Generally, CT is reserved for the evaluation of treatment complications or when there are indeterminate findings regarding osseous invasion [107,108]. CT may prove to be especially useful in the setting of suspected bone involvement because of its improved detection of cortical erosion [112]. The use of IV contrast is recommended to better outline the extent of the primary site. CT Neck Without and With IV Contrast There is no relevant literature to support the routine use of CT neck without and with IV contrast in the follow-up imaging or evaluation of known or suspected recurrence of treated cancer of a major salivary gland. CT Neck Without IV Contrast There is no relevant literature to support the routine use of CT neck without IV contrast in the follow-up imaging or evaluation of known or suspected recurrence of treated cancer of a major salivary gland. Contrast enhancement is imperative in order to correctly identify and delineate recurrence, distinguishing it from treatment changes. CTA Neck With IV Contrast There is no relevant literature to support the routine use of CTA of the neck with IV contrast in the follow-up imaging or evaluation of known or suspected recurrence of treated cancer of a major salivary gland. In the case of recurrent disease encroaching on the carotid arteries, CTA of the neck can be used to identify patients at high risk of bleeding [41]. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT allows for the assessment of treatment response and detection and localization of recurrence, regional nodal disease, and distant metastases. The utility of FDG-PET/CT depends on the tumor grade, because low-grade salivary gland tumors tend to have relatively low metabolism and may be occult on FDG-PET/imaging. FDG- PET/CT is therefore not routinely recommended for follow-up of low-grade salivary gland tumors [108]. The presence of posttreatment inflammatory change decreases the specificity of findings on FDG-PET/CT.
Staging and Post Therapy Assessment of Head and Neck Cancer. Generally, CT is reserved for the evaluation of treatment complications or when there are indeterminate findings regarding osseous invasion [107,108]. CT may prove to be especially useful in the setting of suspected bone involvement because of its improved detection of cortical erosion [112]. The use of IV contrast is recommended to better outline the extent of the primary site. CT Neck Without and With IV Contrast There is no relevant literature to support the routine use of CT neck without and with IV contrast in the follow-up imaging or evaluation of known or suspected recurrence of treated cancer of a major salivary gland. CT Neck Without IV Contrast There is no relevant literature to support the routine use of CT neck without IV contrast in the follow-up imaging or evaluation of known or suspected recurrence of treated cancer of a major salivary gland. Contrast enhancement is imperative in order to correctly identify and delineate recurrence, distinguishing it from treatment changes. CTA Neck With IV Contrast There is no relevant literature to support the routine use of CTA of the neck with IV contrast in the follow-up imaging or evaluation of known or suspected recurrence of treated cancer of a major salivary gland. In the case of recurrent disease encroaching on the carotid arteries, CTA of the neck can be used to identify patients at high risk of bleeding [41]. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT allows for the assessment of treatment response and detection and localization of recurrence, regional nodal disease, and distant metastases. The utility of FDG-PET/CT depends on the tumor grade, because low-grade salivary gland tumors tend to have relatively low metabolism and may be occult on FDG-PET/imaging. FDG- PET/CT is therefore not routinely recommended for follow-up of low-grade salivary gland tumors [108]. The presence of posttreatment inflammatory change decreases the specificity of findings on FDG-PET/CT.