Prepared by Jill
Shelley and 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.
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.
Proportionally,
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.
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
NASD Review: 04/2002
This document is
extracted from
MF-1085
'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.
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