Depth of mediastinal extension can predict sternotomy need for substernal thyroid goiters

Surgical excision of substernal thyroid goiters is usually achieved through a conventional transcervical approach, and transthoracic excision is rarely necessary. Currently, there are no clear guidelines for substernal thyroid goiters that may require a transthoracic approach. This study examined what preoperative factors were significantly associated with transthoracic surgical excision for substernal thyroid goiters.

A retrospective review of prospectively collected data of 109 patients with substernal thyroid goiters from a single institution was performed. The patients were stratified by transcervical and transthoracic approaches for substernal thyroid goiters. The factors possibly predictive of a transthoracic approach, including substernal extension beyond the thoracic inlet, patient-reported symptoms, tracheal deviation, and malignancy, were analyzed. Demographics including age, sex, and race, among others, were also studied.

Of 1,080 patients who underwent surgical resection for multinodular goiter, there were 109 (10%) patients with substernal thyroid goiters. Of the substernal thyroid goiter group, 11 (10%) patients underwent partial sternotomy, whereas 6 (5.5%) underwent total sternotomy. On logistic regression, only substernal component of the thyroid goiter extending beyond the sternal notch into the mediastinum was statistically significant in predicting sternotomy (odds ratio 3.43, confidence interval 1.65-6.41, P < .001). Substernal thyroid goiters with mediastinal extension of ≥5 cm beyond the sternal notch showed a sensitivity of 94% and specificity of 86.5% to predict need of sternotomy.

Patients with substernal thyroid goiters who exhibit progressive enlargement and/or compressive symptoms should undergo surgical excision. Although most are removed through the conventional transcervical approach, substernal thyroid goiters with a depth of mediastinal extension ≥5 cm have a high likelihood of requiring sternotomy.