Accuracy of (18) F-FDG PET/CT in Detection of Neck Metastases of Oral Squamous Cell Carcinoma in Patients Without Large Palpable Lymph Nodes.

OBJECTIVE: To measure the efficacy of positron emission tomography/computed tomography (PET/CT) in the diagnosis of neck metastases of oral squamous cell carcinoma (OSCC) in patients without enlarged lymph nodes and to determine the threshold of maximum standardized uptake values (SUV(max)) in diagnosis. STUDY DESIGN: In total, 78 OSCC patients without large palpable lymph nodes were included. PET/CT findings were compared with histopathologic neck status. RESULTS: Neck dissection was performed in 78 patients with 98 neck sides, and 31 neck sides harbored metastases. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of PET/CT were 83.9%, 73.1%, 76.5%, 59.1%, and 90.7%, respectively. The area under the curve in receiver operating characteristic analysis was 0.76, which indicated that SUV(max) of lymph nodes was useful in diagnosis of pathologic neck status. The threshold SUV(max) was 2.21, which was the best diagnosis threshold of neck metastasis. CONCLUSIONS: PET/CT is valuable in diagnosis of neck status. The probability of neck metastasis increased with increasing SUV(max) values, but the threshold SUV(max) should not be the sole criterion for determining the presence of neck metastases. Fluorodeoxyglucose PET/CT is recommended for evaluation of neck status in OSCC patients without large palpable lymph nodes.