Comment by throwup238

PET scans are not really unreliable, they’re just very sensitive and lots of anomalies ranging from benign cysts to malignant tumors show up on them. It’s not always possible to differentiate them without other measures like biopsies, so that’s where the false positives come in.

Getting regular scans to track cancer progression is a different matter altogether, since most of the blips can be eliminated over time and there’s a history to compare against.