Fluciclovine F18 PET/CT in Identifying the Origin of Head and Neck Squamous Cell Carcinoma in Patients With Metastatic Cervical Nodal Disease

PRIMARY OBJECTIVES: I. To estimate positive predictive value with a corresponding 95% confidence interval for fluciclovine F18 (18F fluciclovine) positron emission tomography computed tomography (PET CT) to detect a primary site of disease in patients presenting with cervical metastatic nodal disease but a head and neck primary site not apparent on CT of the neck with contrast (contrast enhanced-computed tomography, CE-CT). SECONDARY OBJECTIVES: I. To estimate positive predictive value with a corresponding 95% confidence interval for fludeoxyglucose F-18 (18F FDG) PET CT in the detection of a primary site of disease in patients presenting with cervical metastatic nodal disease but a head and neck primary site not apparent on CT of the neck with contrast. EXPLORATORY OBJECTIVES: I. To compare the lesion to background (L/B) ratios for nodal metastatic disease between 18F fluciclovine PET CT and 18F FDG PET CT. II. To estimate the sensitivity of 18F fluciclovine PET CT and 18F FDG PET CT to detect nodal disease. III. To evaluate for any trends in findings on 18F fluciclovine PET CT and human papillomavirus (HPV) status. OUTLINE: Patients receive fluciclovine F18 intravenously (IV) and undergo PET/CT scan over 20-30 minutes.