Dear Dr. K,
My 82-year-old mom's doctor ordered a mammogram and pap recently even though she has pretty significant dementia. I'm not sure she would even understand a cancer treatment if a problem were found. Are these tests really necessary?
Probably not. Recent studies and expert guidelines have suggested that it's often appropriate to dial back on cancer screening as people age, especially if they have dementia or another condition that's likely to limit life expectancy. Plus, as you so perceptively point out, in the case of Alzheimer's or other dementias, cancer treatments can be a particular ordeal, since the patient often doesn't understand why uncomfortable treatments and procedures are being done.
Ideally, the decision to refer an older woman for cancer screening would be made after the doctor and patient had considered the overall health state of the patient and agreed that the benefits of screening were likely to outweigh the burdens.
Unfortunately, this kind of individualized decision-making process seems to reflect the exception rather than the rule. This is probably due to issues like lack of time during primary care visits, force of habit among both doctors and patients, and the fact that doctors' practices are sometimes graded on their cancer screening rates.
The upshot is that many elderly patients still end up being referred for cancer screening, even when screening isn't recommended, based on the usual guidelines. (Note: these are guidelines are usually intended for use with patients who are otherwise relatively healthy.) In the case of breast cancer screening, the American Geriatrics Society recommends offering screening every 1-2 years for older women who are likely to live 4 or more years. For Pap smears, most expert groups have concluded that it's okay to stop in women who have had at least three normal paps over the previous 10 years and are older than 70.
Personally, I would only refer a patient like your mother for cancer screening upon request from family, and even then, I'd only do it after we'd spent time together reviewing the guidelines and the low chance of benefit. It's unlikely she would benefit from either test. Most caregivers, after learning more, opt to skip the cancer screening. But every now and then, a family feels very strongly that even a 1-in-240 (or less, in the case of dementia) chance of benefit is worth it. The key is to be informed, before proceeding.
My prescription for caregivers about cancer screenings in older patients:
"¢ Know that expert groups agree that cancer screening can often be stopped as people age, especially if there's a diagnosis of dementia or other health problems likely to limit life expectancy. For example, for adults older than 75, many expert guidelines support stopping routine screening for breast, cervical, colon, and prostate cancer. "¢ Discuss with the doctor screening on an individualized basis that incorporates a person's life expectancy, health status, and preferences. "¢ Make it a habit to ask the doctor to clarify the likelihood of benefits and harms, when a loved one is referred for a test or procedure. Often caregivers discover that the chance of directly benefiting from screening is smaller than they had expected.