Thyroid gland in carcinoma of the larynx and hypopharynx: analysis of factors indicating thyroidectomy.

Background: This prospective study analyzed the factors that could predict thyroid gland involvement in patients suffering from malignancy of the larynx and laryngopharynx.

Methods: Fifty patients underwent total laryngectomy with either ipsilateral hemithyroidectomy or total thyroidectomy in cases with subglottic extent more than 1.5 cm or in patients undergoing total laryngopharyngectomy for hypopharyngeal malignancy. The laryngectomy specimen and thyroid specimen were studied histologically with multiple serial sections.

Results: The majority of patients had glottic involvement followed by supraglottic and hypopharyngeal lesions. The thyroid gland was found to be enlarged and nodular in six patients. One of six patients had frank induration with gross extralaryngeal spread. Our study showed a 2% incidence of thyroid gland invasion by tumour.

Conclusions: The presence of subglottic extension of more than 2 cm, cricoid cartilage invasion, and perithyroidal soft tissue involvement can be considered indicators for sacrificing the whole thyroid gland during surgery.