The prognostic value of stromal tumor-infiltrating lymphocytes in intrahepatic cholangiocarcinoma: a population-based study

Objective We assess the predictive value impacted by tumor-infiltrating lymphocytes (TILs) for overall survival (OS) and progression-free survival (PFS) in patients with intrahepatic cholangiocarcinoma (ICC) undergoing complete resection. Methods Sixty-eight patients with resectable ICC were included in this study. We studied stromal TIL density and scored it by staining sections from surgically resected ICC patients with hematoxylin and eosin (HE). The clinical data and prognosis of patients with ICC were obtained by searching clinical and follow-up records. Results A stromal TIL negative status was a predictor of poor OS (HR = 0.41, 95% CI 0.20-0.83, p = .01) and poor PFS (HR = 0.47, 95% CI 0.23-0.97, p = .04) independently. Low stromal TIL density was associated with high levels of CA125 (p = .03) and CA19-9 (p < .01). The high level of CA19-9 (p = .05), high differentiation (p = .02), a large diameter (p = .05), a positive bile duct/vascular cancer embolus (p = .03) and positive satellite nodules (p = .02) were tendencies to develop tumors for patients with a negative status of stromal TIL. Conclusion Our data prompt for the prediction of the PFS and OS of patients with ICC after complete resection, stromal TILs play an important role.