Role of Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Preoperative Staging of Early Glottic Cancer / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has been widely used to detect regional and distant metastasis or second primary cancers at initial evaluation. The aim of this study was to evaluate the role of combined FDG-PET/CT in detecting early glottic cancers, which has low incidence of regional or distant metastasis. SUBJECTS AND METHOD: We enrolled in our study 551 patients who had previously untreated glottic cancer between 2001 and 2008. Of these, 124 patients with early glottic cancer underwent FDG-PET/CT. Retrospectively, we compared the detection rates of regional, distant metastasis or second primary cancer by FDG-PET/CT with those after neck computed tomography (CT), chest X-ray, and liver sonography. RESULTS: In detecting regional metastasis, the sensitivity and specificity of FDG-PET/CT were 66.67% and 97.25%, respectively, with the positive predictive value (PPV) of 40%, the negative predictive value (NPV) of 99.16%, and the accuracy of 96.77%. The sensitivity, specificity, PPV, NPV and accuracy of neck CT were 66.67%, 96.69%, 33.33%, 99.15%, and 95.96%, respectively. The suspicious distant metastasis (n=1) and second primary cancers (n=7) were observed in FDG-PET/CT. The true second primary cancers occurred at the colon (n=1) and the prostate (n=2). The other cases were proved to be false positive. Distant metastasis and second primary cancers were not detected by the conventional work-up tests. CONCLUSION: The regional metastasis detection rate of FDG-PET/CT was similar to those of the conventional work-up tests. However, compared to the conventional tests, FDG-PET/CT is useful for detecting distant metastasis or second primary cancers in patients with early glottic cancer.