I had a call from a physician asking me to see him as he wanted to do CT scan of the chest due to so called new recommendation on doing low dose radiation CT scan to diagnose cancer of lung . Several years ago we started doing CT scan of chest in current smokers and Ex smokers for 14 years to diagnose cancer of lung early . There was new article and some added changes but overall it is about the same . But since it appeared in Newspaper, he wanted to get it done . He had quit smoking 30 years ago and he would not fall in to the recommended patients that would qualify for the CT scan.But that brings me to the story for today.
I had seen this patient for last 3-4 years .She is 74 years old female who had smoked for many years and had quit several years - 18 years ago. She had bad emphysema and needed oxygen and had not much of wheezing. She had shortness of breath and I had done CT scans and she had some small nodule . We followed the CT scan for 3 years and there was no change in tiny nodules and the radiologist felt that it was benign.The last scan was 8 or 9 months ago and I had plan to do yearly scan.She saw me and had pain in belly and so I told her to see Gastroenterologist and also to talk to primary care physician. I told her to take antacid and also ordered a chest X- ray . The chest X- ray was reported as normal. She continued to have pain and the gastroenterologist could not see her for 4 weeks or more and so when she still had pain ,she went to walk in clinic and they did CT SCAN of chest and also belly. The Ct scan of belly showed masses in liver and the lungs had nodules that we had seen and also had some lymph node enlargement . She was admitted and then we did further work up . We did the PET SCAN and that showed that the liver spots were hot and the lung nodules were warm not very hot . There was some uptake in lymph nodes in chest but again not very high . So we did the liver biopsy. The biopsy showed lung cancer that has spread to liver.
I had done chest X- ray done less that 3 weeks before the CT scan and that had shown nothing to suggest cancer. The PET scan also did not show very high activity in nodules and also the size was increased,but not very much from the CT scan that was done 9 months ago. So where did the cancer arise and why we did not see large tumor in lungs and why the liver mass was 3 or 4 times the size of the nodule in lung where the cancer started and lastly why was the chest X- ray unable to give even hint of anything happening.
And that is why my question - How often (doing a CT scan) is enough . The recommendations are to do once a year and that would not and did not catch the cancer early!