This excellent study by Adam et al. contributes to a growing body of literature supporting thyroid lobectomy for low risk, small, differentiated thyroid tumors. I should say this represents a shift back toward lobectomy. Total thyroidectomy became the procedure of choice for nearly all differentiated thyroid tumors over the last 2-3 decades in part because of the landmark study by Bilimoria et al. (Surgery 2007;142:906-14).
Now the tide is shifting back the other direction.
I do not mean to imply that passing trends drive how we treat thyroid cancer. Mortality rates from differentiated thyroid cancer remain extremely low. This makes measuring any differences in mortality challenging. The outcome can differ depending on the cohort and the other variables included in the modeling. Recurrence is the real driver of morbidity in thyroid cancer, with anywhere from 10%-30% of patients experiencing a recurrence. Unfortunately, large national cancer registries do not capture recurrence very well.
This study controlled for many tumor features that will also impact disease specific survival apart from just the treatment received. The follow-up time is also impressive. So, if we are to undertake a more nuanced and stratified approach to determining the extent of surgery, there are a few things to consider. The first is patient selection.
In this study and in a growing body of retrospective, single institution studies looking at lobectomy for low-risk cancers, one must remember that these patients are selected based on other tumor features (multifocality, extrathyroidal extension, etc.) and not just size alone. Remember that 30%-40% of patients with papillary thyroid cancer will have multifocal disease.
The second is that successfully treating thyroid cancer patients with lobectomy requires buy-in from all parties involved - surgeons, endocrinologists, and, most importantly, the patient. Everyone must be comfortable with omitting radioactive iodine, detectable thyroglobulin levels, and following the remaining lobe with ultrasound. Some patients will not be comfortable with this and may choose to undergo total thyroidectomy. Even if we surgeons agree to shift back toward less aggressive surgery, we cannot do so in isolation.
Dr. David F. Schneider is an associate professor and the director of endocrine surgery research in the department of surgery, University of Wisconsin, Madison. He has no conflicts to disclose.
