i believe when a person reaches an advanced age such as age 80 or older that he or she should have a discussion with his or her primary care provider about what screening tests still are necessary to undergo. (a related question for you: is a mammogram necessary at age 86? ) the answer to your question lies in many individualized factors such as how healthy and robust the 86 year old woman in question is. if she's very healthy and active and wishes to remain so then she may choose to undergo a colonoscopy test. if she's frail and has many other health problems then she may choose not to undergo colonoscopy. the purpose of colonoscopy is to detect precancerous polyps at an early stage in order to remove them. colonoscopy is recommended once every 10 years for people at an "average risk" for colon cancer. ultimately if the 86 year old woman in question is of sound mind she is entitled to make her own informed decision about whether or not to have a colonoscopy at her age. a medical professional should provide her with an unbiased assessment of the risks and benefits of such a test. the rigors and possible side effects of the colonoscopy prep should be discussed. i hope this helps!
age limit for colonoscopy test? . necessity for 86 year old woman to have test?