上皮内 TIL（肿瘤浸润淋巴细胞）密度及其密度异质性联合作为 III 期结直肠癌预后标志物的价值

Tumor-infiltrating lymphocyte (TIL) density is both a prognostic and a predictive factor in colorectal cancer (CRC). Whether the heterogeneity of TIL density across the tumor plays an important role in the clinical outcome of CRC is not well known. Adjuvant chemotherapy-treated patients with stage III CRC were analyzed for survival according to TIL density and density heterogeneity, which were determined on CD8-immunostained slides using a machine learning method and by calculating the Simpson evenness index, respectively.

High heterogeneity of the intraepithelial TIL density was found to be an independent prognostic factor, with a hazard ratio of 1. 970 (1. 207-3. 215) in the multivariate analysis of recurrence-free survival. High heterogeneity was closely associated with a high T category, venous invasion, perineural invasion, and KRAS mutation.

The combination of both intraepithelial TIL density and density heterogeneity was significantly associated with the prognosis of patients: low TIL density/high TIL heterogeneity showed hazard ratios of 3. 284 (1. 639-6. 578) and 4. 176 (1. 713-10. 178) in the discovery and validation cohorts, respectively.

Our findings suggest that the heterogeneity status of intraepithelial TIL density might help delineate patients with better vs. worse survival when combined with intraepithelial TIL density.