Relation of External Beam Radiotherapy Dose with Subclinical Hypothyroidism in Patients undergoing Adjuvant Neck Radiation after Surgery for Squamous Cell Carcinoma of Head and Neck

The objective of this study was to find out the radiation dose relationship with subclinical hypothyroidism in postoperative head and neck squamous cell carcinoma patients, who underwent adjuvant external beam radiotherapy. It a prospective cohort done between June 2018 January 2020. One hundred were fulfilling criteria histological proven (SCC) AJCC stage I III, enrolled. Patients irradiated for 50 Gy bilateral lower on linear accelerator. A CT scan face contrast along T3, T4, TSH before after 4 weeks chemoradiotherapy. All patients kept surveillance every three months one year above-mentioned thyroid function test. Ten (10%) had received less than 30 gland, while 90 (90%) >30 gland. After completion treatment, 27.8% (n = 25) developed among those 90), more None =10), below gland (p= 0.062). Key Words: Head cancer, Neck radiotherapy, Subclinical hypothyroidism.