Pretherapeutic Assessment by Multidetector Computed Tomography for Thyroid Cartilage Invasion in Laryngeal Cancer: A Double‑edged Sword

Abstract

Abstract Introduction:Almost one-fourth of head and neck cancers in India are laryngeal cancers. Both conservative and surgical therapeutic approaches are available. According to present tumor-node-metastasis staging protocol, thyroid cartilage invasion is a crucial criterion for diagnosing advanced stages of the disease. A major cartilage invasion depicts T4A stage of disease for which surgical treatment is required. Aims: The present study aims to evaluate the accuracy of multidetector computed tomography (MDCT) in evaluation thyroid cartilage invasion in T3 and T4 stage of laryngeal cancers. Materials and Methods: It is a retrospective analysis done in the Department of Radiology, Pramukhswami Medical College, Anand, Gujarat, on 22 patients of T3 and T4 stage of laryngeal cancer who presented for pretherapeutic MDCT neck evaluation. The MDCT results were retrospectively reviewed and compared with postoperative histopathological results. Statistical analysis was done for each parameter as positive predictive value (PPV) (main statistical parameter), negative predictive value, sensitivity, and specificity. Results: MDCT showed a PPV of 60.00% in detecting any type of thyroid cartilage invasion, 66.66% for major and 33.33% for minor cartilage invasion. Extralaryngeal spread of disease was the most specific marker for cartilage involvement. In total, 31.8% of cases were downgraded in staging by pathology. Conclusion: Overestimation of thyroid cartilage invasion by MDCT is a reality which should be in mind before making final therapeutic decisions. Although crucial, it should not be the sole criteria preventing while making a surgical versus conservative therapeutic call.