RESUMEN
Objective:To investigate the clinical diagnosis,mechanism and treatment for second malignant tumors (SMTs) of head and neck induced by radiotherapy.Methods:18 cases of SMTs of head and neck following radiotherapy were studied retrospectively.Results:1 patient was dead during the second treatment,3 patients died at 9 months,1 year and 3 years after the second treatment,respectively.All of the 4 patients died of SMTs.Of the remaining 14 patients,1 is being treated at present,the rest 13 patients surviving free of disease up to now.1 patient has survived for more than 7 years since the second treatment.Conclusion:SMTs induced by radiation is the most serious complication of radiotherapy.The key to the successful management of this difficult disease is early detection and expedient treatment.The surgical operation is the first choice for these patients.The radiotherapy may be performed again for SMTs of head and neck when the patients are not suitable for operation.