Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Dec;22(4):595-602.
doi: 10.1007/s42000-023-00479-x. Epub 2023 Aug 21.

The effect of radioiodine therapy on blood cell count in patients with differentiated thyroid cancer

Ahmet Numan Demir  1 , Zehra Kara  1 , Cem Sulu  1 , Serhat Uysal  1 , Guldana Zulfaliyeva  2 , Oznur Aydin Atar  2 , Nahida Valikhanova  2 , Tulin Ozturk  3 , Hande Mefkure Ozkaya  1 , Taner Damci  1 , Mustafa Sait Gonen  4
Affiliations

The effect of radioiodine therapy on blood cell count in patients with differentiated thyroid cancer

Ahmet Numan Demir et al. Hormones (Athens). 2023 Dec.

Abstract

Purpose: This study aimed to investigate the long-term effects of radioiodine treatment (RAI) on blood cell counts in patients with differentiated thyroid cancer (DTC) and to describe the characteristics of patients at high risk for blood cell count abnormalities.

Methods: The study included patients with DTC who underwent RAI treatment between 2007 and 2017. Patients with regular complete blood counts for at least 5 years were included, while those with diseases or treatments that could influence blood count parameters were excluded. Blood cell count abnormalities were defined according to the Common Terminology Criteria for Adverse Events version 5.0, and factors influencing these abnormalities were examined.

Results: A total of 225 patients were analyzed. The mean age at diagnosis was 45.8 ± 13.9 years, and 76.5% of patients were female. In the first year after RAI, leukocyte, neutrophil, and lymphocyte counts were significantly reduced compared with baseline values. The leukocyte and neutrophil counts returned to baseline values by the third year, while the decrease in lymphocytes continued until the fifth year. Blood cell count abnormalities developed in 16 patients (7.1%) within the first year after RAI. Risk factors for blood cell count abnormalities within the first year after RAI included male sex, older age, T4, N1, and M1 disease, as well as higher RAI doses. In logistic regression analysis, only RAI dose remained independently associated with blood cell count abnormalities.

Conclusion: These results suggest an association between RAI dose and blood cell count abnormalities, characterized by mild lymphopenia, and indicate that the risk of mild lymphopenia persists over time. Careful consideration should be given when planning high-dose RAI for patients at a high risk of blood cell count abnormalities, such as males with metastatic disease and of advanced age.

Keywords: Blood cell counts; Differentiated thyroid cancer; Lymphopenia; Radioiodine.

PubMed Disclaimer

References

    1. Haugen BR, Alexander EK, Bible KC et al (2016) 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid 26(1):1–133. https://doi.org/10.1089/thy.2015.0020 - DOI - PubMed - PMC
    1. Pacini F, Schlumberger M, Dralle H et al (2006) European consensus for the management of patients with differentiated thyroid carcinoma of the follicular epithelium [published correction appears in Eur J Endocrinol 155(2):385]. Eur J Endocrinol 154(6):787–803. https://doi.org/10.1530/eje.1.02158 - DOI - PubMed
    1. Mazzaferri EL, Jhiang SM (1994) Long-term impact of initial surgical and medical therapy on papillary and follicular thyroid cancer [published correction appears in Am J Med 98(2):215]. Am J Med 97(5):418–428. https://doi.org/10.1016/0002-9343(94)90321-2 - DOI - PubMed
    1. Goldsmith SJ (2011) To ablate or not to ablate: issues and evidence involved in 131I ablation of residual thyroid tissue in patients with differentiated thyroid carcinoma. Semin Nucl Med 41(2):96–104. https://doi.org/10.1053/j.semnuclmed.2010.11.002 - DOI - PubMed
    1. Jonklaas J, Sarlis NJ, Litofsky D et al (2006) Outcomes of patients with differentiated thyroid carcinoma following initial therapy. Thyroid 16(12):1229–1242. https://doi.org/10.1089/thy.2006.16.1229 - DOI - PubMed

Substances