Early cancer detection is terrific if you have an aggressive cancer that can kill you, such as lung, bowel or breast cancer. But there are cancers that are present in your body (everyone has them) that may never grow into aggressive cancers. We know this because, for example, most men over the age of 50, will have a cancer in their prostate that do not show up on any testing and would only show up on an autopsy if they should die and have one. Even when the cancer test used to detect the ‘prostate specific antigen’ (PSA is detected as abnormally high, many of these men who previously would have radical surgery for it, today are told not to do it because the complications of the surgery, radiation or other treatments out way the risks of disease progression in most men. Even breast cancer is present in many women with what we call ‘cancer in-situ’ which means that these cancers would show up on a biopsy (if it could be found) or on an autopsy (if a person had it as an incidental finding on death). We are now developing better and better tests to pick up cancer, but are we going to over-react to these ‘pick-ups’?
Websites that market personalized cancer care early often overemphasize their stated benefits and downplay their limitations and certainly don’t focus upon the risks of treatment for very early cancers ‘in-situ’. Genetic tests whose value for guiding cancer treatment have not been shown to be clinically useful in many situation. Should everyone get a complete copy of their DNA and have it analyzied for cancer potential genes that they may harbor? Finding a cancer and suggesting an aggressive action may be harmful because it may have an unproven benefit.
“Internet marketing of cancer-related gene tests is unregulated so there is wide variation in how these services are presented, posing a challenge for consumers and their physicians, notes Stacy Gray, M.D., a medical oncologist and investigator at the Dana-Farber Center for Outcome and Policy Research and first author of the paper that analyzes 55 websites marketing the services. The study found that “in general, the benefits of these personalized cancer products are reported much more frequently than are the limitations,” continued Dr. Gray. In addition, 88% of the websites offered one or more “nonstandard” tests that lacked evidence of clear clinical utility in routine oncology practice.
A friend of mine, called me and told me that her Chest X-ray and a follow-up CAT scan showed a nodule in her lung that would be a cancer. One doctor told her to come back in 3 months and repeat the CAT scan, so she did and it was still there. She does not sleep at night worrying about it. She can address it with a surgery. IF the nodule is under 1cm, in the outer part of the lung and she has surgery and they find a cancer, she has an 80% risk of cure. If she waits, and she has a cancer and it grows, then her risk of cure goes down to under 30%. IF she has a surgery and does not have cancer, then she underwent an unnecessary surgery that she can ill afford.
As President Obama’s personalized medicine initiative rolls out, more and more information about potentials for cancer will unfold in us all. How do we respond if we know that we have a ‘cancer in-situ’? Do we demand a radical treatment such as surgery for something that may never develop to a dangerous level? Do we stand-by and wait, missing those cancers that are aggressive and can kill us? There is no clear answer to these questions, but the public generally does not understand that this is not an easy process to analyze.