Prognostic value of FDG PET/CT in head and neck squamous cell carcinomas

The purpose of this study was to evaluate the use of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) to identify the presence of cervical lymph nodes metastases and extracapsular spread with histologic correlations in head and neck squamous cell carcinoma.

The medical records of 54 patients who underwent (18)F-FDG PET/CT for head and neck squamous cell carcinoma before surgery were reviewed. Receiver operating characteristic (ROC) analysis was performed to differentiate patients with cervical lymph node metastasis from those without lymph node metastasis. The same statistical analysis was done to differentiate cervical lymph nodes with extracapsular spread from those without extracapsular spread.

Metastatic disease was diagnosed histologically in 49% (26 of 54) of the patients. Extracapsular spread was present in ten of the 54 patients (19%). When ROC curve analysis and maximum standardized uptake (SUVmax) values were used to detect cervical lymph node metastasis, the area under the ROC curve was 0.96 and the optimal cutoff value for SUVmax was 4.05 based on ROC curve analysis. The sensitivity and specificity of SUVmax for the detection of cervical lymph node metastasis using this cutoff point were 92% and 88%, respectively. When ROC curve analysis and SUVmax values were used in order to detect extracapsular spread, the area under the ROC curve was 0.86, and the optimal cutoff value for SUVmax was 4.15 based on ROC curve analysis. Using this cutoff value, the sensitivity and specificity of SUVmax for the detection of extracapsular spread were 83% and 88%, respectively.

In our study, a median (18)F-FDG PET/CT SUVmax cutoff value of 4.15 was found to be related with cervical lymph node metastasis and extracapsular spread in patients with head and neck cancer.