Endocrine Abstracts

Aims: Side effects of large dose of radioactive iodine (RAI) therapy for well-differentiated thyroid carcinoma are noted.There were insufficient data regarding bone marrow suppression and inflammatory response in patients with thyroid cancer who received RAI therapy in Asia;

Patients and methods: We performed the study at the Chang Gung Memorial Hospital in Keelung, Taiwan. Patients with papillary or follicular thyroid cancer who received more than 2.6 GBq (70 mCi) RAI were enrolled in this hospital based study. We evaluate the renal function, serum inflammatory marker and bone marrow suppression before and 1 week after RAI treatment. In addition, these analyses were also performed between thyroxine withdrawl and recombinant human thyrotropin (rh-TSH) injection groups.

Results: There have been 101 patients who completed the blood test. The WBC count decreased 1 week after radioiodine treatment compared with that before RAI treatment (6307±1527/ul vs 5476±1439/ul, P <0.001). Among 72 patients with thyroxine withdrawl and 29 patients with rh-TSH injection, the WBC count was lower in patients with thyroxine withdrawl than those with rh-TSH injection although there is not statistically significant (P=0.080). The serum creatinine level is significantly higher in patients with thyroxine withdrawl than those with rh-TSH injection (P<0.001). There is no any difference regarding RBC count, platelet count and serum CRP level between thyroxine withdrawl and rh-TSH groups.

Conclusions: The data gives useful information in thyroid cancer patients taking high dose of RAI treatment, and helps to suggest dose adjustment concerning about radiation safety for the patients.