Cancer Screening: Who to Screen and When to Stop

More than 1 in 10 Americans over age 60 years will be diagnosed with cancer, according to the National Cancer Institute, making screening for the disease in older patients imperative. Much of the burden of cancer screening falls on primary care physicians. American Cancer Society are giving a lot of thought to how to help primary care practices keep up with the screening, particularly with respect to guidelines, but also best practices where judgment is required, such as cancer screening in the older patients.

Data shows cancer rates are going up. With respect to guidelines for cancer screening, a good physician uses a best judgement. For example, in young women, Breast cancer screening for the ones who have BRCA gene, if they have dense breast, or if they have a strong family history of breast cancer should be different from those who are at average risk of the disease. For colorectal cancer screening, the ACS dropped the age to begin screening to 45 and 2018 based on a very careful consideration of disease burden data and most other guideline developers reach the same conclusion.  

There is something called multi cancer early detection or MCED tests which is in development and undergoing prospective research. It is utilized for cancer screening. The blood sample is tested for certain pieces of DNA or proteins from cancer cells. MCED tests might be able to find a wide range of cancers earlier, hopefully before a person has any symptoms. However there is going to be a need for expertise in primary care practice to help interpret these tests which are well beyond what even the typical oncologist is treated in.

We know that cancer risk does obviously increase with age, particularly prostate and breast cancer. There’s very little data from Randomized clinical trials of screening people over the age of 70. My philosophy on cancer screening is that I think guidelines are guidelines. If patient have very limited life expectancy, then they shouldn’t be screened. However, if their life expectancy is longer than 10 years, then all things being equal, they should continue screening, but the question of ongoing screening needs to be periodically revisited.