ct scan didn't show shrinkage, but dr. says pet scan may?

my husband was experiencing a heavy feeling in his chest this morning so we called the onc and we were told to come in. he had a ct scan done and we were seen by the nurse practitioner. she said, ct scan doesn't show any shrinking of the tumor thus far (brandon has only had two treatments of chemo) but the pleural fluid is gone. my husband was upset at the news that the tumor didn't appear to be shrinking. the nurse said that it still very well could be shrinking but we would need the pet scan to determine this. we are having the pet scan done in approx three weeks (the half way point). she said that the mass may be dying but that it wouldn't show us this on the ct scan only on the pet scan. i feel confused. is this because the pet scan shows living and dead tissue and the ct scan only shows densities and masses? we don't know what to make of this.

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The Pet uptakes in a different manner.Somethings show on both and some on one or the other in the pet.I don't have the copy a friend made me but you can get a 1 page copy from Wickipedia.Non of the Drs or radiologists ever told me that when you have PET scan that they are taking CT pictures at the exact same time as the Positron and from the same angle.That is part of why they can be better than a CT or at least clarify it.I learned that from the Wickipedia article.The PET and the actual pathology report measured my tumor identically I.5xI.8.I am sure thats why the nurse said that.I CT scan measured it as 1.5 and the other said 1.8.My conclusion is the Pet scan measures 3 dimentionally apparently and the Ct doesn't.I think I will ask my pulmonologist if I am right(I usually am LOL) Hope this helps.I still pray for you both,AndiB

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he had two chemo treatments so far, each 21 days apart consisting of taxol, carbo and avastin. i know the only reason the ct scan was initiated was due to symptoms of heavy chest. i just want to know that its "normal" to NOT see much a change yet.

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the oncologist wants to do the pet scan in three weeks. this will be one week before the fourth treatment. a total of six treatments will be done.

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Did they find out what was causing the heaviness in his chest? Take care, JC

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our entire family suffers from seasonal allergies which are bad for all of us right now, so that is what they think the cough is attributed to.

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I say bright side the effusion is gone!!!!!!!!!!! I am sure when he gets his PET Scan it's going to show that the uptake in his mass is greatly reduced due to his tumor dieing off!!!!!!! It takes some time for the body to clear out the necrotic tissue left behind when the tumor dies and that's what must be going on here! Just dead cancer cells showing up on the ct!!!!

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yes, totally awesome that the effusion is gone, the nurse wasn't extremely thrilled, she acted like she knew that was going to happen and it was not a big deal.....whatever.....it was a big deal for us, i def did a happy dance about that.

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This is not uncommon... most Pet scans are done after 4 chemo treatments. The chemo is stil doing its job, killing cancer cells! You're on the right path... No growth, no effusion, and yes...only another pet can give you exact measurements. Chin up! This is good news! Celebrate small victories. Small victory after small victory equals beating this disease... You went to the onc thinking that the cancer has grown because of the chest symptoms...Intead you found out it's allergies, the effusion is gone, the cancer is stable and probably decreasing... Listen an onc won't lie to you, in fact they are brutally honest. Also, your husband's cancer is also being tracked by his bloodwork, cancer cells may be decreasing and it may not be showing on an MRI yet.

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WE just went through this last week with my husband.
He is lllb NSC.
They stopped treatment at 5 weeks to do a CT to see if he was surgical.
They warned us with it being early on in treatment, that we may not see a big change with a CT , but they could not do a PET because more importantly than just showing the size of the Tumor/s, it shows if there is any cancerous activity.
BUT, they cant do a PET for at LEAST 3-4 weeks after your last dose of chemo/radiation.
It highlights areas "Lights Up" areas of Cancerous Activity.
If they dont wait long enough after the last treatment, it will ALL Light up giving a false report.

You can call me if you like...you have my number in a message.

Hope this helps..... God Bless,
Holly

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OH, Our Oncologist told of us a Gentleman whos Tumor was 11 cm.
NO change at all on a CT after full treatment. PET revealed No cancer activity at all, just a large dead mass which was later removed.

HUGS Holly

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oh, hollyjack and milo65,

thank you so much, i feel better. SMALL VICTORIES ARE VICTORIES...ok i am back on track... thank you guys.

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I really would like to add something that I have not seen very much on this board.

For the last 5 scans I have had, (my next one is in Oct.) I have had a PET/CT scan. Prior to them, I just had PET scans.

When I had my first PET/CT scan, I was a little confused. I was given the same radioactive glucose as the PET, but when I saw the machine, it did not quite look like the same machine I had the previous PET scans.

Also, I should mention that the PET/CT scans were done in a different facility. When I asked the person who was going to take the "pictures," she said yes, it was a combination PET and CT and I asked what was the difference. She told me that this machine was much more in depth than a regular PET or a CT scan.

If I am not mistaken, I have seen only 1 other person mention this combination scan. Now I am sorry I have not mentioned it before. Is it possible that many people here do not know about this?

I hope this helps someone.
Love to all,
Marylou

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Marylou- Dr. West recently posted an article re this on cancergrace. Said it is very accurate. Sounds like that will soon become "standard of care"

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my husband had the same thing happen , with very little shrinkage showing on cat scan after a few months of chemo but the pet showed cancer activity way down. i think they measure pet scans by something called an suv level. the pet showed suv level of 27 in january. the next one only a few months later showed suv level of 3 . there are people on this site that has had very little shrinkage but in remission .hope this helps. cindy

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Marylou,

Mine was a PET/CT Scan, the machine is like a newer MRI machine, the only thing I can say about south Florida is that most of the Imaging places seem to have switched to this, I know somewhere I have seen mention of a PET/MRI as something for the future...

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From my understanding of these two ( which I will say is not alot but maybe I can help a little)The ct scan can't see the cancer cells only the mass.The pet scan can tell you how active the cancer is by the SUV levels.My husband is also on carbo, taxol,and avastin. But he doesn't have a tumor.The cancer is just all in the lymphnodes in the lungs and on his back. His first pet scan showed SUV of 11 on the back and 9 in the lungs. After two rounds of chemo the pet scan showed the SUV levels on the back were down to an 8 and the lungs down to a 5.Now I don't really understand all of this but maybe this will help you some.I hope so.
With Love
Maranda

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Hi Tiff,

I know with my dad, his first scan after a few rounds of chemo did not show any shrinkage, but the doctor said the cancer could be dead and the dead cells had not dissipated. Please correct me anyone on here if I am wrong, but I think that the PET scan will light up where the "live" tumors are and just show densities for other things, ie scarring in the lungs, etc. How many rounds of chemo is your husband having? the good news is that it didn't grow and the effusion is gone after two rounds!! That is good, my dad's doctor told us that not growing is definately a positive and a good sign.

Take care,
Jenny

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My husband had a PET/CT scan done yesterday. It said that there was increased areas of glucose uptake in his bones (bad news) and no significant change in the lung/lymph node/pleura and was suggesting that he did not respond to treatment. His oncologist said that the CTs he had during his chemo treatments showed shrinkage. We had to get his pulmonologist to order the PET, his onc wouldn't. Also, his onc told us that he couldn't measure the tumor on the CT scans to tell us how much shrinkage was occurring b/c the fluid (he has minimal fluid remaining from a raging pleural effusion), was hiding the tumor. He was guaging the shrinkage from looking at the lymph nodes. What do you guys think?

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If you can, try to re post this in your own discussion so that more people wll see it and you will have more responses.

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My mom just had a CT/PET scan combined last week. She had her first PET scan at diagnosis time in May 2008. She then had a CT/PET scan combined in March of this year. Her first since May 2008. Then the latest one last week.

PET scan just shows the uptake... It is possible that shrinkage could happen. But the radiologist and the onc are going to have to compare the current PET to the previous one.

Kristi

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