Tertiary lymphoid structures (TLSs) have been proven to be predictive biomarkers of favorable clinical outcomes and response to immunotherapies in several solid malignancies. Nevertheless, the effect of TLSs in patients with breast cancer (BC) remains controversial. The objective of the current study is to investigate the clinicopathological and prognostic significance of TLSs in BC. Given the unique difficulties for detecting and quantifying TLSs, a TLS-associated gene signature based on The Cancer Genome Atlas (TCGA) BC cohort was used to validate and supplement our results.
Electronic platforms (PubMed, Web of Science, EMBASE, the Cochrane Library, CNKI, and Wanfang) were searched systematically to identify relevant studies as of January 11, 2022. We calculated combined odds ratios (ORs) with 95% confidence intervals (CIs) to determine the relationship between clinicopathological parameters and TLSs. The pooled hazard ratios (HRs) and 95% CIs were also calculated to evaluate the prognostic significance of TLSs. The TLS signature based on the TCGA BC cohort was applied to validate and supplement our results.
Fifteen studies with 3,898 patients were eligible for enrollment in our study. The combined analysis indicated that the presence of TLSs was related to improved disease-free survival (DFS) (HR = 0.61, 95% CI: 0.41–0.90,
TLS presence provides new insight into the clinicopathological features and prognosis of patients with BC, whereas the factors discussed limited the evidence quality of this study. We look forward to consistent methods to define and characterize TLSs, and more high-quality prospective clinical trials designed to validate the value of TLSs alone or in combination with other markers.