Total thyroidectomy vs. lobectomy in differentiated thyroid cancer: is there a reasonable size cut-off for decision? A narrative review

Objective: To analyze all the most recent guidelines/consensus as well as papers regarding the relationship between size of tumor, type of surgery, and prognosis, and to try to produce a critical synthesis for real practice. Background: Differentiated thyroid cancer (DTC) is characterized by a wide range of biological behavior. The type of intervention can range from lobectomy (LT) to total thyroidectomy (TT), with tumor size being a point of discussion in choosing the treatment. Methods: We carried out a search on PubMed, EMBASE, and Cochrane Library, looking at all the guidelines and consensus regarding DTC, as well as examining original articles, inserting as our research keys “total thyroidectomy vs. lobectomy in differentiated thyroid cancer” and “hemithyroidectomy in thyroid cancer”. The guidelines and consensus published over the last 5 years were 6 in total: ATA Guidelines, Italian Consensus of Six Italian Societies, United Kingdom National Multidisciplinary Guidelines, ESMO Clinical Practice Guidelines, a Practical Guidance of a Multidisciplinary Panel of Experts, and The Revised Clinical Practise Guidelines on the Management of Thyroid Tumours by the Japanese Association of Endocrine Surgeons. There were 13 papers cited in the guidelines, and we found another 5 original articles, all of which were retrospective studies. Conclusions: The type of initial surgical intervention must of course consider tumor size, but must also take into account all the risk factors, which is paramount in deciding the type of treatment. LT can have some advantages, and can represent an option that can be offered to patients. However, even in the absence of any special risk factors, a review of the literature suggests to us that patients should be informed that LT for tumors of a size between 2 and 4 cm can be associated with an increased risk of LR as well as with a possible reduced OS.