Endocrine Abstracts

Transarterial chemoembolization (TACE) is widely used for treatment of hepatocellular carcinoma (HCC). During this procedure approximately 20 g of iodide is applied by radiopaque material. There is usually high awareness regarding hyperthyroidism in association with contrast enhanced imaging studies and TACE. To date, however, there are no reports regarding the frequency of hypothyroidism after this procedure, although high doses of iodide can also inhibit the synthesis of thyroid hormones (Wolff Chaikoff effect).

We retrospectively evaluated a cohort of patients with HCC treated by TACE at our center from 1997 to 2007. Out of 107 patients with histologically proven HCC, 65 had TSH measured before and after at least one TACE. Treatment was performed one to seven times. Twelve out of 65 patients (18.5%) had a suppressed TSH. Two were treated for hyperthyroidism, 10 had subclinical hyperthyroidism, either before or after TACE.

Surprisingly, 8 out of 65 patients (12.3%) developed an elevated TSH after the TACE (mean TSH 19.96 μU/ml, range 4.59–76.66). Two of them displayed transient hypothyroidism with normalization of TSH within months. The course of hypothyroidism in the other 6 patients was lost to follow-up. TPO antibodies were only measured in two patients, one was negative and the other was antibody positive.

The high prevalence of hypothyroidism after TACE should lead to enhanced clinical suspicion of this disorder in these patients.