Skin Cancer – Beyond the Basics
Most people have heard about melanoma, which arises from the normal pigment cells of the skin and can be potentially life-threatening if not removed early. However, as serious as these cancers are, there are two other forms of skin cancer which are much more common and frequently less understood. Each year about 75, 000 Americans will be diagnosed with melanoma (and about 9,000 will die) so we need to take this type of skin cancer most seriously. Yet over 3.5 million people in the US will be diagnosed with the more common types of skin cancer : basal cell and squamous cell. Another way of looking at the relative frequency of these cancers is that 2% of men and women will be diagnosed in their lifetime with melanoma, while 50% of those who live to age 65 will have either a basal or a squamous cell cancer diagnosed.
So what are the important things to know about these types of skin cancer? First, unlike melanoma, they are very unlikely to invade the deeper tissues of the body or metastasize to distant organs, though this can happen with the squamous variety. Instead they will become increasingly larger over time, causing disfigurement and pain. Second, just as with melanoma, your chances of acquiring this type of cancer goes up according to your skin type risk. Dermatologists have divided us up into six skin types, based on the amount of pigment we inherited, using a guide called the Fitzpatrick scale which goes from type I (the palest usually with northern European ancestry with red or light blonde hair, and never able to tan) to type VI (darkest, usually with African or Australian aboriginal ancestry and almost never gets sun-burned). But most importantly, the biggest risk that we can control is exposure to ultraviolet light, either natural sun or tanning rays. Regular use of sunblock at SPF 15 (SPF 30 if you are type I or II) should decrease you risk by 40-50% of being diagnosed will all three types of cancers.
There are some unique facts about non-melanomas that have may be lesser known. For example, the human papilloma virus (HPV) which can cause cervical cancer can also be associated with squamous cell cancer of the genital skin in men and women. Also, toxic chemicals including arsenic which is frequently found as a naturally occurring mineral in ground water in Maine, can greatly increase the chances of developing skin cancer. And of course smoking, which does not play a role in melanomas, has been shown to increase the development of squamous cell cancer of the lip and mouth.
One of the more challenging aspects of these cancers for the layman is that they do not have the same brownish/black appearance as melanomas. Instead, basal cell cancers which are the most common often have a reddish color, and act like a sore that does not completely heal. Frequently they will have a burning or itching sensation and occur most commonly on the head or upper torso. Squamous cell cancers usually have a grayish color associated with extra flaking or crusting, and are frequently found in folks who have a common precursor type called actinic keratosis, which is a slightly rough patch on sun-exposed surfaces of the skin.
Fortunately, early treatment almost always is curative. The most common treatment choice is often simple surgical excision that can sometimes be done without stitching depending on the size and location of the cancer. Cryotherapy, which is freezing with contact to the intense cold of liquid nitrogen, may be done if the cancer is still confined to the shallow layers of the skin. Additionally there are anticancer creams and gels that can be applied to the skin for 3-8 weeks and are effective, particularly if there a lot of precancerous changes over a wide area such as the face or scalp. For lesions on the face, an advanced technique called Moh’s surgery may be the best choice to minimize potential scarring.
So the bottom line on skin cancer remains:
1) Avoid sun especially the high risk times between 10 AM and 4PM, as well as tanning exposures to UV light
2) Apply sunblock with an SPF of 15 (or better yet 30 if you have light skin) at least 30 minutes before going out into the sun
3) Wear hats (especially if you are balding!) or other clothes to cover exposed skin when out as much as possible
4) See your health care provider if you have a spot that is new, sore, changing, enlarging or otherwise bothering you – your instincts may just be the best line of defense!