Different staging systems for SEER cause-specific survival (CSS) and overall survival (OS) of SEER patients with hypopharyngeal cancer.

†The P value for Log-rank χ2 tests of cause specific survival was less than 0.001.‡Being calculated using the multivariates Cox regression model for cause specific survival with either N classification or R classification and variates listed at Table 4 as covariates.#The P value for Log-rank χ2 tests of overall survival was less than 0.001.*Being calculated using the multivariates Cox regression model for overall survival with N classification or R classification and variates listed at Table 4 as covariates.