Produced from a Ge-68/Ga-68 generator (germanium cow, 270-day half-life), allowing on-site PET radiopharmaceutical production without a cyclotron — analogous to how Mo-99 generators supply Tc-99m. Also produced by cyclotron.
Ga-68 DOTATATE PET (Netspot):
- DOTATATE is a somatostatin analogue with high affinity for SSTR2 (somatostatin receptor subtype 2)
- Targets well-differentiated neuroendocrine tumors (midgut NETs, pancreatic NETs, pheochromocytoma, paraganglioma, Merkel cell)
- Replaced In-111 OctreoScan — superior sensitivity (~97% vs ~52%), whole-body PET acquisition in 30 min vs 24–48 hour planar imaging, lower radiation dose
- Essential for patient selection for Lu-177 DOTATATE PRRT therapy (tumor must be DOTATATE-avid)
Ga-68 PSMA-11 PET (Illuccix):
- Targets prostate-specific membrane antigen (PSMA) expressed on prostate cancer cells
- Approved for initial staging of high-risk prostate cancer and detection of biochemical recurrence
- Comparable sensitivity/specificity to F-18 PSMA agents (piflufolastat/Pylarify); shorter half-life means imaging must occur shortly after injection
The 68-minute half-life is well-suited for PET: long enough for synthesis, quality control, and patient injection, short enough for rapid imaging and low patient dose.