196P - Clinical significance of circulating CD8+ and CD4+ T cell proliferation in advanced gastric cancer receiving first-line chemotherapy

Background

We sought to explore whether the circulating proliferative T lymphocyte subtypes in patients with advanced gastric cancer (AGC) can be used as an indicator of prognosis.

Methods

Blood samples were collected from patients with AGC before treatment and analyzed by fluorescence-activated cell sorting analysis. Patients were divided into two groups based on the ratio of CD8+ T cells to CD4+ T cells and the ratio of CD8+ T cells to CD4+ T cells within Ki-67+ T cells. Survival between the groups was compared using the Kaplan-Meier method and the log-rank test. Multivariate analyses were also performed.

Results

A total of 92 patients enrolled in the study. The median age was 64.2 years, and the male-to-female ratio was 2.3:1. The median survival duration was 12.5 months. No significant differences in progression-free survival (PFS) and overall survival (OS) were observed between the groups with high and low CD8/CD4 ratios. However, the group with a high ratio of CD8/CD4 within proliferating T cells (n = 46) had a significantly longer OS (16.8 months vs. 11.3 months; p = 0.011) compared to the group with a low ratio of CD8/CD4 within proliferating T cells (n = 46). PFS did not vary between these proliferating CD8/CD4 ratio groups. A multivariate analysis indicated that the ratio of proliferating CD8 to CD4 was an independent prognostic factor for OS.

Conclusions

A high CD8/CD4 ratio among proliferating T cells in circulation could be associated with a better prognosis in patients with AGC receiving first-line chemotherapy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.