[Interest of PET/CT scan fusion to assess mandible involvement in oral cavity and oro pharyngeal carcinomas].
UNLABELLED: The aim of the study is to assess mandible involvement in oral cavity and oropharyngeal carcinomas. OBJECTIVE: To evaluate interest of fusion of Positron Emission Tomography (PET) with Computed Tomography scan (CT scan). METHOD: Eight patients were included in this prospective study. Each patient underwent PET and CT scan of the head and neck before surgery including tumorectomy and mandibulectomy. We compared results of PET- CT fusion with histologic examinations. RESULTS: Oral cavity (6), oropharyngeal (2) carcinoma: Mandibular invasion was suspected by PET-CT in 3 cases, but was confirmed in histological examination in only 2 cases. In 5 cases, PET-CT did not find mandibular invasion; this was confirmed in histological examination in all cases. Sensibility of PET-CT fusion was 100%, specificity was 83%. Positive predictive value was 66% and negative predictive value was 100%. DISCUSSION: PET-CT fusion provided maximal sensitivity. Specificity was better than for MRI but less than CT-scan. There were no false negatives and the false positive rate was 33%. CONCLUSION: PET-CT fusion is interesting to predict mandible involvement. Further studies are necessary to confirm these preliminary results.