Preoperative Radiotherapy Decreases Lymph Node Yield of Neck Dissections for Head and Neck Cancer

Objective. Determine if preoperative radiation therapy (RT) decreases the lymph node (LN) yield found at the time of neck dissection. Study Design. Cross-sectional analysis of Surveillance, Epidemiology, and End Results (SEER) database. Methods. The SEER database was queried for patients presenting between 1998 and 2002 with tonsil, oropharynx, hypopharynx, and laryngeal primary lesions. Tabulation was made by LNs examined, type of neck dissection performed, and timing of RT. Data from 2441 patients were retrieved. Descriptive statistics were used. Results. One hundred sixty-one patients with RT preoperatively had a median of 20 LNs sampled (0-72). In total, 647 patients receiving no RT had a median of 27 LNs examined (0-88), and 1643 patients receiving RT postoperatively had a median of 29 (0-89). Mann-Whitney P = .02 was derived for RT preoperatively compared with no RT/RT postoperatively. Conclusion. In the head and neck, preoperative RT contributes to lower neck dissection LN yield.