CT cross-sectional imaging classification system for substernal goiter based on risk factors for an extracervical surgical approach.

Abstract

The purpose of this study was to identify risk factors for surgical extracervical approach in patients with substernal goiter. We used a novel classification system based on CT scan cross-sectional imaging (CSI) reconstruction. Medical records of 4297 patients with thyroid disease operated on at our department were reviewed. A CSI classification system defined substernal goiter in the cranio-caudal dimension as: grade 1 (above aortic arch), grade 2 (level of aortic arch), and grade 3 (below aortic arch); in the anteroposterior dimension as type A (prevascular), type B (retrovascular-paratracheal), and type C (retrotracheal); in the latero-lateral dimension as: monolateral or bilateral. The prevalence of substernal goiter was 222 of 4297 cases (5.1%). Fifteen of 222 cases (6.7%) required an extracervical approach due to grade ≥2 and/or type C substernal goiter (14 of 15 cases). Ten of 15 patients had malignancy. The CT-CSI classification system allows us to identify risk factors for extracervical surgical approach in substernal goiter. They are grade ≥2, type C substernal goiter, and malignancy.