PET/CT · Oncology

FDG PET/CT — oncology

Staging, restaging and treatment response

¹⁸F-FDG

Preparation

Before the patient arrives and before injection

Fast for at least 4–6 h; plain water is allowed.
Check glucose and record diabetes management.
Avoid strenuous exercise and keep the patient warm and resting.
Review recent therapy, infection and injection-site issues.

Acquisition

Timing, coverage and quality checkpoints

Use a standardised uptake period, commonly around 60 min.
Acquire skull-base-to-thigh or indication-specific coverage.
Use low-dose CT for attenuation/localisation or diagnostic CT when prescribed.
Record uptake time, glucose, activity and scan deviations for comparability.

Activity support

Age and weight are shared across scans

30 y · 70 kg

Administered activity¹⁸F-FDG · body

Minimum140 MBq3.78 mCi

Maximum350 MBq9.46 mCi

2–5 MBq/kg × 70 kg

Weight-based adult range (EANM/SNMMI 2019). On EARL-accredited systems use the EANM 2015 formula: 7 (or 14 when bed overlap ≤30%) MBq·min·bed⁻¹·kg⁻¹ × weight ÷ minutes per bed. Weight-based paediatric range is available. Adult protocols should follow local EARL/DRL optimisation.

Calculation support, not a prescription. Verify the radiopharmaceutical, indication, local DRL, camera technology, product information and an authorised practitioner’s order. Round only under local policy.