Objective: Differentiated thyroid cancer (DTC) is 1 of the most common cancers in adolescents and young adults (AYA, ages 15-39). Although most AYAs with DTC are considered low risk compared to older patients, there are no specific postoperative radioiodine (RAI) treatment recommendations despite the potential adverse effects specific to this age group, namely secondary malignancies and fertility difficulties. This study compares factors influencing RAI utilization in AYA and older patients.
Methods: A total of 5,687 primary DTC patients were identified from the SEER (Surveillance, Epidemiology, and End RESULTS) database between January 1, 2004 and January 31, 2009. The 2009 American Thyroid Association (ATA) guidelines were used to classify patients as low (LR) or intermediate/high risk (IHR) based on tumor characteristics. Multivariate logistic regression analysis was performed.
Results: Overall, 56.9% of AYA (n = 1,963) patients received postoperative RAI compared to 52.2% of older (n = 3,724) patients (odds ratio [OR]: 1.21, 95% confidence interval [CI]: 1.09-1.35, P = .001). For AYA patients, having a total thyroidectomy (TTx) (OR: 3.53, 95% CI: 2.7-4.61, P<.001) predicted RAI in a multivariate model whereas LR status (OR: 0.52, 95% CI: 0.43-0.63, P<.001) and northeast residence (OR: 0.39, 95% CI: 0.29-0.52, P<.001) decreased the probability. All 3 factors similarly affected older patients in addition to an increased likelihood after lymph node (LN) dissection. Additionally, after selecting for TTx (n = 1,077), no factor influenced the use of RAI for AYA patients, whereas LR (OR: 0.30, 95% CI: 0.21-0.43, P<.001) and northeast residence (OR: 0.39, 95% CI: 0.19-0.79, P = .008) were associated with decreased RAI use in older patients.
Conclusion: Despite their excellent prognosis, AYA thyroid cancer patients are more likely to receive postoperative RAI compared to older patients. Increased awareness of the unique survivorship implications for AYA patients will be an important aspect to address going forward.