Health Screening Flashcards
What is lead-time bias?
An apparent increase in the length of survival in patients with a disease as a result of earlier detection through the use of a screening program
What is length-time bias?
Preferential detection of less aggressive forms of a disease though screening programs
- Less aggressive forms will grow slowly and patient will have longer before clinical signs show, giving much more time to detect
Is the use of digit rectal exam useful as a SCREENING test for prostate cancer?
- No
- Poor Sensitivity (59%)
- Specificity not well known
- Reproducibility of test is poor
Is the use of PSA recommended as a screening test for prostate cancer?
- No
- Only 1 death will be avoided per 1000 people screened
- 100-120 will have false positives requiring biopsy
- 29 will develop E.D. due to treatment
- 18 will develop urinary incontinence due to treatment
What is hereditary nonpolyposis colorectal cancer? What is it now called?
- Lynch syndrome
- Autosomal dominant mutation that increases risk of cancer
- Colon and endometrial cancers most common
- Tend to occur at younger age (under 50)
Who is at average risk of colorectal cancer?
- People aged 50-74 with no 1st degree relative w colorectal cancer
- No history of previous polyps or inflammatory bowel disease
How and how often should someone at average risk of colorectal cancer be screen according to cancer care ontario?
- FOBT every 2 years in those who are asymptomatic
- If abnormal will have colonoscopy within 8 weeks
- Can choose to do flexible sigmoidoscopy as well which should be done every 10 years if normal
Who is at increased risk of colon cancer?
- Those with family history of 1st degree relative diagnosed with colorectal cancer
When and how should someone at increased risk for colorectal cancer be screened if asymptomatic?
- Screen with colonoscopy
- Start screening at age 50 or 10 years before the age their relative was diagnosed depending on which is sooner
