RESUMEN
Despite recent advances in the diagnosis and treatment of head and neck cancer, there has been little evidence of improvement in 5-year survival rates over the last few decades. To determine more accurate trends in site-specific outcomes as opposed to a more general overview of head and neck cancer patients, we analyzed the site-specific data collected in the Surveillance, Epidemiology, and End Results-SEER Public-Use Database 1973-1999. Based on the selection criteria, 96,232 cases were evaluated for trend analysis in incidence, clinical stage, treatment and 5-year survival. During the period 1973-1999, site-specific incidence rates for head and neck cancer changed significantly. Site-specific analysis of survival from 1974-1997 showed significant improvements in 5-year survival rates for cancers of the nasopharynx, oropharynx and hypopharynx (38.1% to 56.7% for nasopharynx, p < 0.001; 36.3% to 49.1% for oropharynx, p = 0.001 and 28.3% to 33.3% for hypopharynx, p = 0.015). The prognosis for early-stage salivary gland cancer during 1983-1997 and late-stage larynx cancer during 1974-1997 also demonstrated improvement (82.7% to 88.5%, p = 0.012 and 22.2% to 38.3%, p = 0.013, respectively). On the other hand, the prognosis for regional stage oral cavity cancer as well as early-stage larynx cancer patients declined during 1983-1997 (49.2% to 43.8%, p = 0.032 and 82.3% to 74.3%, p = 0.002, respectively). Site-specific changes in treatment and staging were also noted. Site-specific analysis allows for a more accurate description of incidence, staging, treatment, and prognostic trends for head and neck cancer.