Role of 18F-FDG PET/CT in pre and post treatment evaluation in head and neck carcinoma

Figure 13 Hypometabolic necrotic lymph node. A T1N1M0 right glossopharyngeal sulcus squamous cell carcinoma (red arrow) is FDG avid on positron emission tomography/computed tomography (PET/CT) (A). There is a 1.7-cm necrotic right level IIa lymph node seen on contrast-enhanced CT (B). The necrotic lymph node is hypometabolic and may potentially cause a false negative result if the CT portion of the PET/CT or corresponding contrast-enhanced CT were not correlated.