Grading and prognostic implications of tertiary lymphoid structures and CD155 expression in invasive breast carcinoma

Objective This study investigated the distribution and maturity of tertiary lymphoid structures (TLS) in invasive breast carcinoma tissue, as well as their prognostic value for postoperative recurrence. Methods This study retrospectively collected tissue samples from 127 patients with invasive breast carcinoma at the Second People’s Hospital of Guangdong Province between January 2021 and December 2023. Immunohistochemistry was conducted to measure TLS and the expression of related proteins in invasive breast carcinoma and peritumoral tissues. Univariate and multivariate analyses were performed to determine the association between TLS and postoperative recurrence during the follow-up period. Receiver operating characteristic (ROC) curves were constructed to evaluate the discriminatory performance of TLS for postoperative recurrence. Results The number and grade of TLS in invasive breast carcinoma tissue, as well as CD155 and Ki-67 expression, were markedly higher than those in peritumoral tissue. Compared with the non-recurrence group, patients in the recurrence group had a decreased number and grade of TLS in their tumor tissue and exhibited higher CD155 and Ki-67 expression intensity. Multivariate logistic regression analysis revealed that breast-conserving surgery, high CD155 expression, and high Ki-67 expression were independent positive predictors of postoperative recurrence, whereas a higher TLS grade was an independent negative predictor. TLS grade demonstrated moderate discriminatory performance, with an area under the ROC curve of 0.740, a sensitivity of 91.30%, and a specificity of 56.70%. Conclusion TLS presence in invasive breast carcinoma tissue and its maturity level are negatively associated with recurrence risk, serving as a potential prognostic marker for recurrence in patients with invasive breast carcinoma.