Jill Shelley, Michael Dennis
Kansas State University Research and Extension
Farming may be healthier than other occupations in many respects, but not when it comes to skin cancer. Most skin cancers are related to exposure to the ultraviolet radiation in sunlight. However, a sunburn can occur on an overcast day just as easily as a sunny day. The damage from ultraviolet rays accumulates over time.
"The people I'm seeing are usually in their 40s, 50s, 60s, 70s, or 80s. Some of them have numerous skin cancers and precancerous lesions. I've seen as many as 10 on one patient," said Dr. Robert Cathey, a dermatologist in Manhattan.
Among his patients is Ross Turner, who has farmed full-time or part-time all his life. When Turner reached 54 he had to have treatment each year for eight years for precancerous lesions on his head. "I grew up in the sun, I've been in the sun all my life. The heat thaws me out. I knew sunburn was painful but I never even thought about other effects. I've been bald since I was 23. I suppose I was one of those guys who thought I'm tough. The sun is not going to bother me."
Turner finally went to Dr. Cathey for treatment because he noticed some scaly places on his head and the backs of his ears that he would pick at. He read they could be precancerous.
The head and neck are the main areas for skin cancers, then the hands and forearms. On women, the upper chest and the lower leg are frequent sites. Malignant melanoma is the most dangerous form of skin cancer. On men this type of cancer is normally found on the upper back.
Fair skin is a risk factor, although by no means is skin cancer limited to people with fair skin. The greater the tendency to freckle, the greater the risk, generally speaking. And while most of us have moles, few new ones appear in adulthood. New "spots" on the skin in adults are warning signs. Very few cancerous spots will exhibit symptoms such as bleeding or pain.
"It can be hard to tell whether a spot is cancerous, and that's why we do a lot of biopsies, removing the spot and having it checked by a pathologist. It's a very simple procedure it takes just a few minutes with anesthesia, like getting a tooth filled. The report usually comes back from the pathologist in two or three days unless multiple pathologist need to look at it to confirm the results. In some places where the tissue must be sent to another town, it may be a week before we get the results," Dr. Cathey says.
Treatment varies. One of the determining factors in how to treat a skin cancer is how thick it is. The longer it is left untreated and the deeper it is, the more aggressive the treatment must be. Most skin cancers don't migrate to other parts of the body. Precancers such as Turner's can be "treated very easily, with no scarring, no needles, and not a great deal of discomfort, and it can save us from having to whittle on a patient down the road," Dr Cathey said.
Turner's precancers are treated with liquid nitrogen. "It looks terrible for awhile but they're decreasing. Dr Cathey has me convinced that if I continue treating them and wear a hat and sun blocker, I'll never have a serious problem."
Dr. Cathey says many farmers and ranchers don't want to see their family doctor or a specialist for a spot on their skin. "It's the persistent spouse that makes them go. Some lesions are no reason for concern, but they couldn't be expected to know that. Most of the time patients have reasonable concerns."
The American Cancer Society estimates as many as 6,000 new cases of skin malignancies will be diagnosed each year. Most are the result of excessive exposure to UV radiation. Kansas State University Extension Clothing Textiles Specialist Deanna Munson, says you can protect yourself from the sun by wearing the proper clothing. "Methods of protecting yourself include wearing hats that protect temples, tips of ears and the back of your neck and wearing long sleeves, long pants, gloves and high socks or boots."
Suggestions for protecting yourself from the sun include:
- Reduce duration of direct exposure
- Utilize sunscreen products
- Wear clothing made from fabrics designed to block UV radiation.
TYPES OF SKIN CANCER
Almost all skin cancers can be cured in their early stages with appropriate treatment. The treatment varies depending on the type of cancer and its thickness. A thicker cancer is more difficult to treat; prompt medical attention makes a difference. Ninety percent of all skin cancers are on parts of the body not usually covered by clothing.
The most common precancers are actinic keratoses, which are also called solar keratoses. They appear most frequently on skin that has been severely sun damaged as small crusty or scaly bumps with a skin-colored or pink base. Sometimes they are brown or red scaly patches. Because of their rough texture they are frequently found first by touch rather than sight. Sometimes they cause a pricking sensation. Their presence indicates that a person is at high risk for developing some type of skin cancer. Experts estimate that approximately 10-percent of these patches will evolve into squamous cell carcinoma if left untreated.
Of the approximately 600,000 new cases of skin cancers that will be diagnosed this year, about three-quarters of them will be basal cell carcinoma. Basal cell carcinoma usually appears as a small, fleshy bump or nodule, usually on sun exposed areas such as the face, head, ears, neck or arms. Basal cell carcinoma grows more slowly and does not metastasize (spread to other parts of the body) but it can cause deep damage.
Squamous cell carcinoma lesions also usually begin on the upper sun-exposed parts of the body. They may appear as nodules or as red, scaly patches; they can be recognized by their rough, irregular, scaly surface and indistinct borders. A lesion will increase in size over time and it can metastasize. About 20-percent of all newly-diagnosed skin cancers will be squamous cell carcinoma. Squamous cell carcinoma lesions on the lips, usually on the lower lip, are more likely to spread than are similar lesions on other parts of the body.
Even though only 5-percent of skin cancers are malignant melanomas, malignant melanoma is the eighth most common cancer in the United States today. Scientists estimated that 6,700 Americans would die of malignant melanoma in 1992. Its rate is increasing most rapidly in people 40 and younger.
Most malignant melanoma appears in mixed shades of tan, brown, black, and other dark colors, sometimes near a mole. Men are more likely to develop it on the upper back; the most common site on women is on lower legs.
more men than women die from malignant melanoma. Scientists
have several theories of why this is true. One most commonly
put forth is that the disease is more advanced before men
seek treatment. This may be because a man is more likely to
have a malignant melanoma where he can't see it.
This document is
'Health Concerns in Agriculture': A tabloid published by Extension
Agricultural Engineering, Kansas State University, Manhattan,
Kansas. Publication date: October 1993.
Prepared by Jill Shelley and Michael Dennis, Educational Materials Specialist, Cooperative Extension, Kansas State University, Manhattan, Kansas.
Publication #: MF-1085
Disclaimer and Reproduction Information: Information in NASD does not represent NIOSH policy. Information included in NASD appears by permission of the author and/or copyright holder. More
Reviewed for NASD: 04/2002