[Thyroid function alteration in patients with radiation therapy of the neck]. / Alteración de la función tiroidea en los pacientes en los que se realizó radioterapia cervical.

INTRODUCTION: The aim of this study is to determine whether the incidence of hypothyroidism in patients with Head and Neck Cancer who have undergone neck radiotherapy justifies the inclusion of thyroid function monitoring in the pre-operative and follow-up evaluation protocols. MATERIAL AND METHODS: A retrospective study was conducted with all the patients seen in the Oncology Section of the Otorhinolaryngology Department in the "Hospital de Clínicas", Montevideo, Uruguay, from January 1970 to May 2008. A total of 550 case records were analyzed. Of the 550 patients, 188 were excluded due to the fact they had not received radiotherapy as part of their treatment and 362 were included in the study. Of these, 55 patients had thyroid stimulating hormone (TSH) level determination after treatment with radiation therapy. Hypothyroidism was defined as a TSH value greater than or equal to 4.5 mIU/L, regardless of whether or not any symptoms were presented. RESULTS: 36.4% of the patients were diagnosed as having clinical or sub-clinical hypothyroidism. The type of treatment carried out, particularly whether or not surgical resection was performed, was found to be the most significant predictive factor for the development of hypothyroidism (P=0.054). CONCLUSION: Monitoring of the thyroid function on a six-month or annual basis, at least during the first 5 post-treatment years, has to be included in the follow-up and control protocols of every patient undergoing neck RT, and patients with TSH values over 4.5 mIU/L should be referred to the endocrinologist for hormone replacement, whether they present symptoms or not.

Alteración de la función tiroidea en los pacientes en los que se realizó radioterapia cervical / Thyroid function alteration in patients with radiation therapy of the neck

Introducción: El propósito de este trabajo es determinar si la incidencia de hipotiroidismo en los pacientes con cáncer de cabeza y cuello en los que se realizó radioterapia cervical justifica la inclusión de la monitorización de la función tiroidea en los protocolos de valoración preoperatoria y de seguimiento. Material y métodos: Se realizó un estudio retrospectivo de todos los pacientes atendidos en la Sección Oncológica del Departamento de Otorrinolaringología del Hospital de Clínicas Montevideo, Uruguay, desde enero de 1970 a mayo de 2008. Se revisó un total de 550 historias clínicas. Del total de 550 pacientes, se excluyeron 188 pacientes dado que no habían recibido radioterapia (RT) como parte del tratamiento, y 362 fueron incluidos en el estudio. Cincuenta y cinco pacientes tenían dosificación de hormona estimulante de la tiroides (TSH) postratamiento con RT. El hipotiroidismo fue definido como un valor de TSH mayor o igual a 4,5mU/l, independientemente de si presentaba o no síntomas. Resultados: Se encontró un 36,4% de pacientes con hipotiroidismo clínico o subclínico. Se determinó que la modalidad de tratamiento efectuado, en especial si se realizó resección quirúrgica o no, es el factor predictivo más significativo de desarrollo de hipotiroidismo (p = 0,054). Conclusión: La monitorización de la función tiroidea debe ser incluida en los protocolos de seguimiento y control de todos los pacientes en los que se realice RT de cuello, semestral o anualmente, por lo menos durante los primeros 5 años postratamiento, y derivar al endocrinólogo para el reemplazo hormonal a los pacientes con TSH mayores a 4,5mU/l, tengan o no síntomas (AU)

Introduction: The aim of this study is to determine whether the incidence of hypothyroidism in patients with Head and Neck Cancer who have undergone neck radiotherapy justifies the inclusion of thyroid function monitoring in the pre-operative and follow-up evaluation protocols. Material and methods: A retrospective study was conducted with all the patients seen in the Oncology Section of the Otorhinolaryngology Department in the Hospital de Clínicas , Montevideo, Uruguay, from January 1970 to May 2008. A total of 550 case records were analyzed. Of the 550 patients, 188 were excluded due to the fact they had not received radiotherapy as part of their treatment and 362 were included in the study. Of these, 55 patients had thyroid stimulating hormone (TSH) level determination after treatment with radiation therapy. Hypothyroidism was defined as a TSH value greater than or equal to 4.5mIU/L, regardless of whether or not any symptoms were presented. Results: 36.4% of the patients were diagnosed as having clinical or sub-clinical hypothyroidism. The type of treatment carried out, particularly whether or not surgical resection was performed, was found to be the most significant predictive factor for the development of hypothyroidism (P=0.054). Conclusion: Monitoring of the thyroid function on a six-month or annual basis, at least during the first 5 post-treatment years, has to be included in the follow-up and control protocols of every patient undergoing neck RT, and patients with TSH values over 4.5mIU/L should be referred to the endocrinologist for hormone replacement, whether they present symptoms or not (AU)