文摘
Squamous cell carcinoma of unknown primary of the head and neck (SCCUP) is a heterogeneous disease entity that requires careful examination to locate the occult primary. We examined the diagnostic value of expression of biomarkers, such as human papillomavirus (HPV), p16 and Epstein–Barr virus (EBV), in metastatic lymph nodes vs. <sup>18sup>F-fluorodeoxyglucose (<sup>18sup>F-FDG) positron emission tomography/computed tomography (PET/CT). We prospectively enrolled 54 consecutive SCCUP patients who received HPV, p16 and EBV analyses of lymph node fine-needle aspirates and <sup>18sup>F-FDG PET/CT scans and subsequently underwent examinations and biopsies under general anesthesia to detect primary tumors. The diagnostic performance of the biomarkers and <sup>18sup>F-FDG PET/CT were compared by using receiver operating characteristics (ROC) curve analyses with histopathological results for identification of primary tumors. Primary tumors were identified in 28 (51.9%) of 54 patients: the palatine tonsil in 24, base of the tongue in 1, nasopharynx in 2, and hypopharynx in 1. The sensitivity of p16 (85.7%) and accuracy of HPV (85.2%) were higher than those (42.9% and 68.5%) of <sup>18sup>F-FDG PET/CT (p < 0.05). The area under the ROC curve of HPV was higher than that of <sup>18sup>F-FDG PET/CT (0.857 vs. 0.666, p = 0.007). The disease-free survival rates were higher in the patients with primary tumor detection or p16 nodal immunopositivity than in the other patients (p < 0.05). The results showed that HPV and p16 detection in metastatic lymph nodes can help locate hidden primary tumors, guide definitive treatment and predict patient survival.