Thyroid and parathyroid dysfunction after total laryngectomy in patients with laryngeal carcinoma.

The objective of this study is to investigate thyroid and parathyroid functions in patients with laryngeal carcinoma after total laryngectomy with hemithyroidectomy with or without irradiation, and to determine if irradiation when following surgery has an additive effect contributing to either or both glands hypo function. This study included 17 patients with laryngeal squamous cell carcinoma who were subjected to surgery. Nine of them were further justified for postoperative radiotherapy as well. All patients were subjected to Clinical assessment, including adequate history taking and physical examination, to detect the presence of hypothyroidism or hypoparathyroidism. Laboratory assessment of thyroid function included TSH and T4 assay, and parathyroid function included corrected serum calcium and parathormone levels. Eight (48 %) patients were treated with surgery alone, and 9 (52 %) patients received postoperative radiotherapy. In this study, 13 out of the 17 patients (78 %) were found to be hypothyroid and 4 (22 %) were euthyroid, while 7 (42 %) were found to have hypoparathyroidism. The study showed; among the 8 patients who were treated by surgery only, 5 (62.5 %) of them developed hypothyroidism and 3 (37.5 %) were euthyroid and 3 (37.5 %) developed hypoparathyroidism and 5 (62.5 %) were normal. Among the 9 patients who were treated by surgery and radiotherapy, 8 (88.9 %) developed hypothyroidism and 1 (11.1 %) was euthyroid and 4 (44.4 %) developed hypoparathyroidism and 5 (55.6 %) were normal. The study confirms the development of hypothyroidism with or without hypoparathyroidism after total laryngectomy with a higher incidence in those treated by combined surgery and radiotherapy and in supraglottic tumors.