Stromal Tumor-infiltrating Lymphocytes in NRG Oncology/NSABP B-31 Adjuvant Trial for Early-stage HER2-positive Breast Cancer
Menée à partir de données portant sur 1 581 patientes atteintes d'un cancer du sein HER2+ de stade précoce, cette étude évalue l'association entre la présence de lymphocytes dans le stroma tumoral et la survie des patients, le bénéfice du trastuzumab ou la présence de mutations génétiques au niveau de la tumeur
We retrospectively assessed association of stromal tumor-infiltrating lymphocytes (sTILs) with clinical outcomes and molecular variables reportedly predictive of trastuzumab-benefit in NSABP B-31 (N = 2,130). sTILs were assessed in 1,581 eligible B-31 cases utilizing all available H&E slides. Mean concordance between main reviewer and six other pathologists was 90.8% in 100 cases. Cox regressions were used to calculate hazard ratios (HRs). In chemotherapy and trastuzumab-added-to-chemotherapy arms, increases in sTILs, as a semi-continuous variable (combined arms HR = 0.42, 95% [CI]=0.27 to 0.64, two-sided P < 0.001) or as lymphocyte-predominant breast cancer (BC) with >50% sTILs (combined arms HR = 0.65, 95% CI = 0.49-0.86, two-sided P = 0.003), were statistically significantly associated with improved disease-free survival. There was no association of sTILs with trastuzumab-benefit. However, higher sTILs were statistically significantly associated with higher-trastuzumab-benefit groups by 8-gene prediction model (two-sided P < 0.001). Neither PIK3CA mutations nor Fc-gamma-receptor polymorphisms were associated with sTILs. sTILs may have utility as a prognostic biomarker identifying HER2-positive early-BC at low recurrence risk.
Journal of the National Cancer Institute , résumé, 2018