PET (positron emission tomography)
A scan that shows where a radioactive tracer accumulates, so it images what tumours are doing rather than what they look like.
PET detects paired gamma photons from positron annihilation. The tracer determines what is measured: glucose metabolism (FDG), receptor expression (PSMA, SSTR, TROP2, HER2), stroma (FAP), immune cells (CD8), or DNA repair (PARP). Almost always combined with CT or MRI for anatomic reference.
How it works
Positron-emitting isotopes (18F, 68Ga, 89Zr, 64Cu) attached to a targeting molecule; coincidence detection of 511 keV photons; standardised uptake value (SUV) quantifies uptake.
- Whole-body biology in one scan
- Quantitative
- Any target with a ligand can in principle be imaged
- Resolution ~4 mm
- Tracer supply and cost
- Inflammation confounds FDG
Fluciclovine F-18 was the first PET tracer approved for finding recurrent prostate cancer after treatment (2016), and has been largely superseded since 2020 by PSMA PET.
A PET scan that shows which breast cancer deposits still have oestrogen receptors, helping decide whether hormone therapy will work when biopsy is impractical.
Latest papers
topQuery for this technology: (TITLE:"positron emission tomography" OR ABSTRACT:"positron emission tomography") AND (cancer OR tumor OR tumour OR oncology OR carcinoma OR lymphoma OR leukemia OR leukaemia OR myeloma OR sarcoma OR melanoma OR glioma). Results are unfiltered search hits about PET (positron emission tomography), not a curated reading list.