Outer cortex thyroid cartilage invasion vs gross extrathyroidal extension in T4a carcinoma larynx: Are they the same entity?

Abstract

We read the article by Dwivedi et al.[1] with great interest. In the past, total laryngectomy was considered the gold standard treatment for carcinoma larynx regardless of the stage. As the science of conservation laryngectomy, and organ preservation by non-surgical modalities[2] has evolved, total laryngectomy was deemed suitable for very advanced, i.e., T4a lesions of the larynx. T4a is any erosion of the outer cortex of the thyroid cartilage or beyond. This outer cortex erosion can be minimal or gross with soft tissue involvement. The accuracy of computed tomography for detecting gross extrathyroidal extension will obviously be 100%.[3] Now, the question arises as to how to accurately identify early outer cortex erosion of the thyroid cartilage when there is no soft tissue involvement. Guo et al.[4] have beautifully described the computed tomography-based radiomics features for the prediction of thyroid cartilage erosion in laryngeal cancer. A mention of the cases of early outer thyroid cartilage erosion in the study by Dwivedi et al.[1] and their true detection on histopathology would have been appreciated. Of the 30 patients included in this study, nine patients had T2 disease and four had T3 disease. As all patients included in the study underwent total laryngectomy, could they have been offered organ preservation, either medically or surgically? Additionally, the role of computed tomography scans in accurately identifying outer cortex erosion with gross extrathyroidal extension in patients who are post-chemoradiation should be carefully assessed, in view of post-chemoradiation changes in the larynx. Magnetic resonance imaging and a positron emission tomography-computed tomography scan would be valuable to help differentiate edema from tumor in the salvage setting. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.