Background: New criteria for classifying nasopharyngeal carcinoma were defined in the 5th edition of the American Joint Committee on Cancer (AJCC) staging manual. We investigated the clinical implications of the new system by comparing it with the 4th edition in a cohort of pediatric undifferentiated nasopharyngeal carcinoma (UNPC).
Patients and methods: We retrospectively restaged 54 patients younger than 17 years who had biopsy-proven UNPC, treated between 1965 and 1999 in a single institution.
Results: Using the 5th edition an overall downstaging of the population according to T status, N status, and stage grouping was evident along with a better correlation with likelihood of survival. The comparison between local and advanced disease according to T stage (T1+T2 vs. T3+T4) became highly significant in the new system (P = 0.0011 vs. P = 0.067 in the 4th edition).
Conclusions: As far as prognostic categories are concerned, the 5th edition of the AJCC staging manual appears to be an improvement over the previous classification, even though for pediatric patients a uniform distribution among stages cannot be observed because most children present with advanced disease. The overall downstaging should be taken into consideration for the stratification of patients in future trials.