The prognostic significance of the absolute counts of peripheral blood lymphocyte subsets in patients with advanced gastric cancer

Abstract

Abstract The percentages of lymphocyte subsets (PL) of peripheral blood which mainly include CD3+, CD3+CD4+, CD3+CD8+, B, and NK cells have been paid much attention in advanced gastric cancer (AGC), but PL is often inconsistent with disease severity and tumor progression, appear no significant changes even after chemotherapy, which often lead to clinical misjudgment. Clinic observation suggests that absolute counts of lymphocyte subsets (ACL) are more correlated to the tumor progression and prognosis. The 291 patients with AGC including 93 who received chemotherapy and 63 normal controls (NCs) were recruited from the First Teaching Hospital of Tianjin University of Traditional Chinese Medicine. The PL and ACL of peripheral blood were detected by flow cytometry-based single-platform method. PL and ACL between AGC patients (AGCs) and NCs were compared. The primary endpoint was progression-free survival (PFS) and overall survival (OS), the second endpoint was complete response (CR), partial response (PR), stable disease (SD), Disease Control rate, and progressive disease (PD). Two independent t-tests were used to compare between groups. PFS was calculated by the Kaplan-Meier method. Univariate and multivariate analyses were used to analyze the variables that affect disease progression. Compared to NCs, the percentages of CD3+CD8+ and B cells were decreased only (P < 0.05), while the AC of CD3+, CD3+CD4+, CD3+CD8+, B and NK cells were significantly lower (P < 0.001). AGCs with high ACL had longer PFS and OS than those with low ACL (P < 0.0001). Multivariate analysis showed that when the AC of CD3+CD4+ cells was more than 405 cells/μL, the PFS and OS of AGCs were significantly prolonged (P < 0.001), and the sensitivity and specificity were the most obvious. This study evaluated the prognosis of 93 AGCs received chemotherapy: the high ACL had significantly longer PFS and OS compared with low groups (P < 0.0001), excepted AC of NK cells in PFS; the AC of CD3+CD4+ > 405 cells/μL was an independent protective factor for PFS and OS in AGCs (P < 0.001); all ACL have greater disease control rate (DCR) than progressive disease (PD) rate at high ACL, in contrast to low ACL where PD rate is higher than DCR. The ACL was significantly impaired and closely associated with PFS and OS in AGCs, the same was true in patients receiving chemotherapy. Statistics suggested the AC of CD3+CD4+ cells was the most sensitive parameter for the prognosis of AGCs. Chinese Clinic Trial Registry number: ChiCTR-IOR-17014139; Registry date: 2017/12/25.