If you seriously think this is a realistic scenario, you should call your doctor and tell him you've decided you have cancer and would like to order chemotherapy. See what he says.

Nobody is deciding for themselves to do chemo because they think something looks funny on a scan. All the scan gives them is a reason to talk to their doctor, who will do all the usual due diligence before deciding on treatment, if any.

And on the flip side, I hear stories all the time of people who DO have symptoms but they get dismissed by their doctor as stress or food allergies or whatever until it's too late. Maybe if patients were armed with a scan that shows a mass at the site of their abdominal pain, there would be fewer of these horror stories.