[A case of advanced adenocarcinoma of the ethmoid sinus treated by chemoradiation with S-1].

We report a case of advanced adenocarcinoma in the left ethmoid sinus invading the frontal sinus, the frontal skull base and the orbits(T4bN0M0 and Stage IVB). With the goal of functional preservation, we carried out radiation therapy with total 60 Gy irradiation and chemotherapy with S-1 80 mg/body/day before a radical operation. The tumor clinically disappeared without surgical treatment, and there was no sign of recurrence for 2.5 years. When we decide the treatment policy for advanced adenocarcinoma of the ethmoid sinus, chemoradiotherapy wit S-1 might be one of the effective treatments before radical operation to control the disease with preservation of functions.