Unilateral neck therapy in the human papillomavirus ERA: accepted regional spread patterns.

BACKGROUND The purpose of this study was to determine whether the incidence of bilateral neck disease tonsillar cancer is rising. METHODS We reviewed tonsillar cancer incidence data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. RESULTS The annual incidence of advanced neck disease (≥N2) with small primary tonsillar cancer is increasing (annual percent change [APC]; p < .05) during 2 evaluable time frames (1988-2003 and 2004-2008). The increase for small primary tonsillar cancer from 2004 to 2008 is associated with increased ipsilateral disease (ie, T1-2N2a-b, APC 10.6%; p < .05) rather than bilateral neck disease (T1-2N2c, APC 5.9%, APC = NS). The increase in bilateral neck disease is less than the overall rise in T1 to 2 tonsillar cancer (APC 7.2%; p < .05). CONCLUSION In the human papillomavirus (HPV) era, bilateral neck disease is increasingly common. This seems to be a consequence of the increasing incidence of tonsillar cancer rather than a new biologic behavior.