Brain Metastases From Differentiated Thyroid Cancer in the Era of Targeted Therapies: A Multi-Center Retrospective Cohort

Background: Brain metastases (BM) of differentiated thyroid carcinoma (DTC) are associated with unfavorable prognosis. This study evaluated BM management strategies and patients' outcomes. Methods: A retrospective review of patients diagnosed with DTC and BM at Tel Aviv Sourasky and Rabin Medical Centers between 1985 and 2024. Clinical features, histopathology, treatments, and survival data were collected. Results: Twenty patients were identified: 11 (55%) had papillary thyroid carcinoma, 8 (40%) had follicular carcinoma and 1 had Hurtle cell carcinoma. BM treatments included neurosurgical resection (n = 9), stereotactic radiosurgery (n = 14), and whole-brain radiotherapy (n = 6). Median survival following BM diagnosis was 16.2 months. Patients who did not undergo surgical resection had significantly shorter survival than those whose BM were resected (13 vs. 80 months, p = 0.03). Survival was also worse among patients receiving systemic therapy at the time BM developed (8.9 vs. 80 months, p = 0.0001). Conclusion: Unresected BM of DTC and those arising during systemic therapy portend high mortality.