Atypical local laryngeal cancer recurrence mimicking thyroid uptake on 18F-FDG PET/CT

Laryngeal cancer recurrence occurs in 30–50% of patients with T3 and T4 stages of the disease. Post-treatment changes and anatomic alterations may affect the accuracy of anatomical imaging modalities (Agrawal K, et al. Clinical radiology 2015; 70: 536–543). Hybrid 18F-FDG PET/CT imaging was shown to be promising in the assessment of recurrent laryngeal cancers (Plaxton NA, et al. American Journal of Roentgenology 2015; 205: W519–W531). In addition, surgery-induced thyroiditis, transient hyperthyroidism, and postoperative hypothyroidism have been well-reported after total laryngectomy in the literature. Therefore, knowledge of uncommon and atypical patterns of 18F-FDG uptake is crucial for accurate interpretation.