Objectives — Knowledge of prognostic factors is essential for patient care and research. The objectives of this study were to demonstrate that prognostic factors and their impact can vary depending on study design and to examine the relationships between select prognostic factors.
Methods — Retrospective population-based study of patients with cancer of the hypopharynx in Ontario, Canada, from January 1990 to December 1999 identifying and comparing prognostic factors for different survival outcomes and different subpopulations using Kaplan Meier analysis and Cox Proportional Hazards models.
Results — The impact of prognostic factors varies within subgroups of a study population, varies with treatment decisions, and varies with the outcome of interest.
Conclusions — N and T category were the dominant prognostic factors in hypopharyngeal cancer. Performance status was an independent predictor of survival.