Active discussions

Meet the Other Phone. Flexible and made to last.

Meet the Other Phone.
Flexible and made to last.

Buy now

Please or to access all these features

Talk
Cancer

Find advice & support if you or someone you know has been diagnosed with cancer

Original poster

CAT and PET scans

8 replies

SanctusInDistress · 03/12/2024 19:50

a relative has prostate cancer and the consultant ordered a CAT scan. Weeks later (not started treatment yet) they have now ordered a PET scan to look for metastasis (biopsy result positive). Wouldn’t the CAT scan have shown them
up if there had been any?

OP posts:
olympicsrock · 03/12/2024 19:54

CT scans show physical masses of tumour but might miss small lesions.
a PET scan will show tiny metastases which are biologically active and glow bright but might be missed on CT. PET can also tell if something seen on CT is likely to be a cancer so for example an enlarged lymph node could be benign or malignant.

tothelefttotheleft · 03/12/2024 19:55

olympicsrock · 03/12/2024 19:54

CT scans show physical masses of tumour but might miss small lesions.
a PET scan will show tiny metastases which are biologically active and glow bright but might be missed on CT. PET can also tell if something seen on CT is likely to be a cancer so for example an enlarged lymph node could be benign or malignant.

That's really interesting. I had a ct scan and not a pet one and had wondered why.

Original poster
SanctusInDistress · 03/12/2024 20:45

So basically PET is better to detect metastasis? But then why would they do. CAT scan first why not go straight to a PET scan if they think there might be metastasis?

OP posts:
Topaz89 · 04/12/2024 06:54

I had a CT scan done last week and having a biopsy done next week. If my biopsy comes back saying I have cancer, will I then have a PET scan?

P00hsticks · 04/12/2024 18:29

To another type of scan into the mix, I had an MRI scan after a biopsy came back positive (for womb cancer)

Willowkins · 04/12/2024 18:33

PET scan can also tell the difference between dead and live cancer cells so it will help to detect shrinkage after treatment.

stichguru · 04/12/2024 21:06

So sorry that your relative and you and family are going through this op.
A CAT scan is better at looking at lumps in detail, a PET scan is better at picking up tiny changes in the look of the organs. So when your relative first discovered symptom that made them suspect they had prostate cancer, they will have used a CAT scan to look for tumours and determine whether they were cancerous. A PET scan will then be used to check whether there are little changes in other areas of the body, which might suggest the beginning of other cancerous cells, to small to yet be solid tumour masses, but indicating that some other treatment might be required to irradicate them before they become horrible cancerous tumours that might be uncomfortable and hard to treat.

olympicsrock · 04/12/2024 22:49

stichguru · 04/12/2024 21:06

So sorry that your relative and you and family are going through this op.
A CAT scan is better at looking at lumps in detail, a PET scan is better at picking up tiny changes in the look of the organs. So when your relative first discovered symptom that made them suspect they had prostate cancer, they will have used a CAT scan to look for tumours and determine whether they were cancerous. A PET scan will then be used to check whether there are little changes in other areas of the body, which might suggest the beginning of other cancerous cells, to small to yet be solid tumour masses, but indicating that some other treatment might be required to irradicate them before they become horrible cancerous tumours that might be uncomfortable and hard to treat.

Top explanation. Will borrow in future!
MRIs are particularly good at looking at soft tissues and are excellent at showing the tissue planes of structures in pelvis hence especially good for rectal and ovarian cancers

New posts on this thread. Refresh page