Neck dissection: present and future?

A number of issues are at the forefront of current considerations in surgical treatment of the neck in head and neck cancer. These include proposed new definitions of lymph node levels that will lend themselves to clinical and radiographic examination, the possibility of employing molecular studies to supply information on the metastatic potential of the primary tumor in the clinically negative neck, and the results of multi-institutional prospective pathologic studies of neck dissection specimens examining the early distribution of lymph node metastases from various primary sites, to design more effective and efficient surgical procedures for treatment. The pertinent current literature was reviewed, and appropriate data extracted. Various new landmarks have been defined to distinguish the boundaries between sublevels IB and IIA, the lateral borders of level VI, and the boundaries of level VII. These landmarks are more readily distinguishable on physical and radiographic examination than the definitions currently in use. Numerous molecular studies have been employed to detect subclinical metastatic deposits in the neck, but none have been found sufficiently reliable for practical application. Multi-institutional studies have shown that sublevels IIB and level IV are rarely within the first level of lymphatic drainage routes for most primary squamous cell cancers of the head and neck. Therefore, elective selective neck dissections may be further modified to reduce morbidity and operating time. Various new issues in the treatment of cervical metastatic disease are discussed in an effort to improve the accuracy of pretreatment staging, identification of occult disease, and modification of surgical treatment to optimize efficiency and reduce morbidity.