Breast cancer patients treated with radiotherapy after surgery are prospectively enrolled. Thyroid function is evaluated mainly by the measurement of thyroid-stimulating hormone (TSH), free triiodo-thyronine (FT3) and free thyroxine (FT4). Thyroid function is regularly assessed before and after radiotherapy. The radiation technique and thyroid dose parameters are assessed. Development of subclinical or biochemical hypothyroidism is noted. The incidence and risk factors of hypothyroidism is analyzed. The dose-volume constraints that correlate with functional impairment of the thyroid in breast cancer patients treated with radiotherapy is discussed.
This study is to prospectively investigate the incidence of hypothyroidism after postoperative radiotherapy and identify risk factors for development of hypothyroidism. Patients with breast cancer treated with surgery followed by radiotherapy is enrolled. Thyroid function was assessed at baseline and different times after radiotherapy. The radiation technique, thyroid dose parameters and hypothyroidism are prospective evaluated, and the dose-effect relationship is analyzed.