Associated factors of brain metastases and diagnostic yield of staging brain magnetic resonance imaging in anaplastic thyroid cancer

Abstract

Background This study aimed to identify the associated factors for brain metastasis (BM) in patients with anaplastic thyroid cancer (ATC) and estimate the diagnostic yield of staging brain magnetic resonance imaging (MRI) during the initial evaluation of ATC. Methods This retrospective, single-center study included patients newly diagnosed with ATC who underwent brain MRI, from May 2008 to July 2024. The patients were stratified into two groups (BM vs. non-BM). The clinical characteristics of ATC were compared between the two groups using the chi-squared test and multivariable logistic regression analysis. The diagnostic yield of initial staging brain MRI from 2010 to 2024 was calculated. Results A total of 77 patients (61.52±13.19 years old, 37 men) were included. BM was observed in 19 patients (24.7%). The occurrence of BM was significantly associated with extracranial metastasis (p=0.004), especially lung metastasis (p=0.017), and neurologic symptoms (p=0.001). On multivariable logistic regression analysis, after adjusting for age, sex, and primary thyroid tumor size, the presence of extracranial metastases (odds ratio [OR]: 16.09 [2.39–360.70], p=0.019) and neurologic symptoms (OR: 5.95 [1.73–24.08], p=0.007) were independently associated with BM. The diagnostic yield of staging brain MRI during the initial evaluation of ATC was 6.1% (3/49). The diagnostic rate of BM was 26.5% (18/68) in patients with extracranial metastases and 38.9% (14/36) in those with neurological symptoms. Conclusion Routine staging or surveillance brain MRI in patients with extracranial metastasis is likely to offer significant benefits.