ASSESSMENT OF HYPOTHYROIDISM IN LOCALLY ADVANCED HEAD AND NECK CANCER TREATED WITH CONCURRENT CHEMO-RADIOTHERAPY

Usha Singh*, Rita Rani, Vinita Trivedi, Richa Chauhan, Abha Kumari and Vasudha Singh

ABSTRACT

Head and neck cancer is 6th most common malignancy world wide.Thyroid gland centrally situated in neck will invariably be included in radiation portal. Tolerance dose of thyroid gland depends upon percentage of thyroid volume receiving radiation.
The present study aimed to evaluate thyroid dysfunction in patients of head and neck cancer treated with concurrent chemoradiotherapy.
This is a prospective non randomized study of 55 patients of locally advanced head and neck cancer patients receiving radiotherapy with median follow up of 2.5 years.
At one month of follow up no hypothyroidism was detected. After six months of treatment hypothyroid were detected in 9% patients .After one year of treatment incidence of hypothyroidism were increased to 36.36% After two years of treatment incidence of hypothyroidism increased to 49.09% out of which 56% patients having clinical hypothyroidism and 44% had sub clinical hypothyroidism.
It was remarkably noted that hypothyroidism were more frequent in female patients in comparison to male. After one year of treatment 54% female developed hypothyroidism while it is observed only in 22.72% male. After two years of treatment 72.72% female had hypothyroidism (P value - 0.0213) while only 43.18% male developed hypothyroidism (P value - < 0.0001, which is highly significant).
Radiation induced hypothyroidism is seen as late complication. Hypothyroidism causes considerable morbidity to patients who undergo chemoradiotherapy. Screening protocol for thyroid dysfunction should be mandatory as routine follow up.

Keywords: Head and neck cancer, hypothyroidism, radiotherapy, subclinical hypothyroidism.