Cancer screening is the process of checking for cancer when there are no symptoms. The methods used to detect cancer are often called screening tests and are a great step towards cancer prevention. Some types of screening tests performed by our cancer specialists and cancer doctors include:
Inspections of specific areas of the body used to help detect abnormalities (e.g., clinical breast examination for breast cancer, digital rectal examination for prostate and rectal cancers).
Tests that produce pictures of areas within the body, (e.g., x-ray, mammography for breast cancer).
Tests that check; blood, urine, and other body fluids and tissues (e.g., fecal occult blood test for colorectal cancer, Pap test for cervical cancer).
People who are at increased risk for certain cancers may need to follow a different screening schedule, such as starting at an earlier age or being screened more often. Those with symptoms that could be related to cancer should see their cancer doctor right away.
The following cancer screening guidelines are recommended for those at average risk for cancer (unless otherwise specified) and without any specific symptoms.
For people aged 20 or older having periodic health exams, a cancer-related checkup should include health counseling, and depending on a person's age and gender, might include exams with a family or for cancers of the thyroid, oral cavity, skin, lymph nodes, testes, and ovaries, as well as for some non-malignant (non-cancerous) diseases. Your doctor will help you determine the tests you should have.
Special screening guidelines for certain cancer sites are recommended as outlined below.
Breast Cancer Screening Guidelines
The lifetime risk (to age 85) of a woman developing breast cancer in 1940 was 5% or 1 in 20; the risk is now 12.6% or 1 in 8. In women 40-49 years of age there is a 1 in 66 risk of developing breast cancer compared with a 1 in 40 risk among women in the 50-59 year age group.
Randomized controlled trials have demonstrated reduced mortality rates (20-40%) from breast cancer among women invited to undergo screening mammography compared with control groups.
Although statistically significant benefits/reductions in breast cancer mortality are delayed 10 to 15 years among women 40-49 years of age at the time of screening, several of the screening trials have reported a benefit (23-44%) from screening women 40-49 years of age.
The benefit of mammography is related to early detection. Regardless of the histological grade of a tumor, a greater than 90% ten year survival has been reported in 40-74 year old women diagnosed with tumors that are 10 mm or smaller in size.
The effectiveness of any screening program will depend on screening frequency, compliance with screening recommendations and the quality of the screening test.
In establishing screening frequencies, breast cancer growth rates need to be considered. The sojourn time (average time for mammographically detectable, preclinical cancers to become clinically apparent) for all breast cancer types is shorter for pre-menopausal women compared with post-menopausal women supporting annual screening in 40-49 year old women: 1.8 years in 40-49 year old women and 3.5 years in women 50 years of age or older.
Women should perform a monthly breast self-examination starting at age 20.
Although monthly breast self exams have not been proven to reduce the death rate from breast cancer, it is often a lump or other change that a woman notices in her own breast. Because this free test is the way in which many breast cancers are detected, and because it is important that women become familiar with the way their breasts feel a monthly breast self-exam is recommended for all women beginning at the age of 20.
Other screening guidelines include:
- Annual breast physical examination by a health care provider starting at age 40.
- Annual screening mammography starting at age 40. The frequency of screening for women between the ages of 40 and 49 may be decreased to every two years if determined appropriate by both the patient and physician.
- Women in high-risk categories (first degree relative with breast cancer; personal history of breast cancer; prior biopsy with atypical ductal hyperplasia or lobular carcinoma in situ) may want to consider starting screening at age 30.
Cervical Cancer Screening Guidelines
Cytologic screening (Papanicolaou or Pap smears) represents one of the most successful screening efforts of modern medicine. The morbidity and mortality secondary to cervical cancer has substantially decreased in adequately screened populations. Patients, however, need to understand that Pap smears are intended to be a "screening" not a "diagnostic" test. For any screening test there is an inherent false negative rate which is approximately 10 to 20% for Pap smears. In spite of the false negative tests, the success of the cervical cytology screening program has led patients to expect 100% accuracy. This has produced a flurry of medicolegal action and governmental regulations leading to a substantial increase in the cost of and the introduction of expensive new technologies of unproven benefit. Patients need to understand that because of the screening nature of Pap smears, successful screening requires multiple repeat examinations and a minimization of risk factors.
Recommendations for Cervical Cancer Screening
Low risk patients
- Sexually active or 18 years of age and no increased risk factors
- Pap smear for three (3) consecutive years
- After three satisfactory, normal annual Pap smears - Pap smear every 3 years
- Age 60 with regular prior negative screening tests and no increased risk factors
- Discontinue screening
- Hysterectomy for benign gynecologic disease
- Discontinue screening
Increased risk patients
- Annual Pap smear
- Annual pelvic exam
Increased risk is defined by the presence of any one of the following:
- Infection with certain types of human papilloma virus (HPV)
- HIV - positive
- Cigarette smoking
- Multiple sexual partners
- Prior abnormal Pap smear or cervical dysplasia
Colorectal Cancer Screening Guidelines
Cancer of the large bowel (the colon and rectum) is the third most common form of cancer in the United States, diagnosed in 130,000 Americans annually. Fortunately, with advances in early detection and treatment, colorectal cancer is one of the more curable forms of the disease. Most early forms of colon and rectal cancer cause no symptoms, which makes screening especially important. When symptoms do occur the cancer may already be quite advanced.
Although there are many types of colorectal polyps only adenomas are associated with an increased risk of colorectal cancer. Adenomatous polyps are pre-cancerous (benign) growths on the lining of the colon and rectum. Almost all colorectal cancers begin as an adenomatous polyp, a growth in the tissues lining the colon and rectum. Cancer develops when these polyps grow and their cells start to invade surrounding tissue. Removal of polyps can prevent the development of colorectal cancer. Pre-cancerous polyps can be removed painlessly using a flexible lighted tube called a colonoscope. If caught in its early stages, cancer of the colon and rectum is curable in over 90% of patients.
We would recommend the following screening guidelines for colorectal cancer in the general population beginning at age 45
- Colonoscopy every 10 years OR
- Yearly stool test for blood (hemoccult) and a flexible sigmoidoscopy every 5 years.
While all Americans are at risk for getting cancer of the colon and rectum, some people are at particularly high risk. For those people, screening for colon cancer should be more frequent and include a full colonoscopy.
There are two main risk factors to consider: Personal history of colorectal polyps or cancer and family history of colorectal polyps or cancer. If you have a family history of colorectal cancer, your risk and the screening recommendations will depend on how many people in your family are affected and at what age they were diagnosed. Below are listed the levels of risk according to personal or family history and the screening recommendations.
History Category Screening Recommendations
Your risk is not significantly different than the average population.
- Age 45 without a personal or family history of colorectal adenomatous polyps or cancer OR
- One cousin, aunt, uncle or grandparent with colorectal adenomatous polyps or cancer.
Screening Recommendation: A colonoscopy every 10 years beginning at age 45 is preferable. The alternative would be a yearly stool test for blood (hemoccult) and a flexible sigmoidoscopy every 5 years.
Your risk for colon cancer is approximately twice the average risk.
- One parent, brother or sister with colorectal polyps or cancer who was diagnosed older than age 60.
Screening Recommendation: Colonoscopy every 10 years (as described above) beginning at age 40.
- Personal history of adenomatous polyps or cancer Or
- One parent, brother, sister or child with colorectal cancer or adenomatous polyps, who was diagnosed at age 60 or less Or
- Two first degree relatives (on same side of family) with colorectal cancer or adenomatous polyps (parent, brother or sister or child).
Screening Recommendation: Colonoscopies at intervals dependent on size, number and pathology of polyps found on prior colonoscopy.
- Three or more relatives with colorectal adenomatous polyps or cancer, especially if one is age 50 or less at diagnosis.
Screening Recommendation: Colonoscopy beginning 10 years earlier than the age at which your youngest relative was diagnosed, or when you are age 40, whichever is younger. Interval is every 5 years or earlier dependent on findings of the colonoscopy. If you are at high risk, you should be assessed by specialists in inherited syndromes and have genetic counseling. You may be eligible for testing to see if you have inherited a gene that puts you at risk for colon cancer. Screening recommendations will be provided as part of your assessment.
Note: If you have a personal history of colorectal polyps or cancer and a family history in any category you may be at high risk. Consider contacting the Hereditary Colon Cancer Registry, a family coordinator will arrange an appointment in the Center for Personalized Genetic Healthcare. Call 216.445.2050 or 800.223.2273 ext. 5-2050
Prostate Cancer Screening Guidelines
While there is no information yet available that can tell us whether screening for prostate cancer makes a difference in how long a patient will live after his prostate cancer is discovered, we still recommend following screening guidelines.
Recommendations for Prostate Cancer Screening according to physicians at the Cleveland Clinic
The following should be offered annually:
- Annual digital rectal exam (DRE) and PSA counseling for all men beginning at age 45 - 50 who have at least a 10-year life expectancy.
- Annual DRE and PSA counseling beginning at age 40 for African-Americans and those with a positive family history of prostate cancer.
The American College of Physicians recommends that all men who are considering DRE and PSA counseling should consider the following:
- The benefits of one-time or repeated screening and aggressive treatment of prostate cancer have not yet been proven.
- Digital rectal examination (DRE) and PSA measurement can both have false-positive and false-negative results.
- The probability that further invasive evaluation will be required as a result of testing is relatively high.
- Aggressive therapy is necessary to realize any benefit from the discovery of a tumor.
- A small risk for early death and a significant risk for chronic illness, particularly with regard to sexual and urinary function, are associated with these treatments.
- Early treatment may save lives.
- Early detection and treatment may head-off future cancer-related illness