Resectability issues with head and neck cancer

Head and neck surgeons often rely on imaging to determine if a neoplasm is resectable. Many of the critical issues are outlined in the American Joint Committee on Cancer Staging Manual, wherein T4a and T4b head and neck cancers are defined as resectable and unresectable, respectively. Even within the T4a advanced resectable classification, there are critical determinants that define whether the surgical option is such that major morbidity and mortality could be expected. This review article examines the imaging literature to determine the accuracy and diagnostic criteria of different modalities for evaluating these critical T4a and T4b factors, which include the following: 1) arterial encasement, 2) prevertebral fascia involvement, 3) mediastinal infiltration, 4) tracheal and esophageal extension, 5) laryngeal cartilage penetration, 6) pre-epiglottic fat involvement, 7) dural spread, 8) bone (mandible/maxilla and skull base) infiltration, 9) perineural spread, 10) orbital involvement, and 11) brachial plexus invasion. For the most part, the studies find MR imaging with higher sensitivity but lower specificity than CT. An ever-increasing role for PET/CT is suggested. Imaging is of great value in the determination of resectability issues listed previously for head and neck cancers, with the possible exception of prevertebral fascia involvement.