Skin CancerSkin Cancer

Skin Cancer

What is Cancer? Changes to the DNA of a cell

(mutations) lead to cellular damage Mutations enable cancer cells to

divide continuously, without the need for normal signals

In some cancers the unchecked growth results in a mass, called a tumor

Cancerous cells may invade other parts of the body interfering with normal body functions

What is Cancer? Although cancer is often referred to

as if it were a single disease, it is really a diverse group of diseases that affects many different organs and cell types

The likelihood of developing any particular cancer depends on an individual’s genetics, environment, and lifestyle.

The occurrence of some cancers may be prevented/reduced by wise lifestyle choices.

Introduction to Skin

The skin is the body’s largest organ Roles of the skin:

• Prevents water loss (dehydration) • Shields the internal organs in the event of injury• Regulates body temperature• Senses outside stimulus such as touch as well as heat

and cold• Serves as a barrier to infection (14)

Introduction to Skin

Skin Cancer Basics

• An abnormal change in the skin resulting from uncontrolled cellular growth

• There are three main types of skin cancer:»Basal Cell Carcinoma (BCC)»Squamous Cell Carcinoma (SCC)»Melanoma

The Big Risk: Ultraviolet (UV) Radiation

Understanding UV Radiation • The nuclear reactions that fuel the sun and other stars release an

enormous amount of energy• This energy is emitted as radiation of several kinds, including visible

light and the heat that warms the earth• UV light is a type of high energy (short wavelength) radiation that is

produced by the sun• There are three types of UV radiation: UVA, UVB, UVC

UV RADIATION IS THE MAIN CAUSE OF SKIN CANCER

Ultraviolet Radiation

UVA: Longest UV wavelength (400 - 315) nm• Can be harmful to humans• Very little absorbed by the atmosphere• Not absorbed by the ozone layer• Responsible for most sunburns• Penetrates deeper into the skin than other UV

wavelengths• Long term exposure can cause significant damage

to skin including blemishes, wrinkles and possibly cancer

Ultraviolet Radiation

UVB: Middle UV wavelength (315 - 280 nm)• May be harmful to humans• Approximately 90% absorbed by the atmosphere• Mostly absorbed by the ozone layer• Responsible for most sunburns• Penetrates skin and is absorbed by DNA• Causes DNA damage leading to cancer

UVC: shortest UV wavelength (280 - 100 nm)• Not harmful to humans• Completely absorbed by the atmosphere

Ultraviolet Radiation Other bad things from UV radiation

• Immune System Suppression (17)• Impairs the body’s ability to fight disease• May activate viruses already in skin• Can promote cancers and worsen infectious diseases caused by bacteria• Research is ongoing to discover more

• Eye Disorders (20)• Cataracts• Cancer of skin surrounding the eyes • Burns caused by overexposure to UV light• Macular degeneration: damage to the central part of the retina• Pterygium: non-cancerous growth on the corner of the eye that can

partially block vision

Electromagnetic Spectrum

Solar Radiation and the Earth’s Atmosphere

Vitamin D Vitamin D

The Sun and You Benefits of the SUN

• The sun triggers Vitamin D synthesis, which is good for the body• Only SMALL amounts of sunlight are needed (10-15 minutes;

NOT a suntan)• Vitamin D is found in foods such as eggs, fish, and cheese

American Cancer Society Recommendation“Slip! Slop! Slap! Wrap!”

Slip on a shirt, Slop on 15 SPF (or higher) sunscreen,

Slap on a hat, Wrap on sunglasses before any exposure to the sun.

* From ACS Skin Cancer Fact Sheet 2006

Prevention

Image courtesy of NASA

Prevention Limiting Exposure

• The sun’s UV rays are the strongest between 10 a.m. and 4 p.m., limit exposure to the sun during these hours if possible

• Exposure varies with times of the year and areas of the world• Sunny seasons provide the most UV exposure

Prevention: Sunscreen Reducing Risk While Being Exposed

• SUNSCREEN! Your personal ozone layer!• Blocks most UV radiation, although not all of it

• Different SPF numbers (Sun Protection Factors) • SPF 15, 30, 45, etc.• The higher SPF equals a longer period of protection • Sunscreen wears off, so it must be reapplied every few hours…especially

when sweating, swimming, or toweling off

Prevention “Most people benefit from sunscreens with sun protection factor

(SPF) numbers of 15 or more. The SPF number gives you some idea of how long you can stay in the sun without burning. For example, if you burn in 10 minutes without sunscreen and you apply a liberal dose with a SPF number of 15, you should be protected from sunburn for 150 minutes. Although sunscreens with identical SPF numbers give you equivalent sunburn protection from UVB rays, no sunscreen product screens out all UVA rays. Some may advertise UVA protection, but there is no system to rate UVA protection yet.” (4)

Prevention: SPF by the Numbers

SPF = number of minutes required to get the equivalent of 1 minute of unprotected exposure

Example: SPF 3030 minutes in the sun = 1 minute ofunprotected exposure (8)

Prevention

SUNSCREEN…USE IT!•“In 2003, only 14% of high school students

reported routine sunscreen or sunblock use with an SPF of 15 or higher when outside for more than 1 hour on a sunny day, and this rate has remained unchanged since 1999.” (18)

Prevention

Protective Accessories (8)• Clothing

» Provides UV radiation protection» Loose fitting, long-sleeved shirts and long pants made

from tightly woven fabric offer the best protection» Typical lightweight t-shirts worn in the summer

provide less protection than a sunscreen with anSPF of 15 or higher

Prevention

Protective Accessories (8)• Hats

» Hats can help shield your skin from the sun’s UV rays

» Wear hats with a brim that shades the face, ears, and the back of the neck

• Umbrellas» Must be opaque, not transparent

Tanning

Dangers of Tanning (5)• Causes skin cancer! • Cosmetic issues• Leathery skin, wrinkled skin• Can suppress the immune system• Premature aging of the skin

Tanning Truths

Some Tanning Truths• “Tanning not only increases the risk for melanoma

and squamous cell carcinoma, but accelerates skin aging”James M. Spencer, MD, director of dermatologic surgery at Mount Sinai Medical Center in New York City (12)

• Five or more sunburns doubles your risk of developing skin cancer (13)

Tanning Myths

Myth: Tanning is okay (5) Reality

• NO!• Tanning provides excessive exposure to harmful UV radiation, which

can cause skin cancer• “A tan is actually the result of skin injury…[w]hen a person's skin

darkens from a tan, it is an indication that damage has occurred to the skin and the skin is trying to protect itself by producing more pigment or melanin.” James Spencer, MD, FAAD, professor of clinical dermatology at Mount Sinai School of Medicine (6)

• Using tanning oil will not prevent sun damage

Tanning Myths

Myth: Tanning beds are safer than the sun Reality

• NO!• Most tanning bed lamps emit both UVA and UVB rays• A study from Dartmouth in 2002 showed tanning bed

users had 2.5 times the risk of SCC and 1.5 times the risk for BCC. (19)

• “Indoor tanning…is a dangerous practice leading to a vast array of adverse effects” (10)

UV Radiation Myths Myth: Clouds block UV radiation (16) Reality

• Not really • A thin layer of clouds can let up to 80% of UV rays through• A thick layer of cloud cover can block most but not all UV rays

Myth: Clothes block UV radiation (8) Reality

• Somewhat correct• A white, dry cotton shirt provides less protection than sunscreen

with an SPF of 15• Fabric that allows light through also allows UV ray’s through• Wet clothing allows about 50% transmission of UV radiation

 

UV Radiation Myths Myth: Water doesn’t reflect UV radiation (8) Reality

• Yes it does!• Sand and concrete reflect 15% of UV radiation• Water reflects less than 10% of UV radiation• Snow reflects 80% of UV radiation

Cancer Myths

Myth: Darker skinned people don’t get skin cancer Reality

• False!• They are at risk for skin cancer and most frequently at risk

for melanoma• Frequent areas from cancer in darker skinned people are

palms, soles, under nails, in the mouth, or on genitalia• NO ONE is 100% risk free from skin cancer

Check Yourself Before You Wreck Yourself

Be in tune with your body• Pay attention to things inside and out• As always, if you are unsure about something seek

professional help• A simple exam can be done to check for skin cancer

» Check all areas of the skin» Focusing on the face, arms, neck and torso

• Also, DON’T SMOKE it’s terrible for you!

References

1. Basal Cell Carcinoma. The Skin Cancer Foundation. 2006. http://www.skincancer.org/basal/index.php (accessed 6/12/06)

2. Squamous Cell Carcinoma. The Skin Cancer Foundation. 2006 http://www.skincancer.org/squamous/index.php (accessed 6/12/06)

3. American Cancer Society. Learn About Skin Cancer – Melanoma. 2007. http://www.cancer.org/docroot/lrn/lrn_0.asp

4. Sunscreens and Sun-Protective Clothing. Federal Trade Commission. May 2001. www.ftc.gov/bcp/conline/pubs/health/sun.htm (accessed 7/3/2006)

5. The Darker Side of Tanning. American Academy of Dermatology http://www.fda.gov/cdrh/consumer/tanning.html, (accessed 6/29/2006)

6. Innovative Public Service Advertisement Campaign Sends Strong Message To Teens About Dangers Of Indoor Tanning American Academy of Dermatology. October 19 2006. http://www.medicalnewstoday.com/medicalnews.php?newsid=54504 (accessed 11/13/2006)

7. American Cancer Society Cancer Facts and Figures, 2007. American Cancer Society Publication. Atlanta, GA. 2007.

8. American Cancer Society. Skin Cancer Prevention and Early Detection . http://www.cancer.org/docroot/PED/content/ped_7_1_Skin_Cancer_Detection_What_You_Can_Do.asp (accessed11/13/06).

9. Tanning Restrictions for Minors A State-by-State Comparison. March 2007. http://www.ncsl.org/programs/health/tanningrestrictions.htm

10. Jody A. Levine MD, Michael Sorace MD, James Spencer MD and Daniel M. Siegel MD. The indoor UV tanning industry: A review of skin cancer risk, health benefit claims, and regulation. Journal of the American Academy of Dermatology. Volume 53, Issue 6, December 2005, Pages 1038-1044.

11. Catherine A. Demko, PhD; Elaine A. Borawski, PhD; Sara M. Debanne, PhD; Kevin D. Cooper, MD; Kurt C. Stange, MD, PhD. Use of Indoor Tanning Facilities by White Adolescents in the United States. Arch Pediatric Adolescent Medicine. 2003;157:854-860.

12. The Skin Cancer Foundation. The Case Against Indoor Tanning. 2007. http://www.skincancer.org/artificial/index.php

References

13. Pfahlberg A, Kolmel KF, Gefeller O. Adult vs childhood susceptibility to melanoma: Is there a difference? Arch Dermatol, Sep 2002; 138: 1234 – 1235.

14. Vander's Human Physiology: The Mechanisms of Body Function, 10/e. Eric P. Widmaier, Hershel Raff, Kevin T. Strang. 2006. McGraw-Hill Inc: New York, New York.

15. Ries LAG, Harkins D, et al. SEER Cancer Statistics Review, 1975-2003, National Cancer Institute. Bethesda, MD. http://seer.cancer.gov/csr/1975_2003/, based on November 2005 SEER data submission, posted to the SEER web site, 2006.

16. Carolyn Strange. Thwarting Skin Cancer with Sun Sense. FDA Consumer Magazine (July-August 1995) http://www.fda.gov/fdac/features/695_skincanc.html (accessed 7/5/07)

17. Stephen E. Ulrich. Mechanisms underlying UV-induced immune suppression. Mutation Research (571) 185-205. 2005

18. Sherry Everett Jones, Mona Saraiya. Sunscreen Use Among US High School Students, 1999-2003Journal of School Health, April 2006, Vol. 76, 4, 150-153.

References

References

19. Margaret R. Karagas; Virginia A. Stannard; et al. Use of Tanning Devices and Risk of Basal Cell and Squamous Cell Skin Cancers Journal of the National Cancer Institute; Feb 6, 2002; 94, 3; Research Library pg. 224

20. World Health Organization. Global disease burden from solar ultraviolet radiation. http://www.who.int/mediacentre/factsheets/fs305/en/index.html