US alone has been shown to very sensitive (77.8%-96.8%) and specific (68.75%-97%) in detecting cervical nodal metastases [47,63-65]. In the presence of bulky nodal disease in squamous cell carcinoma, US combined with FDG-PET/CT was found to be a reliable strategy to identify patients with complete nodal response to therapy with a higher combined NPV [65]. Variant 7: Treated cancer of the paranasal sinuses or nasal cavity. Surveillance imaging or follow-up imaging for suspected or known recurrence. Cancer of the paranasal sinuses or nasal cavity is generally treated with a combination of surgery, chemotherapy, and/or radiation therapy [117]. Despite aggressive therapy, recurrence rates may be high, estimated at up to 54% in cases of advanced head and neck squamous cell carcinomas, and these typically occur within the first 2 years following treatment [117]. Early diagnosis of recurrent disease allows for prompt treatment and for providing potential salvage options, which may portend increased survival rates [117]. However, complex posttreatment changes can distort anatomy and may interfere with the detection of subtle findings. Direct visualization with flexible endoscopy is considered the most sensitive method for detecting mucosal recurrence. However, submucosal and deep-seated recurrences are best identified by imaging, preferably cross-sectional imaging such as MRI or functional imaging with FDG-PET/CT. Imaging is also crucial for the detection of distant metastatic disease. Additionally, imaging in the setting of treated sinonasal malignancy may be geared toward detecting complications secondary to therapy, which include but are not limited to cerebrospinal fluid leaks, epistaxis, meningitis, and osteoradionecrosis of the skull base, among others. The appropriate imaging modality to evaluate each potential suspected complication will depend on the clinical scenario and is beyond the scope of this document.
Staging and Post Therapy Assessment of Head and Neck Cancer. US alone has been shown to very sensitive (77.8%-96.8%) and specific (68.75%-97%) in detecting cervical nodal metastases [47,63-65]. In the presence of bulky nodal disease in squamous cell carcinoma, US combined with FDG-PET/CT was found to be a reliable strategy to identify patients with complete nodal response to therapy with a higher combined NPV [65]. Variant 7: Treated cancer of the paranasal sinuses or nasal cavity. Surveillance imaging or follow-up imaging for suspected or known recurrence. Cancer of the paranasal sinuses or nasal cavity is generally treated with a combination of surgery, chemotherapy, and/or radiation therapy [117]. Despite aggressive therapy, recurrence rates may be high, estimated at up to 54% in cases of advanced head and neck squamous cell carcinomas, and these typically occur within the first 2 years following treatment [117]. Early diagnosis of recurrent disease allows for prompt treatment and for providing potential salvage options, which may portend increased survival rates [117]. However, complex posttreatment changes can distort anatomy and may interfere with the detection of subtle findings. Direct visualization with flexible endoscopy is considered the most sensitive method for detecting mucosal recurrence. However, submucosal and deep-seated recurrences are best identified by imaging, preferably cross-sectional imaging such as MRI or functional imaging with FDG-PET/CT. Imaging is also crucial for the detection of distant metastatic disease. Additionally, imaging in the setting of treated sinonasal malignancy may be geared toward detecting complications secondary to therapy, which include but are not limited to cerebrospinal fluid leaks, epistaxis, meningitis, and osteoradionecrosis of the skull base, among others. The appropriate imaging modality to evaluate each potential suspected complication will depend on the clinical scenario and is beyond the scope of this document.