What does a PET scan show?

What does a PET scan show?  Most of my masses are very small. Will they show up? Does it show masses in/on bone?

Does anyone know how much they cost?

Any info would be greatly appreciated. Thanks!

[Ken_PA]

Well, it is costly. I believe the cost will be $2,000 and up. Try here:
http://www.remakehealth.com/view_region.asp?cat=1456

Here is what it does: cancer cells usually multiply more rapidly than ordinary cells. Therefore, they take in more glucose sugar for energy than ordinary cells do. For the PET scan, you get injected with a radioactive sugar (called FDG). After a while, the FDG has accumulated in any areas with cancer. Therefore, when you next go to lay down on the table, the scanner will be able to see any areas that 'light up'. It's like getting most of your body scanned at once. It takes a picture.

Yes, it will show small masses if they light up. The PET machine is usually made in combination with a CT scanner, and that can measure the size of anything that the PET detects.

So, the PET doesn't really show masses, it shows areas of increased metabolic activity. That creates a problem: an infection is also an area of increased metabolic activity. The PET cannot reliably tell the difference between infection and cancer. So PET scans are becoming increasingly used to detect hidden infections when there is not even any suspicion of cancer.

Guess what else is an area of increased metabolic activity? Benign hyperplasia (which means the cells are multiplying quickly but it's not cancerous) does, which might be the dysplasia that we talked about before.

So the PET has no guarantee of providing a solid answer.

[bluebird777]

Thanks! Much appreciated

[Ken_PA]

You are very welcome.

I hesitate to tell anybody what to do, but if it were me I'd lean toward getting flow cytometry on the recent biopsy instead.

And about PET: I should mention also that the degree to which any area lights up is given a number, which is called the Standardized Uptake Value (SUV). The higher the vlaue, the higher the metabolic activity in that area. 20 is fairly high. The last I know, though, the SUV isn't a reliable way to distinguish between cancer and infection.

Remind yourself that no cancer has been found so far :)

[bluebird777]

I have been trying to get the flow cytometry test. So far...no luck. But when I meet the oncologist next week...I think it would be a good idea to bring it up.

You are right...I do need to keep reminding myself that none has been found yet. It's just really hard to ignore what I feel inside. Still...I will continue to try to keep the positive look on this.

Thank you again for all of your help! I really appreciate it!

[lilleprechaun]

I appreciated your explanation of the PET scan... it is the first one that has made perfect sense to me.  I had one last Friday and the findings were a hyper-metabolic mass on my lower left lung.  Infection nor cancer hmmm??? I have been sick off and on since last Nov and have had recent shoulder surgery, pretty stressed out lately to say the least.  The pain that brought me back to the Dr  this month is very similar to the pain from back in Nov-March, wheezing (gurgling) and pain when I take deep breaths.    I go in today for an explanation and a course of action to rule out the cancer portion, which I am staying optimistic about, they haven't found anything yet.