Quantification of lymph nodes in selective neck dissection.

OBJECTIVES: Provide reference for surgeon and pathologist regarding expected yield from selective neck dissections. Quantify lymph nodes obtained from cadaver dissection based on current nodal classification and compare with clinical series. STUDY
DESIGN: 1. Quantification of lymph nodes at levels I-V harvested from human cadavers and correlation with nodal grouping for supraomohyoid (I-III) and lateral (II-IV) neck dissections. 2. Retrospective review of operative specimens from clinical neck dissections for lymph node quantity.
METHODS: 1. Twenty radical neck dissection specimens, harvested from 10 fresh human cadavers without evidence of head and neck cancer, were separated by nodal level for gross and microscopic examination by a pathologist. The quantity of nodes obtained per level for each specimen was tabulated. 2. Charts of patients treated with neck dissection for squamous cell carcinoma were reviewed and tabulated for type of dissection and number of lymph nodes reported.
RESULTS: In the 20 cadaver neck dissections, the average number of lymph nodes removed for levels I-V was 24, with 13 for levels I-III and 19 for levels II-IV. In the clinical review, 98 total neck dissections were included. In the six supraomohyoid dissections, an average of 20 lymph nodes (range, 14-26) were found, with an average of 30 (range, 15-43) in the 11 lateral compartment specimens. In 81 radical or modified radical dissections, an average of 31 nodes (range, 19-63) was reported.
CONCLUSIONS: The number of lymph nodes removed in selective neck dissection should be comparable to that of the corresponding levels in radical neck dissection, provided that strict adherence to surgical boundaries is maintained. Dissection of normal cadavers provides a reference for the surgeon and the pathologist but may under-represent lymph node quantity in the diseased state.