Journal of Cell Science & Therapy
Open Access

Abstract

Relationship between TSH Level and Effective Half-life of I-131 in Differentiated Thyroid Cancer Patients

John E. Ejeh and Kayode S. Adedapo

The retained activity and Effective half life at 24h of therapeutic 131I in patients with Differentiated Thyroid Cancer (DTC) after total and non-total (sub-total, near-total, partial thyroidectomy and lobectomy) thyroidectomy were compared for patients in these 2 surgical groups. A total of 82 patients (61 females and 21 males) mean age 37.2 ± 9.3 years, mean weight 70 ± 15.6 Kg were considered in this study. 58 patients (70.73%) had papillary Cancer and 24 (29.27%) had follicular cancer. Out of 82 patients, 37 had total thyroidectomy while 45 had non total thyroidectomy (sub-total-29, near total- 10, partial thyroidectomy-4 and lobectomy- 2). 6 patients (7.3%) had metastases. The retained 131I activity (as a percentage of the administered dose in MBq) was 4.61% - 44.56% for patients with total thyroidectomy (mean-26.91 ± 12.57%) compared to 10.18% - 55.36% for patients with non-total thyroidectomy (mean-32.41 ± 12.57%). (p < 0.05) The effective half life ranged between 0.20 – 0.86 days for patients with total thyroidectomy (mean- 0.51 ± 0.21 days) and 0.20 – 1.17 days for patients with non-total thyroidectomy (mean- 0.62 ± 0.27 days). There is no significant difference in the mean effective half lives for the two groups of patients (p = 0.032). Our data suggests that exposure to radiation after ingestion of 131I is similar in both groups studied.