U. Uma Maheswara Reddy1 , Sameer Hussain K.M.2
BACKGROUND This study aims to assess the changes in serum TSH (Thyroid-Stimulating Hormone) in subjects with head & neck carcinoma treated with External Beam Radio-Therapy (EBRT) and study the usefulness of the serum TSH test to identify patients who develop early hypothyroidism in these subjects. METHODS This study involved assessing serum TSH in 50 patients diagnosed with biopsyproven squamous cell carcinoma in the head & neck region treated with external beam radiotherapy (EBRT). The study was designed as a prospective non interventional observational study. All patients underwent serum TSH test before the start of the radiation, at 2 months after the radiation and at 6 months after the radiation. All documented serum TSH levels were taken up for analysis. RESULTS Patient population was characterized by the distribution of patients in subsite of oral cavity in 18 (36 %) patients, hypopharynx in 11 (22 %) patients, larynx in 11 (22 %) patients, oropharynx in 9 (18 %) patients, and nasopharynx in 1 (2 %) patient. 12 (24 %) subjects were in Stage II, Stage III in 34 (68 %) subjects, and Stage IV in 4 (8 %) subjects. Mean TSH before radiotherapy was 1.93 ± 0.72 IU / mL. The mean TSH after 2 months of radiotherapy was 2.25 ± 0.97 IU / mL. The mean value after 6 months was 2.5 ± 1.3 IU / mL. The difference between the mean TSH values of 2 months and 6 months compared to baseline TSH is statistically significant (p < 0.0001 between 2 months and baseline and p < 0.0001 between 6 months and baseline). There was a 17 % increase in the TSH levels after 2 months of radiotherapy and a 30 % increase after 6 months of radiotherapy. CONCLUSIONS There is an increase in the serum TSH values both after 2 months and after 6 months of radiation and also may help in identifying patients with impending hypothyroidism at the early stage.
