Characteristics of Main Markers of Hypoxia for PET
| Hypoxia tracer | First clinical use (year) | Tumor-to-background ratios * | Time after injection (h) | Disadvantages | Tumor types studied |
| 18F-misonidazole | 1992 | 0.88–5.85 | 2–3 | Longer biologic half-life; longer imaging schedule; slow clearance from nonhypoxic tissue; peripheral metabolism | HNC, NSCLC, renal cell carcinoma, soft-tissue sarcoma, breast cancer, brain tumor |
| 18F-FAZA | 2007 | 1.2–3.7; for gliomas, 1.9–15.6 | 2–3 | Longer imaging schedule; peripheral metabolism (?) | HNC, NSCLC, SCLC, lymphoma, gliomas |
| 18F-EF5 | 2008 | 1.15–4.07 | 3 | Longer biologic half-life; longer imaging schedule; slow clearance from nonhypoxic tissue; complex synthesis method | HNC |
| 60/64Cu-ATSM | 2001 (60Cu-ATSM) | 1.0–10.4 | 0.5–1 | Low specificity in some tumor types | HNC, NSCLC, cervical cancer, rectal cancer |
↵* Maximal tumor-to-blood activity or tumor-to-muscle activity or tumor-to-background activity ratios.
HNC = head and neck cancer; NSCLC = non–small cell lung cancer.