Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2023 Jul;163(3):515-527.
doi: 10.1007/s11060-023-04384-6. Epub 2023 Jul 3.

Hippocampal avoidance in whole brain radiotherapy and prophylactic cranial irradiation: a systematic review and meta-analysis

Sandra Leskinen  1 , Harshal A Shah  2 , Beril Yaffe  3 , Shonna J Schneider  3 , Netanel Ben-Shalom  4 , John A Boockvar  4 , Randy S D'Amico  4 , A Gabriella Wernicke  5
Affiliations
Meta-Analysis

Hippocampal avoidance in whole brain radiotherapy and prophylactic cranial irradiation: a systematic review and meta-analysis

Sandra Leskinen et al. J Neurooncol. 2023 Jul.

Abstract

Purpose: We systematically reviewed the current landscape of hippocampal-avoidance radiotherapy, focusing specifically on rates of hippocampal tumor recurrence and changes in neurocognitive function.

Methods: PubMed was queried for studies involving hippocampal-avoidance radiation therapy and results were screened using PRISMA guidelines. Results were analyzed for median overall survival, progression-free survival, hippocampal relapse rates, and neurocognitive function testing.

Results: Of 3709 search results, 19 articles were included and a total of 1611 patients analyzed. Of these studies, 7 were randomized controlled trials, 4 prospective cohort studies, and 8 retrospective cohort studies. All studies evaluated hippocampal-avoidance whole brain radiation treatment (WBRT) and/or prophylactic cranial irradiation (PCI) in patients with brain metastases. Hippocampal relapse rates were low (overall effect size = 0.04; 95% confidence interval [0.03, 0.05]) and there was no significant difference in risk of relapse between the five studies that compared HA-WBRT/HA-PCI and WBRT/PCI groups (risk difference = 0.01; 95% confidence interval [- 0.02, 0.03]; p = 0.63). 11 out of 19 studies included neurocognitive function testing. Significant differences were reported in overall cognitive function and memory and verbal learning 3-24 months post-RT. Differences in executive function were reported by one study, Brown et al., at 4 months. No studies reported differences in verbal fluency, visual learning, concentration, processing speed, and psychomotor speed at any timepoint.

Conclusion: Current studies in HA-WBRT/HA-PCI showed low hippocampal relapse or metastasis rates. Significant differences in neurocognitive testing were most prominent in overall cognitive function, memory, and verbal learning. Studies were hampered by loss to follow-up.

Keywords: Brain tumor; Hippocampal avoidance; Hippocampus; Neurocognitive function; Organs at risk; Radiation.

PubMed Disclaimer

References

    1. Takahashi T et al (2017) Prophylactic cranial irradiation versus observation in patients with extensive-disease small-cell lung cancer: a multicentre, randomised, open-label, phase 3 trial. Lancet Oncol 18(5):663–671. https://doi.org/10.1016/S1470-2045(17)30230-9 - DOI - PubMed
    1. Lee YW et al (2012) Whole brain radiation-induced cognitive impairment: pathophysiological mechanisms and therapeutic targets. Biomol Ther (Seoul) 20(4):357–370. https://doi.org/10.4062/biomolther.2012.20.4.357 - DOI - PubMed
    1. Makale MT et al (2017) Mechanisms of radiotherapy-associated cognitive disability in patients with brain tumours. Nat Rev Neurol 13(1):52–64. https://doi.org/10.1038/nrneurol.2016.185 - DOI - PubMed
    1. Patchell RA et al (1998) Postoperative Radiotherapy in the treatment of single metastases to the brain: a Randomized Trial. JAMA 280(17):1485–1489. https://doi.org/10.1001/jama.280.17.1485 - DOI - PubMed
    1. DeAngelis LM, Delattre JY, Posner JB (1989) Radiation-induced dementia in patients cured of brain metastases. Neurology 39(6):789–796. https://doi.org/10.1212/wnl.39.6.789 - DOI - PubMed

MeSH terms

LinkOut - more resources