From the Guidelines
Total thyroidectomy is recommended for differentiated thyroid carcinomas (DTC) with a nodule size of ≥1 cm, or regardless of size if there is metastatic, multifocal, or familial DTC, as well as for medullary thyroid cancer and other aggressive forms of thyroid cancer. The initial treatment for DTC should always be preceded by careful exploration of the neck by ultrasound to assess the status of lymph node chains 1. Less extensive surgical procedures may be accepted in case of unifocal DTC diagnosed at final histology after surgery performed for benign thyroid disorders, provided that the tumor is small, intrathyroidal, and of favorable histological type (classical papillary or follicular variant of papillary or minimally invasive follicular) 1.
Some key points to consider when deciding on total thyroidectomy include:
- The presence of lymph node metastases, which may require compartment-oriented microdissection of lymph nodes 1
- The size and histological type of the tumor, with larger or more aggressive tumors requiring total thyroidectomy 1
- The presence of extrathyroidal extension or vascular invasion, which may require more extensive surgery 1
- The patient's overall health and ability to tolerate surgery, as well as their preferences and values 1
The rationale for total thyroidectomy in these cases includes:
- Facilitating radioactive iodine treatment
- Enabling more accurate thyroglobulin monitoring for recurrence
- Eliminating potential multifocal disease
- Reducing the risk of recurrence
Following surgery, patients will require lifelong thyroid hormone replacement therapy, typically with levothyroxine, with dosing based on weight (typically 1.6-1.8 mcg/kg/day) and adjusted according to TSH levels 1.
It's worth noting that the benefit of prophylactic central node dissection in the absence of evidence of nodal disease is controversial, and there is no evidence that it improves recurrence or mortality rate, but it permits accurate staging of the disease, which may guide subsequent treatment and follow-up 1.
In expert hands, surgical complications such as laryngeal nerve palsy and hypoparathyroidism are extremely rare (<1%–2%) 1.
Overall, the decision to perform a total thyroidectomy should be made on a case-by-case basis, taking into account the individual patient's characteristics, tumor type, and overall health.
From the Research
Thyroid Cancers Requiring Total Thyroidectomy
- Total thyroidectomy is recommended for tumors 1 cm or larger, or for tumors that have metastasized 2
- Total or near-total thyroidectomy is recommended for the treatment of papillary thyroid cancer, except for those with papillary microcarcinoma (< 1 cm) found incidentally after a thyroid lobectomy 3
- Total thyroidectomy should be considered for patients with well-differentiated papillary thyroid cancer 1 cm or greater, as well as for those older than 45 years with ipsilateral multifocal micropapillary cancers 4
Specific Types of Thyroid Cancer
- Follicular thyroid cancer: subtotal thyroidectomy may be considered for tumors less than 3 cm in diameter, but close follow-up is necessary 5
- Papillary and follicular thyroid cancer: total thyroidectomy is the treatment of choice if it can be done without complications, due to its theoretical and practical advantages 6
Key Considerations
- The extent of thyroidectomy and lymphadenectomy are controversial, and the decision should be made on a case-by-case basis 3
- Total thyroidectomy can be performed safely with minimal morbidity by an experienced surgeon 6
- The presence of multifocality, invasion, or metastases may influence the decision to perform a total thyroidectomy 2, 4