J Neurooncol. 2026 Feb 13;176(3):210. doi: 10.1007/s11060-025-05366-6.
ABSTRACT
PURPOSE: Brain tumors, characterized by the uncontrolled proliferation of abnormal cells within cerebral tissue, remain clinically challenging entities. Radiotherapy and chemotherapy constitute fundamental therapeutic modalities; however, their effects on healthy brain structures are not fully understood. This study aimed to evaluate the impact of these treatments on volumetric changes in brain structures and tumor size in patients with primary or metastatic brain tumors.
METHODS: A retrospective cohort of 47 patients aged 18-90 years treated at Inonu University Turgut Özal Medical Center between 2012 and 2023 was analyzed. Brain MRI scans were evaluated at three time points: pre-treatment, post-radiotherapy, and post-chemotherapy. Radiotherapy was delivered at a median dose of 60 Gy in 30-33 fractions, and temozolomide was used as the chemotherapy agent. Volumetric measurements of the telencephalon, diencephalon, ventricles, white matter, brainstem, cerebellum, and cerebral cortex were performed using MRICloud, while tumor volumes were quantified using the VolBrain platform. All volumetric differences were statistically tested using repeated-measures ANOVA with corresponding p-values reported.
RESULTS: A statistically significant increase in telencephalon volume was observed after radiotherapy, followed by a return toward baseline measurements after chemotherapy. The diencephalon demonstrated a significant and persistent volume reduction following radiotherapy (p < 0.05). No statistically significant volumetric changes were identified in the ventricles, white matter, brainstem, cerebellum, or cerebral cortex (p > 0.05). Tumor volume changes were also statistically evaluated and showed no significant differences across the three time points (p = 0.456), indicating stable disease during the treatment course.
CONCLUSION: Radiotherapy and chemotherapy lead to region-specific volumetric alterations in the brain. The transient telencephalon enlargement is more likely attributable to treatment-related edema or inflammatory processes rather than functional improvement. The persistent diencephalon volume decline may reflect early treatment-related tissue vulnerability. Incorporating automated volumetric assessment into routine follow-up may support early detection of therapy-related structural changes and facilitate more personalized treatment planning.
PMID:41686371 | DOI:10.1007/s11060-025-05366-6
