Abstract 26P
Background
In patients with triple-negative breast cancer (TNBC) undergoing neoadjuvant chemotherapy (NACT), higher tumor-infiltrating lymphocytes (TILs) strongly correlate with increased rates of pathologic complete response (pCR) and improved survival. The aim of the present work is to investigate the changes of TIL levels from baseline biopsy to residual disease (RD) in TNBC patients failing to achieve pCR after standard NACT with anthracycline-taxane (A-T) +/- carboplatin (Cb).
Methods
TNBC (ER&PgR<10%) patients treated with neoadjuvant A-T +/-Cb failing to achieve pCR were included. Stromal TILs were evaluated on baseline biopsy and matched samples of RD. The non-parametric Wilcoxon test was applied to compare TIL levels from baseline biopsy to RD.
Results
79 patients with matched samples of baseline TILs and RD-TILs were included: 62% treated with A-T, 38% with A-TCb. Mean and median baseline TILs were 8.8% and 5%; mean and median RD-TILs were 14.1% and 8%. The distribution of TIL categories in matched samples of baseline biopsy and RD is shown in the table. RD-TILs were significantly higher than baseline TILs in the overall population (p=0.004) and in both A-T (p=0.027) and A-TCb subgroups (p=0.043). A significant increase of TIL levels after NACT was also seen in patients with low baseline TILs, in the overall population (p<001) and in both treatment subgroups (A-T, p=0.002, A-TCb, p=001). Table: 26P
| RD | ||||
| Low TILs (%) | Intermediate TILs (%) | High TILs (%) | ||
| Baseline | Low TILs (%) | 45 (57) | 15 (19) | 2 (2.5) |
| Intermediate TILs (%) | 6 (7.6) | 10 (12.7) | 1 (1.3) | |
| High TILs (%) | 0 | 0 | 0 |
TILs categories have been classified according to cutoffs suggested by Denkert et al, 2018 (low: 0-10; intermediate: 11-59; high: ≥60).
Conclusions
We reported in a population of TNBC patients failing to achieve pCR after standard NACT, that A-T +/- Cb is capable of enhancing tumor immune infiltration from pre-treatment tumor to RD. Importantly, we observed that TIL infiltration was enhanced after A-T +/- Cb also in patients with “immune-cold” tumors at baseline.
Legal entity responsible for the study
The authors.
Funding
Univ.
Disclosure
F. Miglietta: Financial Interests, Personal, Invited Speaker, outside the submitted work: Roche. G. Griguolo: Financial Interests, Personal, Invited Speaker: Novartis; Financial Interests, Personal, Invited Speaker: Eli Lilly; Other, Travel Support: Novartis; Other, Travel Support: Amgen; Other, Travel Support: Pfizer; Other, Travel Support: Daiichi Sankyo. M. Fassan: Financial Interests, Personal, Advisory Board, outside the submitted work: Astellas Pharma; Financial Interests, Personal, Advisory Board, outside the submitted work: QED Therapeutics; Financial Interests, Personal, Advisory Board, outside the submitted work: Diaceutics; Financial Interests, Personal, Advisory Board, outside the submitted work: Tesaro; Financial Interests, Personal, Advisory Board, outside the submitted work: Roche; Financial Interests, Personal, Advisory Board, outside the submitted work: Eli Lilly; Financial Interests, Personal, Advisory Board, outside the submitted work: Novartis. C.A. Giorgi: Financial Interests, Personal, Invited Speaker, outside the submitted work: Novartis. V. Guarneri: Financial Interests, Personal, Advisory Board: Roche; Financial Interests, Personal, Invited Speaker: Eli Lilly; Financial Interests, Personal, Advisory Board: Eli Lilly; Financial Interests, Personal, Advisory Board: Novartis; Financial Interests, Personal, Invited Speaker: Novartis; Financial Interests, Personal, Advisory Board: MSD; Financial Interests, Personal, Advisory Board: Gilead; Financial Interests, Institutional, Invited Speaker: Eli Lilly; Financial Interests, Institutional, Invited Speaker: Roche; Financial Interests, Institutional, Invited Speaker: BMS; Financial Interests, Institutional, Invited Speaker: Novartis; Financial Interests, Institutional, Invited Speaker: AstraZeneca; Financial Interests, Institutional, Invited Speaker: MSD; Financial Interests, Institutional, Invited Speaker: Synton Biopharmaceuticals; Financial Interests, Institutional, Invited Speaker: Merck. M.V. Dieci: Financial Interests, Personal, Invited Speaker: Eli Lilly; Financial Interests, Personal, Advisory Board: Novartis; Financial Interests, Personal, Advisory Board: Eli Lilly; Financial Interests, Personal, Invited Speaker: Pfizer; Financial Interests, Personal, Advisory Board: Seagen; Financial Interests, Personal, Advisory Board: Exact Science; Financial Interests, Personal, Other, Consultancy: Pfizer; Financial Interests, Institutional, Research Grant: Veneto Institute of Oncology IOV-IRCCS; Financial Interests, Institutional, Research Grant: Italian Ministry of health; Financial Interests, Institutional, Research Grant: University of Padova. All other authors have declared no conflicts of interest.