The clinical utility of 18F-FDG PET in evaluating salivary gland malignancies has not been well defined. The largest study by Hong-Lyel was only in 34 patients. He found that the sensitivity of 18F-FDG PET and CT for detecting primary tumors was 31 of 34 (91.2%) and 27 of 34 (79.4%), respectively. In the other 7 patients, CT was unable to detect definitive primary mass lesions in 5 patients, and lesions in 2 patients appeared to be multiple metastases from unknown primary sites. Otehr studies had a similar number of patients with similar results. There are no comparative studies of CT versus PET. It is also not known whether surveillance is at all helpful in these cancers. Two referenced 2012 studies dealt with PET’s ability to stage the neck or distinguish benign form malignant tumors.
Jong-Lyel Roh et al, Clinical Utility of 18F-FDG PET for Patients with Salivary Gland Malignancies J Nucl Med February 2007 vol. 48 no. 2 240-246
Han-Sin Jeong et al, Role of 18F-FDG PET/CT in Management of High-Grade Salivary Gland Malignancies JNM 2007 48:1237-1244
Ja Young Kim et al Diagnostic Value of Neck Node Status Using 18F-FDG PET for Salivary Duct Carcinoma of the Major Salivary Glands JNM 2012 53:881-886
David Hadiprodjo et al, Parotid Gland Tumors: Preliminary Data for the Value of FDG PET/CT Diagnostic Parameters Am. J. Roentgenol. 2012 198:W185-W190
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