Selective use of radioactive iodine in the postoperative management of patients with papillary and follicular thyroid carcinoma.

Radioiodine remnant ablation (RRA) was developed in the 1960s to "complete a thyroidectomy" in the initial management of papillary and follicular thyroid cancer. By the 1990s, it was claimed that RRA diminished recurrence rates in follicular cell-derived cancer (FCDC) patients and decreased the cause-specific mortality (CSM) in patients more than 40 years old at initial surgery. The international trend for the past decade has been towards routine RRA in most FCDC patients. Clinical guidelines have been produced by many societies, promoting such an aggressive stance. Since 1997, many papers have reported improved outcome in FCDC, when patients were subjected to RRA after bilateral lobar resection. However, during the same time-period, it has been recognized that most FCDC patients are truly at "low-risk" of developing life-threatening recurrences. Accordingly, it has been suggested that rational therapy selection should lead to restricting aggressive therapy to those "high-risk" FCDC patients, more predisposed to CSM. To date, no prospective controlled trials exist. Presently available outcome data is based on single institutional or multicenter retrospective studies. This article summarizes the available relevant reported data, and concludes that a selective use of RRA in the postoperative management of FCDC patients is rational, and should actually be encouraged.