Feasibility of Tomotherapy to spare the cochlea from excessive radiation in head and neck cancer.

We would like to evaluate the effectiveness of Tomotherapy for decreasing radiation dose to the cochlea in head and neck cancer patients. A retrospective review of 72 patients undergoing radiation for head and neck cancer was performed. Cochlea dose was compared between 20 patients treated with conventional intensity modulated radiotherapy (IMRT) and 52 treated with Tomotherapy. A review of literature was performed to assess cochlea dose reported with the IMRT technique for head and neck cancer. Mean total cochlea dose was 36 Gy for IMRT compared to 12.1 Gy for Tomotherapy (p=0.002). Mean right cochlea dose was respectively, 16.6 and 6.2 Gy for IMRT and Tomotherapy (p=0.007), and 19.3 and 5.9 Gy for the left. Cochlea (p=0.002). Mean cochlea dose reported in the literature ranged from 16 to 55 Gy with IMRT for head and neck cancer. Helical Tomotherapy for head and neck cancer may significantly decrease radiation dose to the cochlea without sacrificing target volume coverage.