When is the PET Scan done?

Sign off
For what it's worth, my experience is similar to Mike's (Landranger's). I had CT scans every three months followed immediately by visits with OncoMan to evaluate results. At the six month points, both CT and PET were ordered, again followed by visits with OncoMan.

As I understand it from what I've experienced and from what I've read, and I speak only as a fellow survivor, a CT scan is used to capture the anatomy at a given point in time, and, if no obvious anomalies are detected, used after the NEXT scan for comparison: the two are compared to see that nothing has changed.

If there have been changes, significant changes, there is perhaps cause for some concern and maybe even alarm.

A PET scan captures your metabolism (also at a given moment, to be sure) and evaluates it for what I have always heard referenced as 'hot spots'. It is my understanding that the dye you are injected with prior to the scan is used to 'pump up the volume' with respect to cells that are over-amped for sugar intake (this does not mean, as some misconstrue, that sugar is bad for you). The PET scan highlights those areas that are really sucking down the treats, and these become the so-called hot spots.

Your doctor, Jim, can clearly explain that better.

Both pose potential hazards to your health, of course, as both rely on radiation to get the job done, the PET scan, typically, for longer than the CT scan.

That is a good trade-off for us, because it is good, as you note, to know what is going on. But it also deters your doctors from ordering them on a weekly or monthly basis. They want to look out for you, hopefully, and part of that is evident in their efforts not to give you such scans before their time.

To make this simple, in my experience the CT scan discovers the anomalies (if there are any) and the PET scan determines whether these anomalies are 'hot'.

Just for the record, a CT scan may note new anomalies that are simply scar tissue. More likely, a PET scan will discover hot spots that are really not cancer but infectious areas (a decaying tooth for example or cellulitis to name but two), or some such.

A good doctor, I think, will not rely on one scan of either type, or even the combination of the two taken at one time, to determine what is going on, but will then wait, and take those pictures again to see if they look the same or if, in fact, the anomalies have grown.

In any event, Jim, do not think of the PET scan as the 'big sign-off'. The big sign-off, and there has been some discussion in this board about WHEN, but the big sign-off is when your docs declare you all clear and tell you that you are among the fortunate who have survived it.

The 'big sign-off' is when YOU feel that you are all clear.

As usual, I ramble on.

Best wishes with your scan(s) and with your results.

Take care,

Joe