TNM-based stage groupings in head and neck cancer: application in cancer of the hypopharynx

Background — The purpose of this study was to test the Union Internationale Contre le Cancer (UICC)/TNM category–based head and neck cancer stage grouping systems proposed in the literature for their ability to create clinically relevant prognostic groups of like-patients with cancer of the hypopharynx.

Methods — Population-based retrospective survival study of 595 patients with squamous cell carcinoma of the hypopharynx across Ontario, Canada, from January 1990 to January 2000. The grouping systems of UICC/TNM, T and N Integer Score (TANIS), Hart, Berg, Snyderman, Kiricuta, and Hall were tested and compared for prognostic ability using hazard consistency, hazard discrimination, percent variance explained, outcome prediction, and balance.

Results — All 8 systems predicted disease-specific survival. The system proposed by Snyderman performed the best, and UICC/TNM sixth edition did not perform as well as most.

Conclusion — The UICC/TNM stage group classification, although successful in creating statistically distinct groups, did not perform as well as other stage grouping systems, continuing a theme that has been reported previously.