Has anyone heard of a petscan numberin... - Lung Cancer Support

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Has anyone heard of a petscan numbering system?


I've been in remission 3 years ... NSCLC squamous. Had a new petscan. Oncologist explained that a contrast is injected. Any cancer will light up. He said a 3 is normal no cancer. My number is 8. Has anyone heard of this number system? I forgot to ask what the highest number is. For the last 2.5 yesrs I have been told the spot is inflammatoon from previous radiation. Anyway, I will have to go for biopsy.

4 Replies

Get a second opinion and research on line who specializes and is the best. 🙏🙏💕

I have had 2 PET scans in the last 5 years, no one ever mentioned a number system. I was only told that if its cancer, it will light up. If I understand correctly, they inject a kind of radioactive sugar solution. Cancer feeds on sugar, so if the nodule/tumor is cancer, the sugar solution will be drawn to it causing it to light up in the pictures. My oncologist as well as my thoracic surgeon both said if it lights up, most likely it's cancer and a biopsy is needed. If its not cancer, it will not light up.

This number system could be something new, something not widely known yet, but I agree with Cynric01, get a second opinion, quickly.

I had stage 2 squamous cell lung cancer 5 years ago and they had to remove the upper left lobe. Two months ago I lost the upper right to stage 1A squamous cell lung cancer.

They found a nodule on my right lung last January (2017) that was 2 mm in size, in December 2017 a CT scan showed the nodule had grown to 7 mm, too small to do anything with, but the fact that is was growing was cause for concern and I was scheduled for a new CT scan in March, at that point it was 11 mm (or a bit over 1 cm).

If your spot is not growing, chances are its not cancer.

Please keep in touch, let me know how you are doing.

Kathy53 in reply to KatherineK

Thank you for information.

Hi Kathy,

The injection they give before a PET/CT is called F-fluorodeoxyglucose or FDG. I like to refer to it as radioactive glucose. Cancer cells are more active and require more sugar (glucose) than non cancerous cells. This activity shows up as ‘brightness ‘ on a PET. The results are measured in SUV (standardized uptake values) units and is a measure of how bright the area appears on the scan. I’ve heard SUV above 2.5-3 is suggestive of metastatic lesion but these numbers can be skewed if inflammation or infection is present.

If you have had previous PET scans, the radiologist compares the findings and watches for climbing or declining SUV in a suspicious area. It would be interesting to know if this was the first time a high SUV was measured or if it has been climbing over time. You can ask for any and all test results for your files if you want to have them. I get PET/CT every 3-4 months and tumor marker blood levels every 3 weeks to keep an eye out for any potential progression. Three years in remission is a great accomplishment and the new biopsy just might show no cancer. Good idea to get it done, nonetheless. Best wishes.

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