Clinical significance of signet ring cells in surgical esophageal and esophagogastric junction adenocarcinoma: A systematic review and meta-analysis

Abstract

BACKGROUND The clinical significance of signet ring cells (SRCs) in surgical esophageal and esophagogastric junction adenocarcinoma (EEGJA) remains unclear now. AIM To explore the association between the presence of SRCs and the clinicopathological and prognostic characteristics in surgical EEGJA patients by combining and analyzing relevant studies. METHODS The PubMed, Web of Science, and EMBASE electronic databases were searched for the relevant literature up to March 28, 2021. The relative risk (RR) with 95% confidence interval (CI) was calculated to assess the relationship between SRCs and clinicopathological parameters of surgical EEGJA patients, and the hazard ratio (HR) with 95%CI was calculated to explore the impact of SRC on the prognosis. All statistical analyses were conducted with STATA 12.0 software. RESULTS A total of ten articles were included, involving 30322 EEGJA patients. The pooled results indicated that the presence of SRCs was significantly associated with tumor location (RR: 0.76, 95%CI: 0.61-0.96, P = 0.022; I 2 = 49.4%, P = 0.160) and tumor-node-metastasis stage (RR: 1.30, 95%CI: 1.02-1.65, P = 0.031; I 2 = 73.1%, P = 0.002). Meanwhile, the presence of SRCs in surgical EEGJA patients predicted a poor overall survival (HR: 1.36, 95%CI: 1.12-1.65, P = 0.002; I 2 = 85.7%, P < 0.001) and disease-specific survival (HR: 1.86, 95%CI: 1.55-2.25, P < 0.001; I 2 = 63.1%, P = 0.043). CONCLUSION The presence of SRCs is related with advanced tumor stage and poor prognosis and could serve as a reliable and effective parameter for the prediction of postoperative survival and formulation of therapy strategy in EEGJA patients. However, more high-quality studies are still needed to verify the above findings.