Maturation of tertiary lymphoid structures and recurrence of stage II and III colorectal cancer

Abstract

Tertiary lymphoid structures (TLS) are associated with favorable outcome in non-metastatic colorectal carcinoma (nmCRC), but the dynamics of TLS maturation and its association with effective anti-tumor immune surveillance in nmCRC are unclear. Here, we hypothesized that not only the number of TLS but also their composition harbors information on recurrence risk in nmCRC. In a comprehensive molecular, tissue, laboratory, and clinical analysis of 109 patients with stage II/III nmCRC, we assessed TLS numbers and degree of maturation in surgical specimens by multi-parameter immunofluorescence of follicular dendritic cell (FDC) and germinal center (GC) markers. TLS formed in most tumors and were significantly more prevalent in highly-microsatellite-instable (MSI-H) and/or BRAF-mutant nmCRC. We could distinguish three sequential TLS maturation stages which were characterized by increasing prevalence of FDCs and mature B-cells: [1] Early TLS, composed of dense lymphocytic aggregates without FDCs, [2] Primary follicle-like TLS, having FDCs but no GC reaction, and [3] Secondary follicle-like TLS, having an active GC reaction. A simple integrated TLS immunoscore reflecting these parameters identified a large subgroup of nmCRC patients with a very low risk of recurrence independently of clinical co-variables such as ECOG performance status, age, stage, and adjuvant chemotherapy. We conclude that (1) mismatch repair and BRAF mutation status are associated with the formation of TLS in nmCRC, (2) TLS formation in nmCRC follows sequential maturation steps, culminating in germinal center formation, and (3) this maturation process harbors important prognostic information on the risk of disease recurrence.

Helper T cell-dominant tertiary lymphoid structures are associated with disease relapse of advanced colorectal cancer

“…Since there is no established TLS classification, previous studies adopted their own classifications. 12,25,26 One previous report of ovarian cancer classified lymphoid aggregates into four types based on size, cellular composition, and degree of GC organization. 25 The authors examined the associations between the four types and tumor infiltrating lymphocytes (TILs) and plasma cell densities, whereas they did not mention the relationships of the four types to clinical outcomes.…”

“…Most previous studies have consistently showed a positive correlation between higher TLS densities and better prognosis in different cancers.. [6][7][8][9] On the other hand, some reports of biliary tract cancer and of some populations with CRC showed that high numbers of TLSs or lymphoid aggregates had no impact on patients' prognosis. [10][11][12] Among them, a correlation between the number of TLSs and patients' prognosis was reported when limited to cases with stage II CRC, or TLSs with follicular structure were examined. There are two possible explanations for the discrepancy in the results.…”

“…A previous study of stage II and III CRC reported that TLS density did not correlate with disease relapse, but in the case of TLSs with an FDC network or GC formation, a significant association was present. 12 Moreover, an increasing number of studies have shown positive correlations between good and poor clinical outcomes and different cellular components of TLSs, such as DCs, T cells, B cells, follicular helper T cells (Tfh), regulatory T cells (Tregs), HEVs, and chemokines. 4 In CRC, increased CD3 + T cell infiltration of TLSs or Tfh-related gene expressions, such as CXCL13 and IL-21, have been reported to predict improved survival.…”

TGF-β induced CXCL13 in CD8+ T cells is associated with tertiary lymphoid structures in cancer

“…Conflicting reports exist on the link between neo-antigen load and the presence of tertiary lymphoid structures (TLS) 16,25 . Therefore, we first assessed whether tumors with a high mutational load were enriched for TLS-associated genes in mRNA sequencing data from The Cancer Genome Atlas (TCGA).…”

Tumor-associated tertiary lymphoid structure predicts postoperative outcomes in patients with primary gastrointestinal stromal tumors

“…47,53,54 In patients with stage II/III non-metastatic colorectal carcinoma (nmCRC), TLS has been shown to be significantly associated with highmicrosatellite-instability (MSI-H) and BRAF-mutant nmCRC, which may be through the production of immunogenic epitopes. 55 The presence of gene mutations is an important characteristic associated with GIST patients. We analyzed the combinational effects of these mutations and TLS in clinical outcomes.…”