CTA Neck With IV Contrast There is no relevant literature to support the 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 the paranasal sinuses or nasal cavity. In the case of recurrent disease encroaching on the carotid arteries, CTA of the neck can be used to identify patients at a high risk of bleeding [41]. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT allows for the assessment of treatment response, detection, and localization of recurrence, regional nodal disease, and distant metastases in treated cancer of the paranasal sinuses or nasal cavity. Evaluation of the treated neck is very often complicated by significant treatment-related changes that can be difficult to distinguish from persistent disease after therapy or recurrence. The presence of posttreatment inflammatory change decreases the specificity of findings on FDG-PET/CT [134]. For this reason, imaging with FDG-PET/CT is preferred to occur at a minimum of 12 weeks after completion of therapy to allow for treatment effects to subside [117,118], although imaging as early as 8 weeks after therapy has been suggested [136]. Concurrent infection can similarly give false- positive findings. Because of the relatively low positive predictive values of FDG-PET/CT [150], physical examination as well as complementary imaging with MRI remains of utmost importance to elucidate findings discovered on PET/CT and to determine a degree of suspicion. FDG-PET/CT has a high NPV and therefore is very helpful in excluding recurrence [150]. One study calculated an NPV of 91% of a single PET/CT examination obtained at any time after completion of therapy for head and neck squamous cell carcinoma. NPV would increase to 98% if a second scan was also found to be negative [151]. FDG-PET/CT has been found to accurately diagnose distant metastatic disease in the posttreatment setting.
Staging and Post Therapy Assessment of Head and Neck Cancer. CTA Neck With IV Contrast There is no relevant literature to support the 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 the paranasal sinuses or nasal cavity. In the case of recurrent disease encroaching on the carotid arteries, CTA of the neck can be used to identify patients at a high risk of bleeding [41]. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT allows for the assessment of treatment response, detection, and localization of recurrence, regional nodal disease, and distant metastases in treated cancer of the paranasal sinuses or nasal cavity. Evaluation of the treated neck is very often complicated by significant treatment-related changes that can be difficult to distinguish from persistent disease after therapy or recurrence. The presence of posttreatment inflammatory change decreases the specificity of findings on FDG-PET/CT [134]. For this reason, imaging with FDG-PET/CT is preferred to occur at a minimum of 12 weeks after completion of therapy to allow for treatment effects to subside [117,118], although imaging as early as 8 weeks after therapy has been suggested [136]. Concurrent infection can similarly give false- positive findings. Because of the relatively low positive predictive values of FDG-PET/CT [150], physical examination as well as complementary imaging with MRI remains of utmost importance to elucidate findings discovered on PET/CT and to determine a degree of suspicion. FDG-PET/CT has a high NPV and therefore is very helpful in excluding recurrence [150]. One study calculated an NPV of 91% of a single PET/CT examination obtained at any time after completion of therapy for head and neck squamous cell carcinoma. NPV would increase to 98% if a second scan was also found to be negative [151]. FDG-PET/CT has been found to accurately diagnose distant metastatic disease in the posttreatment setting.