Bone metastases in newly diagnosed patients with thyroid cancer: A large population-based cohort study

Abstract

BackgroundPopulation-based estimates of the incidence and prognosis of bone metastases (BM) stratified by histologic subtype at diagnosis of thyroid cancer are limited.MethodsUsing multivariable logistic and Cox regression analyses, we identified risk factors for BM and investigated the prognostic survival of BM patients between 2010 and 2015 via the Surveillance, Epidemiology, and End Results (SEER) database.ResultsAmong 64,083 eligible patients, a total of 347 patients with BM at the time of diagnosis were identified, representing 0.5% of the entire cohort but 32.4% of the subset with metastases. BM incidence was highest (11.6%) in anaplastic thyroid cancer (ATC), which, nevertheless, was highest (61.5%) in follicular thyroid cancer (FTC) among the subset with metastases. The median overall survival among BM patients was 40.0 months, and 1-, 3-, and 5-year survival rates were 65.2%, 51.3%, and 38.7%, respectively. Compared with papillary thyroid cancer (PTC), FTC (aOR, 6.33; 95% CI, 4.72–8.48), medullary thyroid cancer (MTC) (aOR, 6.04, 95% CI, 4.09–8.92), and ATC (aOR, 6.21; 95% CI, 4.20–9.18) significantly increased the risk of developing BM. However, only ATC (aHR, 6.07; 95% CI, 3.83–9.60) was independently associated with worse survival in multivariable analysis. Additionally, patients with BM alone (56.5%) displayed the longest median survival (66.0 months), compared with those complicated with one extraskeletal metastatic site (lung, brain, or liver) (35.2%; 14.0 months) and two or three sites (8.3%; 6.0 months). The former 5-year overall survival rate was 52.6%, which, however, drastically declined to 23.0% in patients with one extraskeletal metastatic site and 9.1% with two or three sites.ConclusionCloser bone surveillance should be required for patients with FTC, MTC, and ATC, and extraskeletal metastases at initial diagnosis frequently predict a poorer prognosis.

Osseous Metastases in Thyroid Cancer: Unveiling Risk Factors, Disease Outcomes, and Treatment Impact

“…In this study, a sizable cohort of 120,754 TC patients was examined, and it was discovered that 0.8% of cases presented with bone metastasis at the time of diagnosis, comparable to 0.36% as recently reported by Qi et al [16], 0.5% as recently reported by Zhang et al [6], and 0.97% as recently reported by Liu et al [17]. To our knowledge, this study scrutinizes the largest sample size of DTC (and TC in general) patients with bone metastasis.…”

“…Patients who had bone metastasis were more likely to be over the age of 55, male, Black or Asian or Pacific Islander, or single (never married, separated, divorced, or widowed). Recent studies corroborate the association of older age [6,11,17,18], male gender [6,19], and black race of TC patients [6,11] with bone metastasis. Of these factors, older age is the most supported in the literature.…”

“…Recently, a nomogram was developed to identify high-risk TC patients [11] but did not extensively consider demographic characteristics, such as marital status or income levels. Other recent studies successfully confirmed the influence of select clinical and demographic characteristics on bone metastases but did not find an impact of demographic factors on overall and TC-specific survival [6].…”

“…The decline in survival rates can also be attested to bone metastases concurrently presenting in other regions. A recent population-based study of 64,083 TC patients revealed that TC patients presenting only with bone metastases were associated with a longer survival time (66 months) than those with metastases to bone along with a single (14 months) or multiple (6 months) extraosseous regions [6]. There exist effective treatments for extraosseous metastases, including multikinase inhibitors, 131 I therapy [7], or complete metastasectomy [8] for pulmonary or brain metastases, but limited treatment for bone metastases as the only certified one that currently exists is palliative for symptomatic relief.…”