Identification of distant metastases with PET-CT in patients with suspected recurrent head and neck cancer

OBJECTIVES

To investigate the utility of positron-emission tomography/computed tomography (PET-CT) in identifying distant metastatic disease in patients with suspected recurrent head and neck squamous cell cancer (HNSCC).

STUDY DESIGN

Retrospective analysis.

METHODS

Retrospective analysis of 64 consecutive patients with suspected recurrent HNSCC following definitive treatment who underwent PET-CT imaging were eligible for inclusion. Patients with previous known distant metastatic disease were excluded.

RESULTS

The majority of patients (81%) had TNM stage III or IV disease. PET-CT was suspicious for pulmonary malignancy in 14 patients (22%) and indeterminate in 6 patients (9%). Pulmonary metastases or a new lung primary were present in 10 patients (16%): 7 of 14 patients with positive PET-CT scans (50%) and 3 of 50 patients with negative or indeterminate PET-CT scans (6%). Including nonpulmonary sites, the overall incidence of distant disease was 23% (15/64) with 20% (13/64) unsuspected prior to PET-CT. The sensitivity and specificity of PET-CT in predicting distant malignancy was 86% and 84%, respectively, with a positive predictive value of 60% and a negative predictive value of 95%. There was a significant correlation between standardized uptake value (SUV) on PET-CT and positive histology, with a mean SUV of 8.5 (range, 4.7-16.2) in patients with distant metastases compared with a mean SUV of 2.9 (range, 1.9-4.2) in patients with benign pathology (r = 0.87, P < .0001).

CONCLUSIONS

A significant number of patients with recurrent HNSCC have distant metastases at the time of recurrence. These data suggest that PET-CT improves detection of metastatic disease in the high-risk patient and should be performed as part of the routine evaluation of patients with suspected recurrence prior to salvage surgery.