Abstract 435P
Background
Gastric cancer (GC) is the fifth most common malignancy and the fourth main cause of cancer deaths globally. Brain metastases (BM), a rare occurrence of less than 1%, are often defined as a late gastric cancer manifestation that affects prognosis. The incidence, risk factors, and outcomes of gastric cancer BM are inconsistently reported in the literature.
Methods
A comprehensive search was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO registration number: CRD42021256696). We searched Medline, Web of Science and Scopus databases for observational or randomized controlled studies on gastric cancer patients with brain metastases until August 2023. All relevant studies had a high quality, according to Newcastle-Ottawa Quality Assessment Scale.
Results
Eighteen articles were selected reporting the findings of 17 retrospective investigations and one prospective study, which included a total of 70,237 GC patients, 621 of whom were diagnosed with BM. The average incidence of BM in GC patients was 2.29% (95% CI 1.06-3.53), ranging from 0.47% to 7.79%, as reported in 12 studies. The majority of neurological symptoms documented in six studies were headaches (mean 37%, range 18%-57%). Analysing the two studies that reported on HER2 status, there was a statistically significant difference regarding BM between patients with positive and negative HER2 status, with an odds ratio of 43.24 (95% CI 2.05-913.39; p-value=0.02). The mean time from the diagnosis of GC to the diagnosis of BM was 11.44 months. The mean OS time from GC diagnosis in the 18 patients with CNS metastases was 14.2 months. Based on the random-effects model, the pooled mean difference (MD) was 12.39 (95% CI 2.03-22.75), with statistically better OS for patients who underwent surgical resection of BM than those without resection (p-value=0.02).
Conclusions
The results indicate that gastric cancer patients who underwent surgery for BM have a higher survival rate. Also, patients with HER2-positive GC have a higher incidence of brain metastases.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.