IMPAKT 2017: Tumor-Infiltrating Lymphocyte Levels in HER2-Positive Breast Cancer
At the recent IMPAKT Breast Cancer Conference in Brussels, Belgium, Solinas et al presented findings suggesting that baseline levels of tumor-infiltrating lymphocytes (TILs) have a strong prognostic effect in patients with HER2-positive breast cancer, with higher levels of TILs being linked to an increased benefit from neoadjuvant chemotherapy plus anti-HER2 agents. These results are based on a meta-analysis of published data from five large clinical trials (Abstract 27P).
A total of 1,256 patients participated in the following neoadjuvant trials: CherLOB, GeparQuattro, GeparQuinto, GeparSixto, and NeoALTTO. Evaluation of the data from these studies showed a significant association between pathologic complete response rates and high pretreatment levels of TILs. In addition, no interaction was seen between high and non-high TIL subgroups in terms of response to anti-HER2 agents (trastuzumab vs lapatinib vs trastuzumab/lapatinib) or between regimens containing anthracyclines plus taxanes vs taxanes alone. In the 869 patients participating in the CherLOB, GeparQuattro, GeparQuinto, and GeparSixto trials, the association between pathologic complete response and high level of TILs was higher.