The use of IV contrast may improve detection of mediastinal and hilar adenopathy, distinguishing nodes from mediastinal vessels and aid in delineation of soft tissue extension of skeletal metastatic disease. There is a paucity of relevant supportive literature specifically comparing the diagnostic performance of CT chest with IV contrast and CT chest without IV contrast. CT Chest Without and With IV Contrast There is no relevant literature to support the use of CT chest without and with IV contrast in the evaluation of suspected or diagnosed NPC or EBV-associated unknown primary of the head and neck. Assessment of Head and Neck Cancer CT Chest Without IV Contrast CT chest without IV contrast can accurately identify pulmonary metastasis and be used to detect thoracic nodal and skeletal metastases to the ribs or vertebrae. NPC has a relatively high rate of distant metastases with the lung being the second most common site of distant disease after osseous metastases. Although FDG-PET/CT is preferred for the staging of advanced stage NPC because it allows for simultaneous detection of metastatic disease outside the thorax, CT chest may be considered for screening of pulmonary metastatic disease. CT chest confers a superior spatial localization and contrast resolution compared to radiography, allowing for the detection of small pulmonary nodules [15]. CT chest may also be useful in patients with NPC associated with smoking and alcohol intake, increasing the risk for synchronous lung cancer. The use of IV contrast may improve detection of mediastinal and hilar adenopathy, distinguishing nodes from mediastinal vessels and aiding in delineation of soft tissue extension of skeletal metastatic disease. Noncontrast CT chest may be considered as an alternative and is part of routine clinical practice, although there is paucity of relevant supportive literature evaluating the use of CT chest without IV contrast.
Staging and Post Therapy Assessment of Head and Neck Cancer. The use of IV contrast may improve detection of mediastinal and hilar adenopathy, distinguishing nodes from mediastinal vessels and aid in delineation of soft tissue extension of skeletal metastatic disease. There is a paucity of relevant supportive literature specifically comparing the diagnostic performance of CT chest with IV contrast and CT chest without IV contrast. CT Chest Without and With IV Contrast There is no relevant literature to support the use of CT chest without and with IV contrast in the evaluation of suspected or diagnosed NPC or EBV-associated unknown primary of the head and neck. Assessment of Head and Neck Cancer CT Chest Without IV Contrast CT chest without IV contrast can accurately identify pulmonary metastasis and be used to detect thoracic nodal and skeletal metastases to the ribs or vertebrae. NPC has a relatively high rate of distant metastases with the lung being the second most common site of distant disease after osseous metastases. Although FDG-PET/CT is preferred for the staging of advanced stage NPC because it allows for simultaneous detection of metastatic disease outside the thorax, CT chest may be considered for screening of pulmonary metastatic disease. CT chest confers a superior spatial localization and contrast resolution compared to radiography, allowing for the detection of small pulmonary nodules [15]. CT chest may also be useful in patients with NPC associated with smoking and alcohol intake, increasing the risk for synchronous lung cancer. The use of IV contrast may improve detection of mediastinal and hilar adenopathy, distinguishing nodes from mediastinal vessels and aiding in delineation of soft tissue extension of skeletal metastatic disease. Noncontrast CT chest may be considered as an alternative and is part of routine clinical practice, although there is paucity of relevant supportive literature evaluating the use of CT chest without IV contrast.