Dynamic change of peripheral blood cell in patients with differentiated thyroid cancer before and after 131I treatment

Abstract

Objective To evaluate the kinetics of peripheral blood cells in DTC patients before and after 131I treatment. Methods A total of 64 patients were divided into 2 groups with different therapeutic doses: high-dose group (3.70-5.55 GBq, n=24) and low-dose group (1.11 GBq, n=40). The WBC, neutrophils (NEUT), lymphocytes (LY), RBC and PLT were counted before operation, before 131I treatment, and on 3 d and 7 d after 131I treatment. One-way analysis of variance and two-sample t test were used to analyze the data. Results The counts of WBC and NEUT in both groups along with the LY in high-dose group varied significantly before, and on 3 d and 7 d after 131I treatment(WBC: high-dose group,(6.30±1.04),(8.86±2.07),(6.59±1.64) ×109/L; low-dose group,(6.65±1.48),(10.17±3.04),(7.17±1.57)×109/L; NEUT: high-dose group,(3.75±0.88),(6.42±1.91),(4.53±1.54)×109/L; low-dose group,(3.88±0.90),(7.12±2.77),(4.40±1.17)×109/L; LY: (2.11±0.67),(2.06±0.74),(1.59±0.49)×109/L;F values: 3.88 to 30.20, all P<0.05). The counts of WBC and NEUT in both groups were significantly higher on 3 d after 131I treatment than that before treatment (all P<0.05). The counts of WBC and NEUT in both groups along with the LY in high-dose group decreased significantly on 7 d compared to that on 3 d after 131I treatment (all P<0.05). The counts of LY in high-dose group also significantly decreased on 7 d after 131I treatment than before treatment(P<0.05). The counts of RBC before 131I treatment and LY on 7 d after 131I treatment were significantly different between the 2 groups(t=2.36, -4.30, both P<0.05). Compared with the counts before operation, LY, RBC and PLT were significantly higher (t values: from-4.92 to-2.45, all P<0.05) during hypothyroid state induced by thyroxine withdrawal before 131I treatment. Conclusions Short-term kinetics of WBC and NEUT present as an increase first followed by a decrease after 131I treatment; while LY of high-dose group presents as a gradually decrease. Hypothyroid state induced by levo-thyroxine withdrawal leads to increased counts of LY, RBC and PLT before 131I treatment. Key words: Thyroid neoplasms; Radiotherapy; Iodine radioisotopes; Blood cells