Linear association between radioactive iodine dose and second primary malignancy risk in thyroid cancer
- 23 February 2023
- journal article
- research article
- Published by Oxford University Press (OUP) in JNCI Journal of the National Cancer Institute
- Vol. 115 (6), 695-702
- https://doi.org/10.1093/jnci/djad040
Abstract
We aimed to investigate whether the risk of second primary malignancy (SPM) in patients with thyroid cancer (TC) receiving radioactive iodine (RAI) therapy rises in a cumulative, dose-dependent manner compared with those not undergoing RAI. Using the Korean National Health Insurance Service National Health Information Database (2002-2019), we investigated hazard ratios of SPM associated with RAI in TC. SPM was defined as a second primary malignancy diagnosed at least 1 year after TC diagnosis. Of 217 777 patients with TC (177 385 women and 40 392 men; mean [SD] age, 47.2 [11.6] years), 100 448 (46.1%) received RAI therapy. The median (IQR) follow-up duration was 7.7 (5.5-10.3) years, and the median (IQR) cumulative RAI dose was 3.7 (1.9-5.6) GBq. From 2004 to 2019, SPM incidence rates were 7.30 and 6.56 per 1000 person-years in the RAI and non-RAI groups, respectively, with an unadjusted hazard ratio of 1.09 (95% confidence interval = 1.05 to 1.13); this rate remained at 1.08 (95% confidence interval = 1.04 to 1.13) after adjustment for multiple clinical confounding factors. Notably, SPM risk increased significantly, from 3.7 GBq with full adjustments, and a strong linear association between cumulative RAI dose and SPM was observed in the restricted cubic spline analysis. Regarding cancer subtypes, myeloid leukemia and salivary gland, trachea, lung and bronchus, uterus, and prostate cancers were the most significantly elevated risks in patients who underwent RAI therapy. This study identified that SPM risk increased linearly in a dose-dependent manner in patients with TC undergoing RAI therapy compared with those not undergoing RAI therapy.This publication has 27 references indexed in Scilit:
- 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 CancerThyroid®, 2016
- Radioactive Iodine Therapy Did Not Significantly Increase the Incidence and Recurrence of Subsequent Breast CancerJournal of Clinical Endocrinology & Metabolism, 2015
- Increased Risk of Leukemia After Radioactive Iodine Therapy in Patients with Thyroid Cancer: A Nationwide, Population-Based Study in KoreaThyroid®, 2015
- Adjuvant radioactive iodine therapy is associated with improved survival for patients with intermediate-risk papillary thyroid cancer.Journal of Clinical Endocrinology & Metabolism, 2015
- The risk of second primary malignancy is increased in differentiated thyroid cancer patients with a cumulative 131I dose over 37 GBqClinical Endocrinology, 2014
- Changes in the Clinicopathological Characteristics and Outcomes of Thyroid Cancer in Korea over the Past Four DecadesThyroid®, 2013
- Common problems related to the use of number needed to treatJournal of Clinical Epidemiology, 2009
- Survival in patients with papillary thyroid cancer is not affected by the use of radioactive isotopeJournal of Surgical Oncology, 2007
- Local and regional control in patients with papillary thyroid carcinoma: specific indications of external radiotherapy and radioactive iodine according to T and N categories in AJCC 6th editionEndocrine-Related Cancer, 2006
- Outcomes of Patients with Differentiated Thyroid Carcinoma Following Initial TherapyThyroid®, 2006