Management and follow-up of differentiated thyroid cancer not submitted to radioiodine treatment: a systematic review

INTRODUCTION: The treatment of differentiated thyroid cancer (DTC) has been changing. In low (LR) and intermediate (IR) risk DTC, surgery is becoming more conservative and the usefulness of radioiodine (I-131) has been questioned. An increasing number of patients are treated with lobectomy or total thyroidectomy (TTx), but without I-131. Consequently, the management and the follow-up of these patients need to be revised. EVIDENCE ACQUISITION: We reviewed the available data about the management of these growing categories of patients. We focused on the emerging roles of the conventional tools in the follow-up [thyroglobulin (Tg), thyroglobulin antibodies (TgAb) and neck ultrasound (US)]. Moreover, we evaluated the changes in the use of levothyroxine (L-T4) therapy, and the role of the ongoing risk re-stratification. EVIDENCE SYNTHESIS: Tg, TgAb and neck US continue to represent the cornerstone of the follow-up, however, a change in their interpretation is needed. In particular. the absolute value of Tg and TgAb lost their clinical meaning, while their trend over time acquired a greater value. At variance, the diagnostic role of neck US is becoming very relevant for the early identification of the local recurrences. In addition, L-T4 therapy should be personalized according with the type of surgery, the age of patients and their comorbidities. CONCLUSIONS: Management of DTC treated with lobectomy or Tfx but without I-131 is worldwide changing. The evidences suggest that in this setting of patients with LR or IR of recturences, a relaxed surveillance could represent the most reasonable choice.