The value of CEUS, CT and MRI in assessing thyroid cartilage invasion in patients with laryngeal squamous cell carcinoma

Abstract

Background: Imaging staging of local laryngeal cancer spread plays an important role in choosing suitable treatment strategy which can affect the quality of life. The main diagnostic radiology exams are contrast-enhanced computed tomography (CECT) and magnetic resonance imaging (MRI), however cross-sectional modalities sometimes might have false-positive results, especially in detection of non-ossified thyroid cartilage invasion. Contrast-enhanced ultrasound (CEUS) has a potential in assessing non-ossified thyroid cartilage invasion. Purpose: to assess the value of CEUS, CECT, MRI in detection of non-ossified thyroid cartilage invasion. Methods: Twenty-three patients with laryngeal squamous cell carcinoma with suspected invasion to non-ossified thyroid cartilage initially had CECT, followed by CEUS and eighteen of the patients also had MRI before surgery. Five patients had more than one possible invasion site. The imaging findings of laryngeal carcinoma were evaluated and compared with the postoperative histopathological findings, which were chosen as a gold standard. The dependence of possible thyroid cartilage invasion on laryngeal carcinoma local and distant spread were evaluated. Results: In total 9 thyroid cartilage invasion sites were detected on histopathological examination. The sensitivity, specificity, and accuracy in detection of thyroid cartilage invasion were 88.9%, 78.9%, and 82.1% for CEUS, 66.7%, 78.9%, and 75.0% for CECT, and 100.0%, 50.0%, and 61.9% for MRI, respectively. Our study showed that CEUS and CECT are more accurate than MRI (P<0.05), there was no statistically significant difference between CEUS and CECT. Also, there was tendency of false positive results in CEUS and CECT when laryngeal carcinoma was more locally disseminated. Thyroid cartilage invasion did not show dependence on distant spread of disease. Conclusion: CEUS showed high diagnostic value in detection of non-ossified thyroid cartilage invasion comparing with MRI and could be used as a complementary study to CECT especially in less locally disseminated laryngeal cancer.