A risk-adapted approach to the use of radioactive iodine and external beam radiation in the treatment of well-differentiated thyroid cancer.

BACKGROUND Both radioactive iodine (RAI) and external beam radiation therapy (EBRT) offer important clinical benefits in properly selected patients with differentiated thyroid cancer. With the increased emphasis on a risk-adapted model for the management of thyroid cancer, it is important to identify which patients are most likely to benefit from radiation therapies given in the adjuvant setting and as treatment of gross residual disease. METHODS This review compares the authors' current management practices with the recommendations of published guidelines from both the National Comprehensive Cancer Network and the American Thyroid Association. RESULTS Because of the lack of prospective randomized studies on either RAI or EBRT in differentiated thyroid cancer, recommendations must be based on retrospective cohort studies that vary in selection criteria, histologies, sample size, inclusion criteria, and follow-up. CONCLUSIONS RAI has an important adjuvant therapy and treatment function in properly selected patients. Likewise, EBRT is associated with increased locoregional control and palliative therapeutic effects in high-risk patients.