Because a routine physical examination is not covered by the B.C. Medical Services Plan in a patient with no symptoms and no known disease, most adults are not aware of all the screening tests they should consider.
Screening tests are recommended for the early detection and treatment of particular medical conditions in individuals of average risk and with no symptoms.
For example, the stool occult blood test (FOBT or FIT) is recommended as a screen for colon cancer for adults over 50 years every 2 to 3 years. If it is positive (indicating a source of bleeding in the gastrointestinal tract), the next test is usually a colonoscopy (in which a flexible scope is inserted into the anus and used to see and remove polyps and other growths in the large intestine).
However, if an older adult has obvious blood in his stools, his physician will likely arrange a colonoscopy without the need for a positive stool occult blood test. If another individual with no symptoms has a family history of colon cancer, the first surveillance colonoscopy should begin at an age 10 years before the age at which the relative was diagnosed. For example, if a woman’s father was diagnosed with colon cancer at age 52 and her sister was diagnosed at age 48, she should have her first colonoscopy at age 38.
These are the screening tests for other conditions.
High Blood Pressure For adults 18 and older, blood pressure should be measured at every appropriate medical visit (e.g. annually). Once hypertension or high blood pressure is identified, the patient and doctor will discuss the appropriate frequency of rechecking blood pressure.
Cervical Cancer The pap smear is a sample of cervical cells taken during a pelvic examination, but please note that a pap smear is not necessarily done with every pelvic exam, which may have been necessary for pelvic pain or a possible infection. A woman should always clarify with her physician what tests were done during each examination.
Women should start pap smears at age 25 and continue at a frequency of every 3 years (or more frequently depending on the recommendations of the BC Cancer Agency which interprets the pap smears and sends reports to the physician). Women 70 years and older may stop screening after 3 successive normal paps in the previous 10 years.
Diabetes The fasting glucose blood test was formerly recommended as the screening test for adults over age 40. The confirmatory test was the 2-hour 75 gm glucose tolerance test.
The newest recommendation is the Hb a1c blood test only in high risk and very high risk patients based on the FINDRISC or CANRISK calculators. Those found to be high risk for diabetes should be screened every 3 to 5 years; those at very high risk every year.
Breast Cancer Monthly self-examinations and annual clinical examinations by physicians are no longer recommended. Screening mammograms are now the only remaining screening test and the Canadian guidelines recommend them every 2 years in women from age 50 to 70.
Prostate Cancer The standard screening test is the annual DRE (digital rectal examination). Don’t be fooled by the name; it’s not high tech imaging. It’s high touch with your doctor’s gloved finger checking the size and shape of the prostate. My patient, Tom calls it the fickle finger of fate.
This is not the right time to ask your doctor for a second opinion.
Doctor (as he snaps off his glove): You have a huge prostate and you need surgery.
Patient: Can I have a second opinion?
Doctor: You already did. I used two fingers and they both feel the same.
The PSA (prostate specific antigen) is a blood test to detect levels of a protein produced by the prostate. It may be elevated by benign enlargement of the prostate or by prostate cancer. It is not recommended as a routine screening test for men at any age. Men should discuss the value of this test with their physicians as it has to be interpreted in conjunction with the rectal examination.
The PSA is not recommended as a screening test because an abnormal test may result in investigations and treatment that may cause more harm than a slow growing prostate cancer that may not otherwise affect the patient.
Dr. Davidicus Wong is Physician Lead of the Burnaby Division of Family Practice. A poster of these screening tests can be found at divisionsbc.ca/burnaby. For more information on screening tests, see the Canadian Task Force on Preventive Health Care http://canadiantaskforce.ca