You notice a spot on your leg that wasn't there before and quickly head off to the dermatologist to find out what is going on. After an examination, your doctor tells you it is a "precancerous lesion." What does that mean? Does it mean it is only a matter of time until you develop cancer? Does it mean you need immediate treatment? Does it mean that you are okay and don't need to do anything?
According to DermIS, a precancerous lesion is "a change in some areas of your skin that carries the risk of turning into skin cancer. It is a preliminary stage of cancer."  Although not all precancerous lesions turn into cancer, many doctors treat these lesions proactively, removing the lesion before it has a chance to turn into cancer.
Some of the most common types of precancerous lesions are:
Acitinic Keratosis is the most common type of precancerous lesion. They usually appear in areas of the body that have been exposed to the sun. These lesions often appear as red or flesh colored scaly areas or could look similar to a wart. The surface may feel rough and dry. You may not notice the bump until you feel the scales. Around 5 percent of acitinic keratosis lesions turn into squamous cell carcinoma.
Moles are another common precancerous lesion. Most moles are benign skin growths. However, moles can develop into cancer over time. If you notice moles that change in color, have a uneven border or becomes larger, you should talk with your dermatologist. The more moles you have, the greater the chance one or more moles will develop into cancer. Taking pictures of your moles and comparing them over time can help quickly identify any changes.
Acitinic Chelitis is similar to acitinic keratosis but dry, scaly patches appear on the lips. Your lips may feel continuously cracked and chapped with small, dry patches. You may also notice some swelling of your lips or more defined lines. Any changes in your lips should be discussed with your dermatologist.
Cutaneous horns may also signal a higher risk of developing cancer. these are growths that extend outward and resemble a horn. They are most common in the elderly and those with fair skin.
Whether your precancerous lesion requires medical attention should be decided by you and your medical doctor. Many doctors will remove these lesions to lessen the chance of cancer developing. Removal may be by cryosurgery (freezing), excision, electrical currents or laser surgery, depending on the type of precancerous lesion you have. Your doctor may decide to do a biopsy of the lesion as well. For lesions your doctor is confident will eventually turn into cancer, more aggressive treatments, such as chemotherapy or radiation, may be suggested.
Dr. Kevin Berman, a Health Central expert, discusses monitoring precancerous lesions for signs they may be evolving into cancer in his article, "How to Know if Your Pre-Cancer is Now a Cancer."
"Actinic Keratosis," Date Unknown, Staff Writer, Skin Cancer Foundation
"Actinic Keratosis (A Precancerous Condition), Date Unknown, Staff Writer, John Hopkins Medicine
 "Precancerous Lesions," Date Unknown, Staff Writer, Skincancer.dermis.net
"Precancerous Skin Conditions," Reviewed 2012, Sept 29, Reviewed by Harvey Simon, M.D. and David Zieve, M.D., A.D.A.M. Medical Encyclopedia
"Precancerous Skin Lesions," Date Unknown, Staff Writer, South Shore Dermatology
"Telling the Difference Between Precancerous Skin Lesions and Normal Age Spots," 2012, Aug 19, Courtney Humphries, Boston.com