FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT allows for the detection and localization of primary tumor site and identification of regional nodal disease and distant metastases. The utility of FDG-PET/CT depends on the tumor grade because low-grade salivary gland tumors have relatively low metabolism and may be occult on FDG-PET/CT. FDG-PET/CT is therefore not routinely recommended for initial staging of low-grade salivary gland tumors [108]. FDG-PET/CT has been shown to correctly identify the site of the primary tumor at a similar rate as MRI [114]. FDG-PET/CT alone is not Assessment of Head and Neck Cancer considered sufficient in the initial staging of salivary gland cancer because it does not provide detailed anatomic delineation of the primary site and detection of upstaging features needed. FDG-PET/CT is inferior to MRI for the diagnosis of perineural tumor spread because the small volume of disease and the limited spatial resolution of PET [42,115]. FDG-PET/CT in the initial staging of salivary gland tumors remains a controversial subject [108]. FDG-PET/CT may be superior to conventional cross-sectional imaging in staging of regional neck nodal disease and preoperative planning for neck dissection [114]. One study showed an increased detection rate of regional nodal metastases calculated at 100% with FDG-PET/CT versus 50% with MRI in combination with CXR [114]. Furthermore, FDG- PET/CT may be recommended in the setting of high-grade malignancy because of the increased frequency of distant metastases [108,114]. Other studies have shown that PET/CT provides additional information regarding cervical lymph nodes and distant disease in particular in patients with high-grade carcinomas [114]. The rate of change in treatment plan based on detection of regional and/or distant metastases in patients with salivary gland carcinoma with PET or PET/CT has been calculated at 15% to 47% [114].
Staging and Post Therapy Assessment of Head and Neck Cancer. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT allows for the detection and localization of primary tumor site and identification of regional nodal disease and distant metastases. The utility of FDG-PET/CT depends on the tumor grade because low-grade salivary gland tumors have relatively low metabolism and may be occult on FDG-PET/CT. FDG-PET/CT is therefore not routinely recommended for initial staging of low-grade salivary gland tumors [108]. FDG-PET/CT has been shown to correctly identify the site of the primary tumor at a similar rate as MRI [114]. FDG-PET/CT alone is not Assessment of Head and Neck Cancer considered sufficient in the initial staging of salivary gland cancer because it does not provide detailed anatomic delineation of the primary site and detection of upstaging features needed. FDG-PET/CT is inferior to MRI for the diagnosis of perineural tumor spread because the small volume of disease and the limited spatial resolution of PET [42,115]. FDG-PET/CT in the initial staging of salivary gland tumors remains a controversial subject [108]. FDG-PET/CT may be superior to conventional cross-sectional imaging in staging of regional neck nodal disease and preoperative planning for neck dissection [114]. One study showed an increased detection rate of regional nodal metastases calculated at 100% with FDG-PET/CT versus 50% with MRI in combination with CXR [114]. Furthermore, FDG- PET/CT may be recommended in the setting of high-grade malignancy because of the increased frequency of distant metastases [108,114]. Other studies have shown that PET/CT provides additional information regarding cervical lymph nodes and distant disease in particular in patients with high-grade carcinomas [114]. The rate of change in treatment plan based on detection of regional and/or distant metastases in patients with salivary gland carcinoma with PET or PET/CT has been calculated at 15% to 47% [114].