Zone Formation of Lymphocyte Infiltration at Invasive Front as a Biomarker of Prognosis in Endometrial Carcinomas

OBJECTIVE: The clinical significance of lymphocyte infiltration (LI) at the invasive front in endometrial carcinomas (EC) has not been determined. The aim of the current study was to evaluate the association between zone formation of LI at the invasive front of the tumor margin and prognoses of the patients with EC. METHODS: All available pathological slides of the enrolled cases were reviewed, and the degree of LI at the invasive front was categorized into 2 groups: strong LI and weak LI. Clinical significance of LI was evaluated retrospectively. RESULTS: A total of 333 cases with EC were enrolled in the study: 225 cases with weak LI and 108 cases with strong LI. Weak LI was more frequently observed in the patients with grade1/2 endometrioid EC. Multivariate analyses for progression-free survival (PFS) and overall survival (OS) revealed that weak LI was identified as an independent worse prognostic factor for OS (p = 0.004) in addition to PFS (p = 0.022). CONCLUSION: Weak LI at the invasive front of the tumor margin was associated with worse prognoses in EC. Although further studies are needed, it is suggested that LI could be a biomarker of prognoses in EC.