Lessons from Missed Lesions in Head and Neck FDG PET/CT: A Two-Case Report and Brief Review

Head and neck FDG PET/CT interpretation is vulnerable to diagnostic error because of complex anatomy, physiological uptake, post-treatment change, and subtle perineural spread. We report two patients with head and neck squamous cell carcinoma in whom retrospectively visible lesions were not described on earlier FDG PET/CT examinations and were recognized after subsequent progression. The cases illustrate anchoring, premature diagnostic closure, satisfaction of search, and attentional capture near dominant or expected abnormalities. A systematic review of the retroantral fat, pterygopalatine fossa, pterygoid musculature, skull-base foramina, and relevant neural pathways may improve detection. Equivocal skull-base findings may prompt dedicated MRI for further characterization and staging assessment. These illustrative cases do not permit estimation of the frequency of missed lesions or the effect of earlier recognition on treatment outcome.