Tertiary lymphoid structures in tongue cancer: Association with clinicopathological parameters, preoperative S-1 chemotherapy response, and prognosis

Background

Tertiary lymphoid structures (TLSs) are observed in cancer-invasive sites of various organs, and show evidence of tumor-specific B and/or T cells, suggesting an active humoral antitumor response. The aim of this study was to evaluate the relationship between TLSs and prognosis in patients with tongue squamous cell carcinoma (TSCC) after preoperative S-1 chemotherapy.

Methods

Among 196 TSCC cases, 111 patients who received preoperative S-1 chemotherapy were compared to 85 patients who did not receive chemotherapy. We investigated the incidence of TLSs in both preoperative biopsy and resected specimens.

Results

TLSs were present in 24 (12%) biopsy specimens and 31 (16%) resected specimens. TLSs were associated with clinicopathologically advanced cases and positivity for lymphatic invasion. None of the cases with pStage 0 (i.e., noninvasive cancer) showed TLSs. In preoperative S-1 chemotherapy cases, TLSs were significantly more common in those treated with S-1 for more than 21 days and in those with treatment effects 0, Ia, and Ib. TLSs may not be a favorable prognostic factor by themselves but maybe a prognostic factor when combined with preoperative S-1 treatment.

Conclusion

The presence of TLSs was suggested to be a factor indicating a favorable prognosis when considering the indication for preoperative S-1 chemotherapy. The synergistic effect of S-1 by activating antitumor immunity may be associated with a better prognosis in TSCC patients with TLSs.