Comparison of positron emission tomography and computed tomography for the detection of cervical lymph node metastases of oral squamous cell carcinoma

Objective: To investigate the use of positron emission tomography for the detection of cervical metastases of oral squamous cell carcinoma. Patients and Methods: Twenty four patients with histologically confirmed oral squamous cell carcinoma, without previous surgery, radiation therapy, or chemotherapy, and with pretreatment computed tomography and positron emission tomography scans, were included. In this retrospective chart review, data were collected for computed tomography and positron emission tomography findings, treatment, and outcomes. The findings for computed tomography, positron emission tomography, and histopathology were analysed by paired Fisher's exact t test. Results: A statistically significant correlation was noted between computed tomography and positron emission tomography findings (p = 0.033) as judged by the histopathology results of 8 neck dissections. No correlation was found between computed tomography findings or positron emission tomography and histopathology. Among the 14 patients with positive computed tomography and positron emission tomography scans, 9 were ultimately documented to have cervical metastases. Among the 6patients with negative computed tomography and positive positron emission tomography, 5 had neck lymph node metastases (p = 0.048) during follow-up, while patients with negative positron emission tomography did not show neck metastases. Conclusions: In comparison with conventional computed tomography, positron emission tomography provided additional information for the detection of cervical lymph node metastases of oral squamous cell carcinoma. The importance of positron emission tomography for the early detection of neck lymph node metastases is emphasised.