Combining the guidelines and multiphoton imaging methods to improve the prognostic value of tumor‐infiltrating lymphocytes in breast cancer.

Multiphoton microscopy (MPM) was introduced to label‐freely obtain tumor‐infiltrating lymphocytes (TILs) images from a total of 611 patients, and the prognostic value of TILs in breast cancer was assessed by the MPM method (TILs‐MPM) and guidelines method proposed by the International Immuno‐Oncology Biomarker Working Group (TILs‐WG), respectively. Moreover, the clinical (CLI) model, TILs‐WG + TILs‐MPM model, and full model (CLI + TILs‐WG + TILs‐MPM) were developed to investigate the prognostic value of TILs. The results show that TILs‐WG performs better in estrogen receptor (ER)‐negative subgroup, and TILs‐MPM is comparable with TILs‐WG in the ER‐negative subgroup, but has the best performance in the ER‐positive subgroup. Furthermore, the TILs‐WG + TILs‐MPM model can significantly improve the prognostic power compared with the TILs‐WG model, and the full model has excellent performance, with high area under the curve (AUC) and hazard ratio (HR) in both ER‐positive, ER‐negative subgroups, and the complete cohort. Our results suggest that the combination of TILs‐WG with TILs‐MPM model can greatly improve the prognostic value of TILs. [ABSTRACT FROM AUTHOR]