Distinguishing Brain Metastasis Progression From Radiation Effects After Stereotactic Radiosurgery Using Longitudinal GRASP Dynamic Contrast-Enhanced MRI. Issue 3 (17th March 2023)

• Record Type: Journal Article
• Authors: Berger, Assaf; Lee, Matthew D.; Lotan, Eyal; Block, Kai Tobias; Fatterpekar, Girish; Kondziolka, Douglas
• Is Part Of: Neurosurgery. Volume 92:Issue 3(2023)
• Page Start: 497
• Page End: 506
• Publication Date: 2023-03-17
• Subjects: Brain metastases -- Radiation necrosis -- Stereotactic radiosurgery -- MRI; Nervous system -- Surgery -- Periodicals; 617.48005
• DOI: 10.1227/neu.0000000000002228
• Languages: English
• ISSNs: 0148-396X

Abstract

Abstract : BACKGROUND: Differentiating brain metastasis progression from radiation effects or radiation necrosis (RN) remains challenging. Golden-angle radial sparse parallel (GRASP) dynamic contrast-enhanced MRI provides high spatial and temporal resolution to analyze tissue enhancement, which may differ between tumor progression (TP) and RN. OBJECTIVE: To investigate the utility of longitudinal GRASP MRI in distinguishing TP from RN after gamma knife stereotactic radiosurgery (SRS). METHODS: We retrospectively evaluated 48 patients with brain metastasis managed with SRS at our institution from 2013 to 2020 who had GRASP MRI before and at least once after SRS. TP (n = 16) was pathologically confirmed. RN (n = 16) was diagnosed on either resected tissue without evidence of tumor or on lesion resolution on follow-up. As a reference, we included a separate group of patients with non–small-cell lung cancer that showed favorable response with tumor control and without RN on subsequent imaging (n = 16). Mean contrast washin and washout slopes normalized to the superior sagittal sinus were compared between groups. Receiver operating characteristic analysis was performed to determine diagnostic performance. RESULTS: After SRS, progression showed a significantly steeper washin slope than RN on all 3 follow-up scans (scan 1: 0.29 ± 0.16 vs 0.18 ± 0.08, P = .021; scan 2: 0.35 ± 0.19 vs 0.18 ± 0.09, P = .004; scan 3: 0.32 ± 0.12 vs 0.17 ± 0.07, P = .002). No significant differences were found in the post-SRS washout slope. Post-SRS washin slope differentiated progression and RN with an area under the curve (AUC) of 0.74, a sensitivity of 75%, and a specificity of 69% on scan 1; an AUC of 0.85, a sensitivity of 92%, and a specificity of 69% on scan 2; and an AUC of 0.87, a sensitivity of 63%, and a specificity of 100% on scan 3. CONCLUSION: Longitudinal GRASP MRI may help to differentiate metastasis progression from RN.