AUTHOR=Zheng Yue , You Liting , Feng Baijie , Tang Min , Na Feifei 

TITLE=Cranial radiation therapy with hippocampus avoidance in lung cancer treatment: systematic review and meta-analysis

JOURNAL=Frontiers in Oncology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2023.1268754

DOI=10.3389/fonc.2023.1268754

ISSN=2234-943X

ABSTRACT=<sec><title>Background</title><p>The role of cranial radiation therapy with hippocampus avoidance (HA-CRT) in neurocognitive function (NCF), brain metastasis (BM), and overall survival (OS) in lung cancer remains unclear.</p></sec><sec><title>Methods</title><p>A meta-analysis was conducted to evaluate the impact of HA-CRT in lung cancer. Data from studies on hippocampal-avoidance prophylactic cranial irradiation (HA-PCI) and whole brain radiotherapy (HA-WBRT) were pooled.</p></sec><sec><title>Results</title><p>A total of 14 studies, including 5 randomized controlled trials, were included. The focus of NCF was mainly <italic>via</italic> the Hopkins Verbal Learning Test—Revised or the Free and Cued Selective Reminding Test. At 6 months post-radiotherapy, the pooled proportion of participants with decline in the performance of total recall, delayed recall, and discrimination in neurocognitive tests were 0.22 (95% CI 0.15, 0.29), 0.20 (95% CI 0.13, 0.27), and 0.14 (95% CI 0.05, 0.24) respectively. After 12 months, the proportion were 0.16 (95% CI 0.08, 0.23), 0.10 (95% CI 0.04, 0.16), and 0.04 (95% CI 0, 0.09) respectively. For HA zone relapse, the RR of HA-CRT versus CRT was 2.72 (95% CI 0.53, 13.87), and for 2-year BM, it was 1.20 (95% CI 0.82, 1.75). Regarding HA-PCI in SCLC, the 1-year BM rate was 0.12 (95% CI 0.07, 0.17), and the 2-year BM rate was 0.20 (95% CI 0.16, 0.25). For HA-WBRT in NSCLC with BM, the 2-year intracranial progression rate was 0.38 (95% CI 0.13, 0.62). There was no significant difference in OS between HA-CRT and CRT.</p></sec><sec><title>Conclusions</title><p>HA-CRT appears to be safe in lung cancer, but it may not outperform conventional CRT. Larger RCTs comparing HA-CRT and CRT are warranted.</p></sec><sec><title>Systematic review registration</title><p><uri xlink:href="https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022360890" xmlns:xlink="http://www.w3.org/1999/xlink">https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022360890</uri>, identifier CRD42022360890.</p></sec>