Table 1.

Summary of evidence-based suggestions for further evaluation of incidental FDG uptake in the head and neck^a

Site of focal uptake	Evidence/when to further evaluate	Recommended form of evaluation
Pituitary gland	Foci with SUVmax > 4.17	Pituitary MRI and/or hormonal testing
Piriform fossa	Foci with SUVmax ≥ 4.28	Referral to ENT for direct visualization
	Foci with SUVmaxI : SUVmaxC ≥ 1.8
Palatine tonsils	Foci with SUVmax ratio between tonsils > 1.59, 10
Nasopharynx	Foci with SUVmax > 6.011
Oro and nasopharynx not specified above	Inadequate evidence for foci not meeting the above criteria.
Parotid: patients without cancer	Consider referring all foci, as common benign causes usually require further evaluation and some incidental malignancies occur.	Ultrasound, MRI or referral to ENT
Parotid: patients with head and neck malignancy	Focus is much more likely to be either a metastasis from the known cancer or benign.14 Further evaluation may well be unnecessary
Thyroid	All foci	Ultrasound ± FNA

^aLimitations in SUV reproducibility and individual patient characteristics, particularly other life-limiting comorbidities and patient choice, should be taken into account when using this evidence.

ENT, ear, nose and throat; FDG, fluorodeoxyglucose; FNA, fine-needle aspiration; SUV, standardized uptake value.