Hypofractionated adjuvant surgical cavity radiotherapy following resection of limited brain metastasis

• Published in: Journal of clinical neuroscience 2020-12, Vol.82 (Pt A), p.155-161
• Main Authors: Wijetunga, A., Jayamanne, D., Cook, R., Parkinson, J., Little, N., Curtis, J., Brown, C., Back, M.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Brain; Brain Neoplasms - radiotherapy; Brain Neoplasms - surgery; Cohort Studies; Disease Progression; Female; Humans; Magnetic Resonance Imaging; Male; Metastasis; Middle Aged; Neoplasm; Neoplasm Recurrence, Local - radiotherapy; Neoplasm Recurrence, Local - surgery; Radiation Dose Hypofractionation; Radiation therapy; Radiosurgery; Radiotherapy, Intensity-Modulated; Recurrence; Retrospective Studies; Survival; Targeted radiotherapy
• ISSN: 0967-5868; 1532-2653
• DOI: 10.1016/j.jocn.2020.10.041

•The brain is a major site of primary tumour metastasis, especially from the lung.•Limited metastases are typically treated with surgery and adjuvant radiotherapy.•WBRT reduces failure rates, but incurs significant neurological toxicity.•Fractionated radiotherapy leads to non-inferior survival and control.•Rates of radionecrosis are lower with a focal fractionated approach. Following surgical resection of oligometastatic disease to the brain there is a high rate of local relapse which is reduced by the addition of focal radiation therapy, often delivered as single fraction stereotactic radiosurgery (SRS) to the surgical cavity. This study audited the outcomes of an alternative approach using hypofractionated radiation therapy (HFRT) to the surgical resection cavity. Seventy-nine patients who received surgical resection and focal radiation therapy to the surgical cavity using HFRT with intensity modulated radiation therapy with or without stereotactic radiotherapy were identified. Doses were delivered in five fractions every second day for 10 days. Follow-up involved MRI surveillance with three-monthly MRI scans post resection. The major endpoints were local control at the surgical cavity site, and presence of radiation necrosis at the treated site. Seventy-nine patients were included for the analysis with a median follow-up of 10.8 months. Of the cohort, 56% experienced intracranial progression, with all patients progressing distant to the resection cavity, and 7% progressing locally in addition. The one-year local control rate was 89.8%. The median progression-free survival was 10.0 months and median overall survival was 14.3 months. There was one CTCAE grade 3 toxicity of symptomatic radiation necrosis with no grade 4–5 toxicities seen. The rate of local relapse following HFRT to the surgical cavity is low with minimal risk of radiation necrosis. HFRT can be considered as an alternative to SRS for focal radiotherapy after brain metastasis resection.