[Trends in the Detail of the Stage and Survival Rate in Hypopharyngeal Cancer over 20 Years].

Background: Hypopharyngeal cancer frequently presents at an advanced stage and has one of the worst prognosis among the head and neck cancers. Recently, superficial hypopharyngeal cancers with a good prognosis have been detected with a novel endoscopic technique, such as narrow band imaging. Objectives: To evaluate trends in the detail of the stage and survival rate in hypopharyngeal cancer over 20 years. Patients and methods: Between 1993 and 2012, 722 patients with hypopharyngeal cancer treated at the Osaka Medical Center for Cancer and Cardiovascular Disease were studied retrospectively. The 20-year period was subdivided into 5-year periods; Period A (1993-1997, n=101), Period B (1998-2002, n=123), Period C (2003-2007, n=196) and Period D (2008-2012, n=302). The patients at Stage I-II were divided into superficial cancer as Stage I-IIs and invasive cancer as Stage I-IIi. In every period, a transition of the staging and overall survival rate were compared. Results: The 5-year overall survival in Period A, B, C and D were 34%, 39%, 54% and 60%, respectively. The patients at Stage III-IV in Period A, B, C and D comprised 32%, 36%, 47% and 54%, respectively. Both survival rates improved significantly from Period B to C. The ratio of Stage 0 and Stage I-IIs increased significantly from Period C to D. Whereas the 5-year overall survival rates of Stage 0 and Stage I-IIs were similar (80% vs 88%), the 5-year overall survival of Stage I-IIi was significantly poor. Excluding Stage 0 and Stage I-IIs, the 5-year overall survival had little change from Period C to D. Conclusion: The reason for the improvement in hypopharyngeal cancer prognosis was the prognostic improvement of advanced cancer from Period B to C, and an increase in superficial cancer from Period C to D.