How much do you know about skin cancer?

To test your knowledge, the American Academy of Dermatology has designed the following quiz. Answer true or false for each question and then check your results below. QUESTIONS:

1. Skin cancer is the most common type of cancer in the United States.T F

2. An open sore or wound that doesn't heal for weeks may be a sign of skin cancer.T F

3. One out of every 10 Americans suffers from some type of skin cancer.T F

4. All skin cancers are called melanoma.T F

5. The sun's rays are more harmful to your skin at 2 p.m. than at 8 a.m.T F

6. People with dark skin rarely get skin cancer.T F

7. Lip cancer is less common in rural areas.T F

8. Everyone has moles, often 40 or more.T F

9. It's difficult to get a sunburn on hazy, cloudy days.T F

10. Medical research shows that there is no connection between exposure to the sun and the most serious life-threatening form of skin cancer, malignant melanoma.T F

11. Hardly anyone dies from skin cancer.T F

12. Blacks are 10 times more likely to develop malignant melanoma than whites.T F

13. Number 8 SPF (sun protection factor) is the highest-rated sun block available on the market.T F

14. Birth control pills can increase one's sensitivity to the ultraviolet radiation from the sun, leading to a more painful and damaging sunburn than one would get otherwise.T F

15. Certain types of radiation from tanning parlors are safe for skin.T F

16. Moles with ill-defined or irregular borders may be a warning sign of skin cancer.T F

17. The cure rate for skin cancer is 100 percent if detected and treated in time.T F

18. Malignant melanoma increases as you get closer to the equator.T F

19. Tucson, Ariz. has the highest incidence of malignant melanoma in the United States.T F

20. Since 1950, the number of deaths from malignant melanoma have quadrupled among men and tripled among women. ANSWERS:

1. True. One out of every three cancers diagnosed in the United States today is a skin cancer.

2. True. If a sore persists or heals and then reopens, see a dermatologist or your family physician.

3. False. Even more Americans -- one of every seven -- suffer from skin cancer.

4. False. There are several types of skin cancers. The three most common are basal cell carcinoma, squamous cell carcinoma and malignant melanoma, the most deadly kind.

5. True. The sun's rays are most intense and dangerous from 10 a.m. to 2 p.m. At those hours, the rays pass through less ozone, the protective atmospheric layer between you and the sun.

6. True. Darker skinned people have more melanin, a brownish pigment in the skin, which serves as a buffer by absorbing ultraviolet rays, and thus lowers the risk of skin cancer.

7. False. Lip cancer is more common in rural areas, where people work outdoors and have more exposure to the sun.

8. True. Moles come in various sizes and shapes, singly or in groups, and can appear anywhere on the skin. Most make their appearance in the first 20 years of life.

9. False. It's easy to get sunburn on a cloudy day because up to 80 percent of the sun's rays penetrate the clouds. People feel cooler on days when clouds filter out the heat -- causing prolonged suntanning and increased risk of excessive exposure.

10. False. There is a strong correlation between overexposure to ultraviolet radiation from the sun and the incidence of malignant melanoma, a relatively uncommon but deadly form of skin cancer.

11. False. Last year, approximately 5,500 Americans died from malignant melanoma.

12. False. The reverse is true. Whites are 10 times more likely than blacks to develop melanoma.

13. False. The American Academy of Dermatology suggests a sunscreen of 15 or more SPF (sun protection factor) for maximum protection. Sunscreens should be reapplied if one is perspiring heavily or swimming.

14. True. Certain medications including tranquilizers and oral contraceptives are phototoxic -- they can cause unpleasant reactions to ultraviolet radiation from the sun, ranging from mild rashes and headache to nausea and vomiting.

15. False. Radiation from tanning parlors is as dangerous as the rays from the noon sun in summer.

16. True. Other warning signs are: a sudden enlargement in the diameter of a mole (in excess of six millimeters); a sudden darkening of a mole or mixed shades of red, blue and white, persistent pain or itchiness; surface characteristics such as scaliness, crusting, ulceration or bleeding.

17. True. Since early detection is critical, regular self-examination and physician examination of the skin is critical.

18 and 19. True. Population studies show that the incidence of malignant melanoma is related to geographical location. Persons in southern latitudes, where ultraviolet radiation from the sun is more intense, are more likely to develop melanoma than those residing in northern climates.

20. True. These mortality figures were compiled by the National Center for Health Statistics. This increase is thought to be related to greater sun exposure.