Using TIL Score to Predict Overall Survival, Guide Trastuzumab De-Escalation Among Patients With HER2-Negative Early Breast Cancer
According to updated analysis results from the ShortHER trial, tumor-infiltrating lymphocyte (TIL) score is predictive of overall survival (OS) and can potentially guide trastuzumab de-escalation among patients with human epidermal growth factor receptor 2 (HER2)-negative early breast cancer.
These results were first presented by Maria Vittoria Dieci, MD, University of Padua, Italy, at the 2024 European Society for Medical Oncology (ESMO) Congress in Barcelona, Spain.
In this study, 1254 patients with HER2-positive early breast cancer were randomized to receive adjuvant trastuzumab plus chemotherapy for a duration of either 9 weeks or 1 year. Researchers scored TILs based on centralized primary tumor location and found scores of < 20 (n = 672), ≥ 20 (n = 194), < 30 (n = 735), ≥ 30 (n = 131), < 50 (n = 799), ≥ 50 (n = 67). The primary end points were 10-year distant disease-free survival (DDFS) and OS rates.
At a median follow-up of approximately 9 years, there were 107 DDFS events and 74 OS events. DDFS rate was 85% for patients < 20, 89.8% (P = .11) for patients ≥ 20, 84.9% for patients < 30, 91.7% (P = .008) for patients ≥ 30, 84.9% for patients < 50, and 96.9% (P = .17) for patients ≥ 50. OS was 89.3%, 91.3% (P = .85), 89%, 93.3% (P = .32), 88.8%, and 98.1% (P = .34), respectively.
“This is the first demonstration of an independent prognostic role of TILs in terms of OS for [HER2-positive early breast cancer patients] treated with adjuvant [chemotherapy] and anti-HER2,” concluded Dr Dieci. “These data further support the inclusion of immune biomarkers into prognostic tools.”
Source:
Bisagni G, Bartolini S, Schirone A, et al. TILs and overall survival (OS) in HER2+ early breast cancer (eBC): 10-year (yr) updated analysis of the ShortHER trial. Presented at 2024 ESMO Congress. September 13-17, 2024. Abstract 239MO
