Figure 1
From: Detection of primary sites in unknown primary tumors using FDG-PET or FDG-PET/CT
A 54-year-old male with right cervical lymph node metastasis from an unknown primary tumor (patient 9): The patient had radical neck dissection, tonsillectomy, blind biopsy of the nasopharynx and tongue base. The pathology revealed metastatic squamous cell carcinoma in one out of 20 lymph nodes. However, there was no evidence of malignancy in other tissues including tonsiles, tongue base, parotid gland, salivary gland, or nasopharynx; (A) PET/CT showed a hypermetabolic lesion (SUV 13.0) in right cervical lymph node(arrow) at level II; (B) There was no additional FDG uptake suggesting a primary site in the transaxial PET/CT scans of the chest and pelvis.