Scan choices: Is there a radiologist in the house?

[Rich66]

So..mom has mets to liver and lung. She had a PET/CT early June which showed mostly inactive liver mets but significant uptake in one of the lung nodules. Been following stubborn lung module with CT late June and early September and it's time for another scan. I have found articles about benefits of tracking chemo efficacy with PET/CT. The doc thinks CT would be more apples to apples with last scan but I know it wouldn't tell much about the liver activity or whether uptake is less in lung nodule. My sense so far is that dedicated CT is better than the non-contrast, low dose cT included in a PET/CT. To complicate things, they want mom to skip contrast in the next CT due to perceived reactions to the contrast.
So...
I'm leaning towards PET/CT giving more overall information than non-contrast traditional chest and ab CTs. But if CT w/o contrast is still measurably superior in terms of tracking the lung nodule absolute size, that might sway things...though that would not say anything about activity in liver or change in uptake which can precede size changes.

One option might be to have insurance pay for the more expensive (eye to thigh) PET/CT and if lung nodule is equivocal, pay for a less expensive chest CT for clarification.
Thoughts?

They are also wanting a mammo..which surprised me given the state of things.

[Lien]

There 's a nuclear medicine tech on the breastcancer list who sometimes answers people's questions about scans and such. She's not a doctor, but she's experienced and a great person with a wonderful sense of humor. Her name is Toya. She may have some suggestions for you.

You can find the list on: www.bclist.org
There are archives you could browse at http://bclist.petebevin.com/
Look for Toya the nuke nut.

Jacqueline

[Joan M]

Rich,

Since there's significant uptake in the lung as shown via PET/CT, I would opt for the same test in following up. Also, since all PET/CTs are C1 to thigh, you'll get information on liver, bones and nodes, too, in terms of lighting up (I've never heard of a PET/CT being less than that).

The safe benchmark for lesions showing up on PET/CT is 1 cm, even though they could possibility light up if a cancerous lesion was under that size.

Joan

[Jackie07]

Rich,

I haven't had a PET since the recurrence was found in 2007. (Forced Onco for one in May 2008. So far nobody has offered to give me another one) There is a trend - according to the new ASCO guideline - discouraging PET use because it does not improve survival rate.
It does sound rediculous, but I think that's probably why her doctor is only prescribing CT.

Sending prayers from Central Texas.

[Rich66]

Got a call back on this.
Turns out it took them a bit to come to the same conclusion: Since she won't be getting contrast with the CT("allergy"), it wouldn't have as much morphological advantage over the PET/CT to outweigh the added uptake information of the latter.

I wonder if the supposed lack of survival advantage applies to those with liver mets, since they (and necrosis) can be diffuse to the point of making CT indeterminate.

[Sherryg683]

I have PET/CT's done every 6 months to make sure everything is OK. That's what I would feel comfortable with if I were you. ..sherryg