Preliminary multi-institutional prospective pathologic and molecular studies support preservation of sublevel IIB and level IV for laryngeal squamous carcinoma with clinically negative neck

Abstract

Level II-IV selective neck dissection, often performed bilaterally, has become the procedure of choice for elective dissection of the clinically negative (N0) neck in the treatment of laryngeal cancer. The most significant morbidity of this procedure is dysfunction of the accessory nerve, incurred by the necessity of mobilization and retraction of the nerve in order to remove the contents of sublevel IIB. Other morbidity includes possible injury to the phrenic nerve and chylous fistula. These complications are associated with the dissection of level IV. A number of prospective multi-institutional studies of the distribution of cervical lymph node metastases in the neck indicate that lymph nodes in sublevel IIB and level IV are rarely involved in cases of laryngeal cancer with N0 neck. Information was obtained by the study of neck dissection specimens by conventional light microscopy, and by molecular analysis of the specimens. Molecular analysis reveals a significant number of metastases that are not discovered by light microscopy, and is thus essential for this type of evaluation. The authors conclude that these preliminary studies indicate that it is safe and appropriate to eliminate dissection of sublevel IIB and level IV from the elective neck dissection performed for laryngeal cancer with N0 neck. This practice will reduce both operating time and morbidity, particularly accessory nerve dysfunction, without compromising the oncologic result. Further prospective studies are needed to confirm these conclusions.