Minimally invasive follicular thyroid cancer (MIFTC) - A consensus report of the European Society of Endocrine Surgeons (ESES)

Background: This paper aims to review controversies in the management of minimally invasive follicular thyroid carcinoma (MIFTC) and to reach an evidence-based consensus. Method: MEDLINE search of the literature was conducted using keywords related to MIFTC. The search term was identified in the title, abstract, or medical subject heading. Available literature meeting the inclusion criteria were assigned the appropriate levels of evidence and recommendations in accordance with accepted international standards. Results were discussed at the 2013 Workshop of the European Society of Endocrine Surgeons devoted to MIFTC. Results: Published papers on MIFTC present inadequate power with a III-IV level of evidence and C grade of recommendation. Several issues demanded a comparison of published studies from different medical reports regarding MIFTC definition, specimen processing, characteristics, diagnosis, prognoses, and therapy. As a consequence, it is difficult to make valuable statements on MIFTC with a sufficient recommendation rating. MIFTC diagnosis requires clearer, unequivocal, and reproducible criteria for pathologist, surgeons, and endocrinologists to use in the management of these patients. If the distinction between MIFTC and WIFTC cannot be made, an expert in thyroid pathologist should be consulted. Conclusion: According to published papers, the following conclusions can be drawn. (a) Candidates for hemithyroidectomy are MIFTC with exclusive capsular invasion, patients <45 years old at presentation, tumor size <40 mm, without vascular invasion, and without any node or distant metastases. (b) Candidates for total thyroidectomy are MIFTC in patients ≥45 years at presentation, tumor size ≥40 mm, vascular invasion present, positive nodes, and positive distant metastases. (c) In the absence of clinical evidence for lymph node metastasis, patients with MIFTC do not require prophylactic lymph node dissection. (d) Radio iodine ablation is indicated in elderly patients (>45 years), large tumor size (>40 mm), extensive vascular invasion, presence of distant synchronous or metachronous metastasis, positive nodes, and if recurrence is noted at follow-up.