External Beam Radiotherapy in Differentiated Thyroid Cancer

Differentiated thyroid cancer is treated by surgery, radioiodine treatment, and Thyroid Stimulating Hormone (TSH) suppression. The role of external beam radiotherapy is mainly palliation of radio-iodine non avid metastatic lesions and in inoperable tumors. Metastasis involving weight-bearing bones and vertebral metastasis with impending spinal cord compression are primarily treated by external radiation. External Beam Radiotherapy improves loco-regional control in patients with gross residual disease after surgical resection. Patients with extra-thyroidal disease and positive margins are treated by adjuvant external beam radiotherapy, especially when the post op radio-iodine scan is negative. External beam radiotherapy is the treatment of choice for radio-iodine non avid inoperable loco-regional recurrence. SRS alone or surgery followed by SRS is the preferred treatment for solitary brain metastasis. Whole brain radiotherapy is the treatment of choice for multiple brain metastatic disease.