[Radiation associated cancers among head and neck cancer patients].

During a 31-year old period from 1953 to 1983, 2533 patients with head and neck cancers reported to our clinic. There were 16 cases among them of second malignant cancers who were irradiated previously to the benign head and neck lesions. There were also 146 cases of multiple primary cancers including 17 multiple primary intraoral cancer patients and 46 cases of radiation associated cancers. Forty-six radiation associated cancers included three histologically confirmed radiation induced cancers and three histologically confirmed late recurrent cancers.