Incidence of hypothyroidism after radiotherapy for nasopharyngeal carcinoma.
OBJECTIVE
The thyroid gland is frequently affected by radiotherapy applied for the treatment of head and neck tumors. Hypothyroidism is observed as a late side effect of radiotherapy, especially seen in the patients who have surgery in the treatment procedure.


METHODS
We evaluated the radiation-induced hypothyroidism for a selected type of head and neck cancer- nasopharyngeal cancer (NPC)-which does not include surgery involving the thyroid gland in the treatment.


RESULTS
We observed 12 patients (14%) who developed hypothyroidism, two of which were subclinical hypothyroidism. The patients with hypothyroidism were statistically significantly younger than the euthyroid patients, but there were no statistically significant differences among the two groups in disease stages, radiotherapy neck doses, and gender.


CONCLUSIONS
We recommend life-long TSH screening after RT to the neck owing to the incidence of RTinduced hypothyroidism and the importance of early thyroid hormone replacement therapy in patients becoming hypothyroid for maintaining optimal quality of life.
Department of Radiation Oncology, Faculty of Medicine, Hacettepe University, 06100 Sihhiye, Ankara, Turkey.
Sükran
S
Ulger
Zekeriya
Z
Ulger
Ferah
F
Yildiz
Enis
E
Ozyar
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006257:Head; D006801:Humans; D007037:Hypothyroidism / Q000188:drug therapy / Q000209:etiology*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D009333:Neck; D011878:Radiotherapy / Q000009:adverse effects*; D012189:Retrospective Studies; D013961:Thyroid Gland / Q000528:radiation effects