Long-Term Outcomes and Prognoses of Elderly Patients (≥65-Years-Old) With Distant Metastases From Well-Differentiated Thyroid Cancer During Radioiodine Therapy and Follow-Up

Zhong-Ling Qiu,Yang Wang,Chuang Xi,Hong-Jun Song,Chen-Tian Shen,Zhen-Kui Sun,Quan-Yong Luo,Guo-Qiang Zhang

doi:10.3389/fendo.2020.588024

Zhong-Ling Qiu, Yang Wang + Show 6 more

Open Access

https://doi.org/10.3389/fendo.2020.588024

Copy DOI

Abstract

ObjectiveThe objective of this study was to investigate the clinicopathological characteristics, long-term outcomes, and prognostic factors of elderly patients with distant metastases at initial diagnosis from well-differentiated thyroid cancer (WDTC) during radioactive iodine (131I) treatment and follow-up.MethodsA retrospective review of medical records identified 183 elderly patients with DTC who underwent 131I treatment at our institution between 2006 and 2019.ResultsIn total, 57 elderly WDTC patients with distant metastases were enrolled in this study. After 131I treatment, 32 (56.14%) patients had 131I avidity and 25 (43.86%) had non-131I avidity; 35 (61.40%) cases were classified as radioiodine refractory (RR)-WDTC and 22 (38.60%) as non-RR-WDTC. At the end of follow-up, 25 (43.86%) patients had died and 32 (56.14%) were alive. The 5- and 10-year overall survival (OS) rates were 71.50% and 30.49%, respectively, while the 5- and 10-year disease-specific survival (DSS) rates were 76.89% and 48.71%, respectively. Multivariate analyses showed that gross extrathyroidal extension and RR-DTC were independent prognostic factors for poor OS (P=0.04 and P=0.03, respectively), while gross extrathyroidal extension, extrapulmonary distant metastases, and RR-WDTC were independent prognostic factors for poor DSS at the end of follow-up (P=0.02, P=0.03, and P=0.02, respectively).ConclusionsWDTC with distant metastases at initial diagnosis accounted for 31.15% of all elderly patients with DTC. Gross extrathyroidal extension and RR-DTC were the major factors associated with poor OS; gross extrathyroidal extension, extrapulmonary distant metastases, and RR-DTC were independent prognostic factors for poor DSS in elderly DTC patients with distant metastases.

Highlights

Over the past two decades, differentiated thyroid cancer (DTC) has become the most common endocrine malignancy with the fastest growth rate worldwide [1]
The incidence of distant metastases in elderly DTC patients has significantly increased [4]; to the best of our knowledge, there is little published information on the long-term outcomes of elderly well-DTC (WDTC) patients with distant metastases. To address this issue and raise awareness of this disease, this study reviewed the experience of a single tertiary medical center in China with a relatively large series of elderly (≥65 years) WDTC patients who presented with distant metastases at initial diagnosis
57 (31.15%) elderly WDTC patients with distant metastases were confirmed according to the inclusion criteria

Summary

Introduction

Over the past two decades, differentiated thyroid cancer (DTC) has become the most common endocrine malignancy with the fastest growth rate worldwide [1]. Previous studies have shown that age at initial diagnosis of DTC is the factor most associated with recurrence, survival, and prognosis [3]. Patients have a poorer prognosis and more aggressive DTC, which is characterized by larger tumors, extrathyroidal invasion, and distant metastasis [4]. The AJCC/UICC revised the age cut-off from 45- to 55-years-old in the latest TNM staging system (2016), elderly DTC patients continue to have significantly decreased survival compared with younger patients [5]. Regarding the optimal cut-off value for defining “the elderly” DTC population, 60, 65, and 70 years have been reported in different studies [6, 7]. According to the World Health Organization, most developed countries have adopted the definition of ≥65 years as “the elderly”

Methods

Results

Discussion

Conclusion