KEY TAKEAWAYS
- The study aimed to investigate features and outcomes of HER2-negative and HER2-low MBC using real-world data.
- The results demonstrated that the HER2-low tumors were associated with improved survival compared to HER2-negative tumors in MBC.
Investigating real-world data, Zachary Neubauer and the team aimed to analyze characteristics and outcomes of HER2-negative and HER2-low metastatic breast cancers (MBC).
The National Cancer Database was utilized to identify MBC patients classified as HER2-low or HER2-negative via immunohistochemical staining. Demographic and clinical correlates of each subtype were identified through binomial regression analysis. Additionally, survival correlates were identified through Cox multivariable regression analysis (MVA) and propensity-match analysis.
After excluding missing data, 24,636 patients diagnosed with MBC between 2008 and 2015 were identified. Of these, 27.9% were HER2-negative, and 72.1% were HER2-low. No significant demographic differences were observed between the groups. HER2-low tumors were half as likely to exhibit concomitant hormone receptor-positive status (P < 0.01).
Among hormone receptor-negative patients, the 3-year survival rate was 33.8% for HER2-low and 32.2% for HER2-negative (P< 0.05) and among hormone receptor-positive patients, the corresponding rates were 60.9% and 55.6% for HER2-low and HER2-negative cases, respectively ( P< 0.05). HER2-low cases demonstrated improved survival in multivariable regression analysis (HR = 0.95, 95% CI 0.91-0.99) and propensity-matching (HR = 0.92, 95% CI 0.89-0.96).
In a subset analysis focusing on hormone receptor-positive cases, HER2-low status remained associated with better survival (HR = 0.93, 95% CI 0.89-0.98) in propensity-matched multivariable regression analysis. Correlates of worse survival included older age as a continuous variable (HR = 1.02, 95% CI 1.02-1.02) and Black race (HR = 1.26, 95% CI 1.20-1.32) [all P< 0.01].
This study, the largest analysis conducted to date, revealed a statistically significant association of HER2-low tumors that exhibited improved survival compared to HER2-negative tumors in MBC. No funding was provided for the study.
Source: https://pubmed.ncbi.nlm.nih.gov/38379326/
Neubauer Z, Hasan S, Press RH, et al. (2024) ‘’Prognostic implications of HER2NEU-low in metastatic breast cancer.’’ Cancer Med. 2024 Jan;13(2):e6979. doi: 10.1002/cam4.6979.
