Staging of untreated squamous cell carcinoma of buccal mucosa with 18F-FDG PET:: Comparison with head and neck CT/MRI and histopathology

This prospective, nonrandomized, case-control study evaluated the impact of F-18-FDG PET in staging untreated squamous cell carcinoma of the buccal mucosa (BSCC) and compared the results with CT/MRI and histopathology. Methods: Between January 2002 and April 2004, 102 untreated BSCC patients with cM0 (no evidence of distant metastatic focus on chest radiograph, liver ultrasonograph, and bone scan) were enrolled with either conventional work-up (CWU, n = 51) or PET (CWU+PET, n = 51). All were monitored for at least 6 mo. The comparative diagnostic efficacies of PET and CT/MRI were evaluated using the area under the receiver-operating-characteristic curve (AUC). The primary endpoint was the percentage reduction in futile surgery (preoperative detection of distant metastatic lesions). The secondary endpoint was the 2-y cumulative recurrence rate among study participants (with PET) compared with that of comparable control subjects (without PET). Results: Significant benefits of PET compared with those of CT/MRI for BSCC patients were in the detection of locoregional (AUC, 0.973 vs. 0.928; P = 0.026), regional (AUC, 0.939 vs. 0.837; P = 0.026), and level II (AUC, 0.974 vs. 0.717; P = 0.02) lymph nodes. Two percent (1/51) of the patients experienced a reduction in futile surgery in the CWU+PET group compared with 0% (0/51) in the CWU group. However, no statistical difference was found in the 2-y locoregional control rate between the CWU and the CWU+PET groups. Conclusion: The role of F-18-FDG PET for BSCC with cMO is limited. Although PET is superior to CT/MRI in identifying cervical nodal metastases, it does not improve locoregional recurrence.