Abstract

Objective: To assess the prognostic value of tumor-infiltrating lymphocytes (TILs) in triple-negative breast cancer (TNBC) by menopausal status.
Methodology: This retrospective cohort study included 442 TNBC patients treated at the University of Sulaimani from January 2015 to January 2025, including 275 premenopausal and 167 postmenopausal women. TILs were evaluated on hematoxylin and eosin-stained sections using International TILs Working Group criteria and classified as low, moderate, or high. Clinical, pathological, treatment, and survival data were analyzed using Cox regression.
Results: TIL levels were significantly associated with tumor grade (p≤0.001) but not with menopausal status. Patients with high TIL infiltration had a 63% lower risk of death than those with low or moderate infiltration (HR=0.37, HR=0.37, HR=0.37, 95% CI: 0.20–0.70, p=0.002, p=0.002, p=0.002).
Conclusion: Higher TIL levels predict better survival in TNBC regardless of menopausal status, supporting their role as a prognostic biomarker across both premenopausal and postmenopausal patients.

Key words: Triple-negative breast neoplasms, tumor-infiltrating lymphocytes, hormone negative.