Question about difference between PET and other scans

kari88

Hi, i got diagnosed at 17 with NPC 5 years ago, then again with mets in bones,liver,lung and spleen almost 4 years ago. I did 10 cycles of carboplatin, gemcitabine and taxol + radio therapy and i was clear until may this year when the doctors spotted a recurrance in the spleen, everything else was clear. I had a spleenectomy, and 4 more cycles of gem/carbo this summer.

I live in Iceland and we only have MRI,CT and bone scans and i just had mine yesterday and I am so glad to say those where clear, I so want to become a daddy someday, i will try and keep fighting to make that come true

I read on here, this excellent site that most of you have regular PET scans, and my doctor wants to send me to Denmark for a PET scan. My question is, why is PET scan different, i hear a lot about false positive ones, is it worth is after having an MRI, CT and a bone scan? Why is PET scan so widely used?

Good luck to you all fighting just like me, this forum is great and there are a lot of good people on here

ratface

what little I've gleaned
Is that they all have value and are good at finding different types of cancer in different places in the body. Generally speaking the CT gets more detail, the MRI gets the big mass picture and the PET tells you about cell activity presumed to be cancer above certain values. Together they paint a picture for the doctors who all seem to have their favorite scanning method perhaps based on cancer type and tissue location. The test itself is rather painless and uneventful but rather expensive in comparison to the others. Congrats on your recent scans.

jim and i

not sure
I am not sure what the difference is but the PET seems to be the ultimate in scans. I have seen both Ct and PET on my mother's lungs and the PET showed more detail in my opinion.

Congrats on the clear scans. Praying that PET (if you decide on) is clear as well.

Debbie

robinleigh

congrats
on your clean scan report. I'm really not sure about the difference in scans but I have been told that sometimes insurance will cover a ct scan more often than a pet scan. If you don't get a satisfactory answer on this incredible site, you can try the oral cancer foundation. They are quite knowledgable as well!

My husband has mets to his pelvis and femur and I never seem to find many others with that recurrence. It is encouraging to hear that you have battled it and won a second time. If you don't mind my asking...what is radio therapy? Is it for treatment or pain management?

Best wishes to you in finding scan answer and in your continued good health. You will make a wonderful father!

Robinleigh

mixleader

ratface said:

what little I've gleaned
Is that they all have value and are good at finding different types of cancer in different places in the body. Generally speaking the CT gets more detail, the MRI gets the big mass picture and the PET tells you about cell activity presumed to be cancer above certain values. Together they paint a picture for the doctors who all seem to have their favorite scanning method perhaps based on cancer type and tissue location. The test itself is rather painless and uneventful but rather expensive in comparison to the others. Congrats on your recent scans.

Scans
Yes, that is pretty much the way it was explained to me also. I have one doc who prefers PET/CT and another doc that likes MRI. He said the MRI had greater detail but cannot determine what a mass is. A PET/CT will glow when it 'sees' cancerous activity. I think I have had all of these scans and some of them multiple times.

Roger

Pam M

Good Scans - Good News
Congrats on your recent scans - hope the PET (if you have it) is the next good scan you have.

My doctor prefers the CT/PET combination - where I go, it's two different procedures - the CT uses a "contrast agent" that's injected in, and the scan shows masses, or "things" or absence of tissue or growths. The PET uses radioactive "sugar" that is also injected, and the scan monitors which parts of the body show activity, and the levels of activity. I was told that cancer cells will show more activity than normal cells - so even if you can't actually see any masses, PET will (theoretically) be able to spot cancer before a CT can. Here in the US, PET scans are much more expensive than MRIs and CTs, so many insurance companies will not approve the PET.

kari88

Pam M said:

Good Scans - Good News
Congrats on your recent scans - hope the PET (if you have it) is the next good scan you have.

My doctor prefers the CT/PET combination - where I go, it's two different procedures - the CT uses a "contrast agent" that's injected in, and the scan shows masses, or "things" or absence of tissue or growths. The PET uses radioactive "sugar" that is also injected, and the scan monitors which parts of the body show activity, and the levels of activity. I was told that cancer cells will show more activity than normal cells - so even if you can't actually see any masses, PET will (theoretically) be able to spot cancer before a CT can. Here in the US, PET scans are much more expensive than MRIs and CTs, so many insurance companies will not approve the PET.

Thank you
For your wonderful replys, im going to see the doctor today and we will decide on the PET scan, I think i will go and have it, even though it makes me scared

To Robin, im sorry i meant to write radiation therapy, english is not my first language, im a bit rusty. I hope your husband gets well, what treatment is he undergoing?

Hondo

Hi Kari
Glad to hear your scans are all clean and you are doing well. I too had NPC and mine came back three times and like you I fought it with everything I had, it is in remission right now all this was 6 years ago and I am doing well.

I just finished my PET scan last week and the different between the PET and MRI or CT is that the PET looks at the hold body. Yes there are sometimes that is gives a false positives but it like the MRI’s and CT they are read by people and sometimes mistakes are made in the reading. Like I said a PET looks at the complete Body for Cancer, an MRI or CT looks at just one area of the body.

Hope this helps and praying for you to be a daddy someday my friend.
Hondo

Skiffin16

PET
Just to clear up a few statements from above....as I understand it.

The PET doesn't actually show cancerous activity, it show detail on areas or cells with high activity. These don't necessarily mean they are cancerous cells.

Biopsy and tissue examination and testing confirm the cancer.

Which also relates to the false positives you referred to. False positives are those areas that light up, but aren't cancerous.

They can be anything from infections, residual activity left over from radiation treatment, or other things causing the high activity.

Plus the PET is about 4-5X the cost of the CT...

My CT's are in the range of around $1,500-$2,000, PET is closer to $8,000 - $10,000.

Best,
John

Kent Cass

Skiffin16 said:

PET
Just to clear up a few statements from above....as I understand it.

The PET doesn't actually show cancerous activity, it show detail on areas or cells with high activity. These don't necessarily mean they are cancerous cells.

Biopsy and tissue examination and testing confirm the cancer.

Which also relates to the false positives you referred to. False positives are those areas that light up, but aren't cancerous.

They can be anything from infections, residual activity left over from radiation treatment, or other things causing the high activity.

Plus the PET is about 4-5X the cost of the CT...

My CT's are in the range of around $1,500-$2,000, PET is closer to $8,000 - $10,000.

Best,
John

Cost
Might be the difference between Florida and a smallish midwestern community, but I have seen my PET Scan/Ct bill, and is typically in the $4,500 range. Possible my # is after the "insurance adjustment," but I don't think so.

Pet Scans take about 1.5-hours to get done, in total, I might add. Scan, itself, takes around 45-minutes. The CT takes about 5-minutes, and for it to cost over $1K- hmmm. Figure a lot of the cost is with the Drs who interpret the tests, as they do make the big money.

kcass

Hondo

Kent Cass said:

Cost
Might be the difference between Florida and a smallish midwestern community, but I have seen my PET Scan/Ct bill, and is typically in the $4,500 range. Possible my # is after the "insurance adjustment," but I don't think so.

Pet Scans take about 1.5-hours to get done, in total, I might add. Scan, itself, takes around 45-minutes. The CT takes about 5-minutes, and for it to cost over $1K- hmmm. Figure a lot of the cost is with the Drs who interpret the tests, as they do make the big money.

kcass

Hi Kent
I just did a PET at MD Anderson and it took 1 hour for the shot and then 30 minutes in the machine to complete the hold thing. The cost for my last PET was $5,500 and the MRI was $4,500, so walk out with a $10,000.00 bill to pay when finish.

Hondo

Skiffin16

Kent Cass said:

Cost
Might be the difference between Florida and a smallish midwestern community, but I have seen my PET Scan/Ct bill, and is typically in the $4,500 range. Possible my # is after the "insurance adjustment," but I don't think so.

Pet Scans take about 1.5-hours to get done, in total, I might add. Scan, itself, takes around 45-minutes. The CT takes about 5-minutes, and for it to cost over $1K- hmmm. Figure a lot of the cost is with the Drs who interpret the tests, as they do make the big money.

kcass

New Machine
Kent,

The last I had about a month or so ago was their new machine....

It looked like two of the old machines butted together, two big tubes.

Anyways, everything was cut by about 30% (other than cost, LOL)....

The contrast drink took about 30 minutes and a reduced amount. Same with the time in the machine, down from around 30 minutes to 20 minutes...

Cost of the machine alone was $8032.00, my cost was $650.00.

JG

timreichhart

Skiffin16 said:

New Machine
Kent,

The last I had about a month or so ago was their new machine....

It looked like two of the old machines butted together, two big tubes.

Anyways, everything was cut by about 30% (other than cost, LOL)....

The contrast drink took about 30 minutes and a reduced amount. Same with the time in the machine, down from around 30 minutes to 20 minutes...

Cost of the machine alone was $8032.00, my cost was $650.00.

JG

I was told by my doctor PET scan shows more then CT/MRI
I was told by my chemo/radiation doctor that PET scans shows more then CT/MRI ever can due the clear picture of PET scan because they tell me everytime I get a PET scan I cant move or it will mess up the PET scan and now with CT/MRI you can move a bit and not mess it up.

Which I am going to get my year post PET scan done in about 4weeks from now but the 28th of this month I am getting CT scan of my chest/lungs to see there is anything wrong when I get my Bronchoscopy done by my lung doctor. Yes I am getting CT scan and Bronchoscopy done on the same day.

Also for my cost of CT scan was about 1200 dollars and my MRI was about 1500 dollars and my first ever PET scan was about 5000 and my post PET scan after I was done with cancer treatments was done first 6 months it cost about $3150.

So my next month PET scan will cost me about $3150.

rozaroo

timreichhart said:

I was told by my doctor PET scan shows more then CT/MRI
I was told by my chemo/radiation doctor that PET scans shows more then CT/MRI ever can due the clear picture of PET scan because they tell me everytime I get a PET scan I cant move or it will mess up the PET scan and now with CT/MRI you can move a bit and not mess it up.

Which I am going to get my year post PET scan done in about 4weeks from now but the 28th of this month I am getting CT scan of my chest/lungs to see there is anything wrong when I get my Bronchoscopy done by my lung doctor. Yes I am getting CT scan and Bronchoscopy done on the same day.

Also for my cost of CT scan was about 1200 dollars and my MRI was about 1500 dollars and my first ever PET scan was about 5000 and my post PET scan after I was done with cancer treatments was done first 6 months it cost about $3150.

So my next month PET scan will cost me about $3150.

Pet Scan
Had the combined pet/ct scan done in Montreal Quebec. The total cost was $2,400. Pet scan's are not offered to head & neck patient's here in Ontario. If you need one you must pay your own. Canada is made up of provinces & each province has separate health care.

robinleigh

kari88 said:

Thank you
For your wonderful replys, im going to see the doctor today and we will decide on the PET scan, I think i will go and have it, even though it makes me scared

To Robin, im sorry i meant to write radiation therapy, english is not my first language, im a bit rusty. I hope your husband gets well, what treatment is he undergoing?

Wow
You got some great explanations on differences in scans this site is fantastic! Good luck with your decision. It is scary to have the pet scan but I thinking knowing for sure what you are dealing with is better than the state of uncertainty. Hopefully, your pet will be clear! Do you have a friend to accompany you?

They have not recommended radiation for my husband. He is on chemo protocol of carboplatin, erbitux, and 5FU. Pet scan in a couple of weeks to see if there's any response and believe me, I will be terrified!

kari88

robinleigh said:

Wow
You got some great explanations on differences in scans this site is fantastic! Good luck with your decision. It is scary to have the pet scan but I thinking knowing for sure what you are dealing with is better than the state of uncertainty. Hopefully, your pet will be clear! Do you have a friend to accompany you?

They have not recommended radiation for my husband. He is on chemo protocol of carboplatin, erbitux, and 5FU. Pet scan in a couple of weeks to see if there's any response and believe me, I will be terrified!

Thank you all for your
Thank you all for your replys, i will go to denmark in 3-4 weeks and have the pet scan, now im just crossing my fingers for a clean one!

Im shocked to hear how much many of you have to pay for the scans, and that is a lot of money. I pay around 30-50 dollars for my scans. Around 20-30 to see the doctor and most of my medication is free. But then again, the service and the machines might not be as good.

Robin, I hope your husband gets a good scan and you have many years left together, I find it strange that the doctors are not going to give him radiation therapy, since npc is supposed to be sensitive to it. Good luck to everyone, i will pray for you

ac

My understanding
Hi,

My understanding of the scans are as follows:

CT: This is an X-Ray with contrast to enhance the images.

PET: This is a measurement (standardized uptake value, SUV) of the metabolic activity of cells. Cancer cells have a higher metabolic rate than normal cells. The test involves an injection of a radioactive isotope with a short half life in a glucose solution. As the cancer cells assimilate the glucose more than the normal cells, they will be lighted up by the radioactive isotope. That said, inflammed cells do use more glucose than normal cells so they too may light up albeit may not be as bright as a cancer cell. Hence, the PET scan really has to be used in conjection with a CT/MRI.

MRI: Don't know too much other than it could be more accurate than a CT?