Prognostic Stratification of Brain Metastases from Nonanaplastic Follicular Cell–Derived Thyroid Carcinoma: Results of an International Multicenter Retrospective Study
Antonio Prinzi, Evert F.S. van Velsen, Jolanta Krajewska, Magdalena Kolton, Inbar Finkel, Liyona Kampel, Barbara Kiesewetter, Ladislaia Wolff, Mouhammed Amir Habra, Vania Balderrama-Brondani, Won Gu Kim, Chae A. Kim, Christine Spitzweg, Viktoria Florentine Koehler, Merel Tessa Stegenga, Wouter T. Zandee, Thera P. Links, Ana Luiza Maia, Rafael Selbach Scheffel, Jason Sheehan, Matti L. Gild, Fabian Pitoia, Jan Jiskra, Rajeev Parameswaran, Ralf Paschke, Roman Liscak, Ali S. Alzahrani, Jonathan Wadsley, W. Edward Visser, Francesco Frasca, Pasqualino MalandrinoBackground:
Brain metastases (BMs) from nonanaplastic follicular cell–derived thyroid carcinoma (hereinafter referred to as non-ATC) are rare and not well characterized, with limited evidence guiding treatment and prognostic stratification. We aimed to describe clinical features, treatment patterns, and outcomes of patients with BMs from non-ATC and to develop and validate a disease-specific prognostic score.
Methods:
This retrospective international multicenter study included adults with histologically confirmed non-ATC and radiologically documented BMs treated at 19 tertiary referral centers. Clinical, radiological, treatment, and outcome data were collected. Independent predictors of progression-free survival (PFS) and overall survival (OS) were analyzed using Cox regression, and variables identified were used to develop a disease-specific Graded Prognostic Assessment (non-ATC GPA), exploratorily assessed in an independent SEER cohort.
Results:
A total of 189 patients were included; median age at BM diagnosis was 59 years (interquartile range [IQR] 48–67). First-line BM treatments included stereotactic radiosurgery (27.0%), neurosurgery (23.8%), whole-brain radiotherapy (18.5%), and best supportive care (10.6%). Median PFS was 7.0 months (IQR: 2.9–22.4), and median OS was 15.0 months (IQR: 4.0–38.4). Independent predictors of shorter OS were age >75 years, Eastern Cooperative Oncology Group performance status ≥2, papillary histology, extracranial metastases, and ≥4 BM. The GPA stratified patients into four prognostic groups with median OS ranging from 72.6 months in the highest-score group to 3.7 months in the lowest. An exploratory SEER-based assessment showed survival differences across adapted prognostic groups (
Conclusions:
BMs from non-ATC are associated with poor survival and marked prognostic heterogeneity. The proposed GPA may provide a useful framework for prognostic stratification, pending further validation in independent datasets to support individualized management.