RETROSTERNAL GOITRES: A PRACTICAL CLASSIFICATION.

BACKGROUND

There is no standard definition for goitres extending below the thoracic inlet and no clear guidelines for pre-operative planning of surgery. The aim of this study is a practical classification of retrosternal goitres (RSG) based on the anatomical , radiological shape and size of the thyroid.

METHODS

Retrospective analysis of all thyroidectomies performed in a referral centre between January 2012 and December 2016. Patients with RSGs had a pre-operative CT scan of neck/thorax. Imaging was reviewed to establish features to predict the difficulty of delivering the goitre through the neck incision and to advise the best surgical approach.

RESULTS

847 thyroidectomies were performed with n=98 involving RSGs. TypeA (n=47) are RSG with a shape of a "cone" or pyramid with the apex pointing down. Cervicotomy is the usual approach. TypeB (n=39) are goitres with a shape of a "pyramid' with the apex pointing up, cervicotomy with ± manubriotomy or sternotomy ± thoracotomy maybe required. TypeC (n=6) are thyroid enlargements in the mediastinum connected by a pedicle with the thyroid in the neck. A cervical approach ± manubriotomy or sternotomy ± thoracotomy is needed. TypeD (n=6) are true intrathoracic or "forgotten" goitres. Sternotomy is indicated for thyroids in the anterior mediastinum though a thoracic approach for those located in the posterior mediastinum might be needed.

CONCLUSION

The shape and size of goitres is important in carefully planning surgery. CT imaging with cross-sectional reconstruction should be analysed before operation. The proposed classification helps treatment planning and allows comparison of outcomes by anatomical complexity.