Screening for cancer is examination (or testing) of people for early stages in the development of cancer even though they have no symptoms. Scientists have studied patterns of cancer in the population to learn which people are more likely to get certain types of cancer. They have also studied what things around us and what things we do in our lives may cause cancer. This information sometimes helps doctors recommend who should be screened for certain types of cancer, what types of screening tests people should have, and how often these tests should be done. Not all screening tests are helpful, and most have risks such as scar or infection after a biopsy for a suspicious skin nodule or mole. For this reason, scientists at the National Cancer Institute are studying many screening tests to find out how useful they are and to determine the relative benefits and harms.
If your doctor suggests certain cancer screening tests as part of your health care plan, this does not mean he or she thinks you have cancer. Screening tests are done when you have no symptoms. Since decisions about screening can be difficult, you may want to discuss them with your doctor and ask questions about the potential benefits and risks of screening tests and whether they have been proven to decrease the risk of dying from cancer.
If your doctor suspects that you may have cancer, he or she will order certain tests to see whether you do. These are called diagnostic tests. Some tests are used for diagnostic purposes, but are not suitable for screening people who have no symptoms.
The purposes of this summary on skin cancer screening are to:
You can talk to your doctor or health care professional about cancer screening and whether it would be likely to help you.
The skin is the body’s outermost covering and offers protection from heat and light, injury, and infection. It also helps regulate body temperature and stores water, fat, and vitamin D. The skin is made up of 2 main layers: the outer epidermis and the inner dermis.
There are 3 main types of skin cancer: basal cell carcinoma and squamous cell carcinoma (which are referred to as nonmelanoma skin cancer) and melanoma. Melanoma is the rarest and most serious form of the disease. The epidermis is made up of squamous cells, basal cells, and melanocytes. Melanocytes are the cells from which melanoma begins to develop.
Skin cancer is the most common form of cancer in the United States.
Anything that increases a person’s chance of developing a disease is called a risk factor. Some of these risk factors for skin cancer are as follows:
Race: Skin cancer is most common among fair-skinned individuals who sunburn or freckle easily.
Sex: Rates of skin cancer deaths in white males have increased in recent years, possibly as a result of the increase in outdoor recreation activities.
Age: Rates of melanoma rise rapidly in Caucasians older than 20 years.
Individual History: Persons with certain types of moles or those with a family history of dysplastic nevus syndrome are at a higher risk for developing melanoma. Patients who have had nonmelanoma skin cancer are at a higher risk for developing the disease again. Individuals who are exposed to the sun, x-rays, or ultraviolet light for long periods of time have a greater risk.
Routine examination of the skin increases the chance of finding skin cancer early. Most melanomas that appear in the skin can be seen by the naked eye. If an area on the skin looks abnormal, a biopsy is usually done. The doctor may remove all or part of the growth. To check for cancer cells, the tissue is looked at under a microscope by a pathologist. Because melanoma can be hard to diagnose, you should consider having your biopsy sample looked at by a second pathologist.
Usually, there is a lengthy period when the tumor expands beneath the top layer of skin but does not invade the deeper skin layers. This period allows for early detection and full recovery if the tumor is discovered before spreading deeper.
The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
Editorial changes were made to this summary.
If you have questions or comments about this summary, please send them to Cancer.gov through the Web site’s Contact Form. We can respond only to email messages written in English.
For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 9:00 a.m. to 4:30 p.m. Deaf and hard-of-hearing callers with TTY equipment may call 1-800-332-8615. The call is free and a trained Cancer Information Specialist is available to answer your questions.
Web sites and Organizations
The NCI's Cancer.gov Web site provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. There are also many other places where people can get materials and information about cancer treatment and services. Local hospitals may have information on local and regional agencies that offer information about finances, getting to and from treatment, receiving care at home, and dealing with problems associated with cancer treatment.
The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237), TTY at 1-800-332-8615.
The NCI's LiveHelp service, a program available on several of the Institute's Web sites, provides Internet users with the ability to chat online with an Information Specialist. The service is available from 9:00 a.m. to 10:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.
For more information from the NCI, please write to this address:
PDQ is a comprehensive cancer database available on Cancer.gov.
PDQ is the National Cancer Institute's (NCI's) comprehensive cancer information database. Most of the information contained in PDQ is available online at Cancer.gov, the NCI's Web site. PDQ is provided as a service of the NCI. The NCI is part of the National Institutes of Health, the federal government's focal point for biomedical research.
PDQ contains cancer information summaries.
The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries are available in two versions. The health professional versions provide detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions provide current and accurate cancer information.
The PDQ cancer information summaries are developed by cancer experts and reviewed regularly.
Editorial Boards made up of experts in oncology and related specialties are responsible for writing and maintaining the cancer information summaries. The summaries are reviewed regularly and changes are made as new information becomes available. The date on each summary ("Date Last Modified") indicates the time of the most recent change.
PDQ also contains information on clinical trials.
People who are at high risk for a certain type of cancer may want to take part in a clinical trial. A clinical trial is a study to answer a scientific question, such as whether a method of finding cancer earlier can help people to live longer. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients and those who are at risk for cancer. During screening clinical trials, information is collected about screening methods, the risks involved, and how well they do or do not work. If a clinical trial shows that a new method is better than one currently being used, the new method may become "standard."
Listings of clinical trials are included in PDQ and are available online at Cancer.gov. Descriptions of the trials are available in health professional and patient versions. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237); TTY at 1-800-332-8615.Physicians version: CDR0000062750