Lymph node pathology. Benign proliferative, lymphoma, and metastatic disease.

The evaluation of cervical lymph nodes is one of the main indications for performing CT and MR imaging of the neck. Imaging may be done for evaluation of an unknown neck mass, but more commonly the neck is imaged to evaluate potential metastasis from a known mucosal malignancy. CT and MR imaging characteristics of both malignant and nonmalignant nodal diseases are reviewed and the differential diagnosis of nodal pathologies for specific imaging findings are discussed. A recently proposed imaging-based nodal classification for metastatic nodal diseases from head and neck cancer is also described.