Tumor infiltrating lymphocytes (TILs) has been highlighted as a reliable prognostic and predictive biomarker in patients with triple negative breast cancer (TNBC). However, there has been lack of data investigating its significance in curatively resected, early-stage TNBC without adjuvant chemotherapy.
We retrospectively collected patients with TNBC regardless of the stage and histologic subtype, who underwent curative resection alone without adjuvant chemotherapy between 1999 to 2012 at Asan Medical Center (Seoul, Korea). In addition, we explored the clinical impact of TILs in subset of pathologically node-negative or small primary (≤1.0cm) tumors.
In a total of 78 patients, 71.8% were pathologically stage I, but nodal involvements were found in 12.8%. The reasons of no adjuvant chemotherapy were mostly patients’ refusal (73.1%) followed by physician’s discretion. All patients were available with TILs in surgical specimens with their median value of 26% (range, 1 to 90). During the median follow-up period of 74 months (range, 67 to 81), 21 patients (26.9%) experienced relapse, and 8 (10.3%) died of breast cancer progression. In relapsed patients, local relapse only was found in 14 patients (17.9%), whereas 7 (9.0%) accompanied distant metastases. Interestingly, TILs≤10% was significantly associated with distant metastasis at relapse (p = 0.050). Relapse with distant metastasis, pathological nodal positivity, and lower TILs were significantly correlated with inferior DSS (p
TILs might be a potential prognostic marker for early-stage TNBC who treated with curative resection alone, particularly in node negative or small primary TNBC. In these subsets, patients with TILs ≤10% may benefit from adjuvant chemotherapy.
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All authors have declared no conflicts of interest.