Clinical-severity staging system for oropharyngeal cancer: Five-year survival rates

Objective: To improve the classification and survival estimates for patients with oropharyngeal cancer by combining cancer symptom severity and comorbidity with the current TNM cancer staging system. Design: Retrospective medical record review using explicit coding criteria. Setting: University medical center. Patients and Methods: Two hundred ninety-six patients receiving initial treatment from January 1, 1980, to December 31, 1989. Multivariate analysis identified patient factors that had a significant impact on 5-year survival. These patient factors, symptom severity and comorbidity, were combined with cancer stage to create a composite clinical- severity staging system. Main Outcome Measure: Five-year survival. Results: The overall 5-year survival rate was 38% (111/296). Survival by TNM cancer stage was 67% (18/27) for stage 1, 46% (24/52) for stage II, 31% (26/85) for stage III, and 32% (43/132) for stage IV (χ²=10.84: P=.001). When patients were grouped according to the clinical-severity staging system, survival rates were 70% (16 of 23) for stage A, 47% (71 of 152) for stage B, 27% (18 of 67) for stage C, and 11% (6 of 54) for stage D (χ²=34.49; P=.001). Conclusions: Survival estimates can be improved by adding carefully studied and suitably defined patient variables to the TNM cancer stage. The current TNM cancer staging system for oropharyngeal cancer is based solely on the morphologic description of the tumor and disregards the clinical condition of the patient. Cancer symptom severity and comorbidity have a significant impact on survival. Continued exclusion of patient factors leads to imprecision in prognostic estimates and hinders interpretation of clinical studies.