Effects of Routine and Intermittent Protocols, on Rising TSH level and Clinical Manifestations of Hypothyroidism in Patients with Differentiated Thyroid Carcinoma, Preparing for I-131 Whole Body Scan

It is favorable to obtain an optimal level of TSH with a minimum of clinical manifestations of hypothyroidism in patients with differentiated thyroid carcinoma، preparing for whole body scan.

In this randomized clinical trial that was performed in Ghaem Hospital during a 2 years period، we compared routine and intermittent protocols. In routine protocol، 4-6 weeks after surgery، levothyroxin discontinued and liothyronin prescribed for two weeks، then liothyronin discontinued for 2 weeks and TSH measured. In intermittent protocol، levothyroxin prescribed every other day and after 30 days discontinued and TSH was measured.

Fifty patients were female and 10 cases were male. Fifty-three patients had papillary and 7 cases had follicular carcinoma. Twenty-two patients performed intermittent and 38 patients were on routine protocols. There was no significant difference between two groups in pulse rate، skin dryness، constipation، paresthesia، puffiness and change in weight. There was no significant difference in TSH level between two groups at the end of two protocols. (p=0. 08). We used chi-square، independent and paired t tests for analysis of data and p-value less than 0. 05 was considered as significant.

In this study there was no significant difference in hypothyroid manifestations in intermittent and routine protocols. But exposure to high levels of TSH and its outcomes are less in intermittent protocol.