[Effect of irradiation of oral, pharyngeal and laryngeal tumors on thyroid function].

The irradiation of cervical lymphatics in case of oral and pharyngeal carcinomas as well as the irradiation of the operated area in case of laryngeal carcinomas leads to an exposition of the thyroid gland which may result in a dysfunction of this organ. An evaluation of our patients suffering from these tumors and treated during 1984 and 1985 showed a latent hypothyreosis in 46.7% of the patients treated only by cervical irradiation and in 20.7% of the cases treated by radiotherapy of the tumoral focus and additional irradiation of the cervical lymphatics (p less than 0.1). Clinical symptoms were scarcely evident in both groups. For struma prophylaxis, thyreosubstitution with L-thyroxine is recommended.