Abstract : Stromal tumor-infiltrating lymphocytes (sTILs) are an established prognostic biomarker in triple-negative breast cancer (TNBC), but the differential roles of CD8+ and CD4+ T-cell subsets remain unclear, particularly in early-stage disease. We evaluated the prognostic value of sTILs and T-cell subsets in TNBC patients treated with adjuvant chemotherapy. This prospective cohort study analyzed 109 stage I–III TNBC patients treated with surgery and adjuvant anthracycline-taxane chemotherapy at Lattakia University Hospital, Syria. Stromal TILs were quantified on hematoxylin–eosin slides using international guidelines. CD8+ and CD4+ T-cells were assessed via immunohistochemistry (anti-CD8/SP57, anti-CD4/SP35). Associations with 3-year recurrence-free survival (RFS) were analyzed using Kaplan-Meier estimates and Cox regression. High sTILs (≥ 30%) were observed in 59.6% of patients and correlated with younger age (P=0.009), smaller tumor size (P = 0.026), node-negative disease (P = 0.017), and higher histologic grade (P = 0.037). Patients with high sTILs had significantly better 3-year RFS (72.3% vs. 40.9%, P = 0.002). Elevated CD8+ T-cell density was independently associated with reduced recurrence (adjusted HR: 3.12, 95% CI: 1.8–5.4; P < 0.001), while CD4+ T-cells showed no prognostic significance (P = 0.41). Beyond sTILs, CD8+ T-cell infiltration enhances prognostic stratification in early-stage TNBC. Integrating CD8+ density into clinical assessments may improve risk prediction and guide therapeutic decisions.