Contrast CT Scan Evaluation of Incidence and Pattern of Thyroid Gland Involvement in Locally Advanced Ca Larynx Modifying the Need of Routine Thyroidectomy with Total Laryngectomy

Abstract

In locally advanced cases of carcinoma larynx, which are being treated with total laryngectomy, routine excision of the thyroid gland (either total or hemi section) is carried out. This study was carried out to evaluate the requirement of routine thyroidectomise with total laryngectomy. An analysis of the final histology of 83 patients, who underwent the traditional treatment, together with the preoperative contrast enhanced CT scan was carried out. Among 58 cases of T3 carcinoma larynx 2 revealed thyroid involvement by metastasis (3.45%), 1 of them was suspected in preoperative CT and confirmed by FNAC. Among 25 cases of T4a carcinoma larynx 6 revealed thyroid involvement by direct extension (24%) with evidence of same in preoperative CT. Risk of thyroid involvement is low in T3 cases (3.45%) and is by metastasis. Risk of thyroid involvement is higher in T4a cases (24%) and is by direct extension. Preoperative CECT is a good tool to predict thyroid gland involvement either by metastasis or by direct spread. This study thus raises doubts about the requirement of routine thyroidectomise in association with total laryngectomies in advanced carcinoma larynx. We thus believe that further investigations, on a larger scale and multi-institutional, is warranted.