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

BACKGROUND: 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.

METHODS: 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.

RESULTS: 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.

CONCLUSION: 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.