single spot on rib

[lokibear0803]

My recent F-18 scan has reported, among other things, this:

— nonspecific localization near the head of the left 2nd rib. No definite bony metastatic pattern; subtle associated sclerosis on CT, SUV 2.0.

With such a low SUV, I’m thinking this is false positive. Is it not true that single spots on a rib are frequently FP?

FTM I had a bike crash a month ago, with a malicious light pole slamming into my left chest. Don’t ask. So, could this account for the sclerosis and uptake?

TIA for any feedback.

Edit: this was a Pylarify PSMA F-18.

[Tall_Allen]

F18 PET is very sensitive for bone, but it doesn't pick up lymph nodes or visceral organs. Why didn't you get a PSMA PET scan?

The radiologist doubts there is a met on the 2nd rib.

[lokibear0803 in reply to Tall_Allen]

My bad, I misspoke. It was a Pylarify; I was just mindlessly quoting the technician, who mentioned the radioisotope is F-18. I guess other non-PSMA scans (FDG?) also use fluorine-18.

“Mindlessly” b/c my mind basically exploded on reading the rib remark. Thanks for helping me find some remaining fragments.

[Tall_Allen in reply to lokibear0803]

When people say F18 PET scan, they are usually talking about the fluoride (18) PET scan (sodium fluoride is used, but any ionic fluoride (F18) could be used). It is twice as sensitive for bone metastases compared to Pylarify (which also uses F18 as the positron emitter, but the ligand attaches to PSMA on the cancer cell, which is the important part).

SUV max is always compared to background. Radiologists hunt for correlated images - he found scant evidence for you.

[tango65]

Many reading of lesions in ribs with the PSMA PET/CTs may be false positive unless the SUV value of the lesions is high, IMHO higher than 4or 5. If the SUV is 2 I would request a MRI of the rib to confirm it is a met.

[lokibear0803 in reply to tango65]

Thanks tango —

[j-o-h-n]

Next time you hit a light pole you should asked "translate" how to say "excuse me" to the light pole......since they understand Polish...........

Good Luck, Good Health and Good Humor.

j-o-h-n Wednesday 11/22/2023 11:17 PM EST