remains for one month or more. A persistent nonhealing pimple should be checked. Almost all patients (including former President Reagan) call skin cancer a pimple that they usually pick at. They invariably think this is the reason it is still present.
2. A reddish patch or irritated area, especially on sun exposed skin. It may or may not be symptomatic. Most skin cancers do not cause the patient any discomfort. Many skin cancers will also never bleed.
3. A shiny bump that can be a pearly color or pinkish-red color.
7. WHAT ARE PRE-CANCERS AND SQUAMOUS CELL CARCINOMA?
Actinic keratoses (pre-cancers) usually present as small reddish patches that may have a slight brownish tinge. They may be slightly scaly and occasionally bleed. One usually notices it as a small patch that will scale or is rough and looks slightly different than the surrounding skin. One key in differentiating this from a benign area is that these areas will still be there one or two months later. Any persistently different area of skin should be checked by a dermatologist.
These keratoses will lead to a somewhat more difficult skin cancer, squamous cell carcinoma, if not treated. They usually grow slowly and may take several years before turning into a squamous cell carcinoma; however, patients should not delay in treatment, as some may develop into squamous cell carcinoma rather rapidly. Although squamous cell carcinoma of the sun-exposed skin does not frequently spread to other organs (metastasize), this is possible (approximately 5-10% reported in different studies) and, therefore, should be treated early. As these develop into squamous cell carcinoma, the scale may become thicker and the lesion may grow deeper.
These premalignant keratoses can be easily treated with superficial therapy, such as freezing with liquid nitrogen. This causes a scab or blister and heals usually within 1 or 2 weeks. This method removes the diseased top layer of the skin. Presidents Clinton and Bush have had several actinic keratoses treated with this method. A topical chemical, 5-fluorouracil, may be used, but may cause too much irritation of the skin for some patients. It is used mostly for patients with large numbers of actinic keratoses.
Although actinic keratoses are precursors of squa-mous cell carcinoma and therefore can be detected in a premalignant phase, basal cell carcinoma does not have any precursor lesion. Basal cell carcinoma develops from the very beginning as a basal cell carcinoma.