Intensity Modulated Radiation Therapy Allows Better Swallowing Function Than Conventional Radiation in Patients With Advanced Head and Neck Squamous Cell Carcinoma (HNSCC)

Materials/Methods: Between 2001 and 2010, 2232 patients were treated with radiation therapy for head and neck malignancy. Among them, 59 patients received dental implantation. We found 34 implants in 8 patients which were placed in previously irradiated area. Their characteristics and clinical outcome were retrospectively reviewed. Thirty-one implants were placed after postoperative radiation, 3 implants were placed after sequential chemotherapy and radiation therapy. All patients had a preradiation therapy dental evaluation and dental care. Sixteen implants received 3D conformal radiation therapy, 18 implants received IMRT. One patient with 1 implant had diabetes mellitus (DM), one patient with 2 implants had a history of smoking and alcohol and one patient with 11 implants had both DM and a smoking and alcohol consumption. Nineteen implants were placed in the maxilla and 15 implants were placed in the mandible. Results: The median age of patients was 58 years (range, 46-66 years) and the median follow-up time after implant therapy was 25 months (range, 1399 months). The oral malignancies included 5 squamous cell carcinoma (subsite: 1 maxillary sinus, 1 mobile tongue, 1 tonsil, 1 gingiva and 1 primary unknown cancer), 1 adenoid cystic carcinoma, 1 salivary gland duct carcinoma and 1 malignant lymphoma. There were 1 T1, 3 T2, 2 T3, 1 Tx tumors and 3 N0, 2 N1, 2 N2 tumors in this materials. The median total dose was 59 Gy (range, 30.6-66.6 Gy), the median doses at implant site was 36.5 Gy (range, 10-60 Gy). The median time interval between radiation and implant placement was 51 months (range, 10-95 months). In the patient who had DM and a history of smoking and alcohol, mean time interval between radiation and implant was 62 months. Recurrence was not observed in all patients. In all cases, the implant remained functionally stable without any complication at last follow-up. Conclusions: Dental implant after radiation is feasible in selected patients with good prognostic factors, such as longer time interval between radiation and implant placement and pre-radiation therapy dental care. Author Disclosure: H. Han: None. J. Cha: None. C. Lee: None.