Clinical Outcome of Treatment for Hypopharyngeal Cancer at Shiga University of Medical Science Hospital: A Retrospective Study of 107 Patients

We conducted this retrospective study to investigate the treatment outcomes of 107 patients with hypopharyngeal cancer who received their primary treatment at the Department of Otorhinolaryngology-Head and Neck Surgery, Shiga University of Medical Science Hospital, between January 2010 and March 2022. The 5-year overall survival (OS) and disease-specific survival (DSS) rates were 57.1% and 72.5%, respectively. The 5-year OS rates in patients with stage 0, I, II, III, IVA and IVB disease were 100%, 76.9%, 27.8%, 57.1%, 42.1%, and 40.0%, respectively. The 5-year DSS rates in patients with stage 0, I, II, III, IVA and IVB disease were 100%, 92.9%, 83.3%, 85.7%, 55.7%, and 40.0%, respectively. Then, the treatment outcomes of the patients with early-stage cancer (Stage I–II) were examined in 19 patients treated by transoral surgery and 11 patients treated by radiation therapy. The 5-year OS rates and 5-year DSS rates in the transoral surgery group and radiation therapy group were 77.1% and 72.9%, and 90.9% and 87.5%, respectively. The 5-year local control rates (LCRs) in the transoral surgery group and radiation therapy group were 27.2% and 63.5%, respectively, being lower in the transoral surgery group than that in the radiation therapy group. The rate of positive resection margins in the transoral surgery group was 21.9% in cases with Tis-T2 disease, but positive resection margins recurred in only 28.6% of cases. In the transoral surgery group, even some cases with negative resection margins developed local recurrence. With the provision of appropriate treatment after local recurrence, the 5-year OS and 5-year DSS rates in the transoral surgery group were comparable to those in the radiation therapy group. Appropriate evaluation of the resection margins in these patients during transoral surgery is important and the our method of evaluation needs to be improved.