Laryngeal preservation for hypopharyngeal cancer by radiotherapy with S-1 and vitamin A (TAR therapy)

The objective of this study was to analyze the outcome of hypopharyngeal cancer patients who underwent triple combination treatment with S-1, vitamin A and radiation (TAR therapy), and to analyze the role of TAR therapy for treating locally advanced hypopharyngeal cancer patients. 146 patients (stage I: 10 cases, stage II: 22 cases, stage III: 23 cases, stage IV: 91 cases) with hypopharyngeal squamous cell carcinoma were treated with TAR therapy (S-1; orally, 65 mg/m²/day, twice a day; vitamin A (retinol palmitate): 50, 000 I U/day, intra-musculary on each day of radiation; radiation: 1.5-2 Gy/day, 5 days/week). Histologic complete responders at 30-40 Gy continued TAR therapy up to 60-70 Gy. Nonresponders at 30-40 Gy underwent surgery. The overall 5-year survival and disease-specific 5-year survival rates were 50.5% and 59% respectively. The cumulative 3-year laryngeal preservation rate for stage I was 100%, 82.5% for stage II, 66.6% for stage III, and 35% for stage IV. Laryngeal preservation was fair in T1/T2 patients (81 %), but not satisfactory in T3/T4 patients (21.4%). S1 is administered orally, and TAR therapy can be conducted in the clinic with low toxicity. However, protocols with high intensity may be necessary to improve laryngeal preservation for locally advanced (T4) hypopharyngeal cancer.