1. HER-2 low status in early-stage invasive lobular carcinoma of the breast: associated factors and outcomes in an institutional series
- Author
-
Rothschild, Harriet T, Clelland, Elle, Patterson, Anne, Molina-Vega, Julissa, Kaur, Mandeep, Symmans, W Fraser, Schwartz, Christopher J, Chien, A Jo, and Mukhtar, Rita A
- Subjects
Biomedical and Clinical Sciences ,Oncology and Carcinogenesis ,Cancer ,Breast Cancer ,Humans ,Female ,Breast Neoplasms ,Carcinoma ,Lobular ,Carcinoma ,Ductal ,Breast ,Prognosis ,Receptor ,ErbB-2 ,Disease-Free Survival ,Invasive lobular carcinoma ,HER2-low ,Early-stage ,Receptor ,erbB-2 ,Clinical Sciences ,Oncology & Carcinogenesis ,Clinical sciences ,Oncology and carcinogenesis - Abstract
PurposeHER2 overexpression has a central role in breast cancer carcinogenesis and is associated with poor prognosis if untreated. Lately, identification of HER2-low breast cancer has been proposed to select patients for novel HER2-directed chemotherapy and includes cancers with immunohistochemistry 1 + or 2 + with negative FISH, encompassing approximately 55-60% of all breast carcinomas. In early-stage breast cancer, the prognostic significance of HER2 low-disease is less well understood, with a particular paucity of data evaluating the prevalence and implications of HER2-low status in invasive lobular carcinoma (ILC).MethodsWe evaluated 666 stage I-III ILC tumors from a prospectively maintained institutional database, comparing clinicopathologic features and disease-free survival (DFS) using a multivariable Cox proportional hazards model.ResultsHER2-low status was common in this cohort of patients with ILC, but most clinicopathologic features did not differ between HER2-low and HER2-negative cases. However, when adjusting for tumor size, number of positive nodes, ER/PR status, and local therapy received, patients with HER2-low status had worse disease-free survival (DFS) than those with HER2-negative tumors (hazard ratio 2.0, 95% confidence interval 1.0-4.1, p = 0.05).ConclusionThis difference in DFS supports the notion that HER2-low and HER2-negative early stage ILC may differ clinically, despite similar clinicopathologic features. Further investigation into the potential benefit of HER2 targeted therapy in HER2-low early-stage breast cancer, and specifically lobular cancer, is warranted to ensure optimal outcomes in this distinct tumor subtype.
- Published
- 2023