Overexpression of human epidermal growth factor receptor 2 (HER2) protein is well known to be more frequent in ductal carcinoma in situ (DCIS) than in invasive ductal carcinoma (IDC).
This pooled retrospective analysis of three clinical studies demonstrates that the magnitude of benefit of eribulin in the metastatic setting did not differ between patients with ILC versus invasive ductal carcinoma (IDC), even when restricting for patients with estrogen receptor-positive/HER2-negative IDC.
Tumor size >2 cm (<i>P</i> = 0.023), vascular invasion (<i>P</i> = 0.011), lymphatic vessel invasion (<i>P</i> < 0.001) and HER-2+ (<i>P</i> = 0.032) were positively correlated with the degree of fibrosis in FF in breast IDC.
The main pathological parameters such as estrogen receptor (ER), progesterone receptor (PR), and human epithelial growth factor receptor 2 (C-erbB-2) were detected by immunohistochemistry (IHC), and the clinicopathologic and prognostic difference were compared with invasive ductal carcinoma (IDC).
Furthermore, coexistence of DCIS component in IDC significantly improved DFS in HER2 positive (94.8% vs 78.5%, P = 0.003), but had no association in luminal and triple negative subtypes.
Between March 2012 and February 2013, one hundred eighty seven women with ER-positive and HER2-negative IDC who underwent breast MRI and subsequent surgery were included.
Women with estrogen receptor (ER)-positive, human epidermal growth factor receptor 1 (HER2) -negative, stage I/II IDC and ILC who received endocrine therapy were identified from the 2000 to 2014 California Cancer Registry.
In this study, immunohistochemistry and fluorescence in situ hybridization (FISH) were used to assess HER2 status in 72 cases of pure DCIS, 73 cases of DCIS admixed with invasive ductal carcinoma (IDC), and 60 cases of pure IDC.
Further subgroup analysis of molecular subtype indicated improved survival in breast-ACC patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/Her2-) tumors compared to IDC patients with HR+/Her2- tumors.
Immunohistochemical staining of IDC exhibited higher degrees of positivity for ER, PR and Her2 (90, 60 and 30%, respectively) when compared with the SpCMC group, which showed a positive degree of 5.2, 5.2 and 10.5% for ER, PR and Her2, respectively (P < 0.001).
DCIS cases were classified as luminal A (46.6% in each group), luminal B (pure DCIS 20% and DCIS component of IDC 13.3%), HER2 overexpressing, basal and nonbasal (pure DCIS 3.3% and 26.6% and DCIS component of IDC 3.3% and 33.3%, respectively), and triple negative, nonbasal (pure DCIS and DCIS component of IDC 3.3% each).
Differences in ER and PR expression levels between IDC and ILC were analyzed according to age group, tumor size, axillary nodal status, grade, and HER2 status.
Multivariate analysis indicated HER2 positivity as an independent risk factor for OS, RFS, and DFS of ILC patients, which increased the risk in the ILC group than that in IDC group.
Between 2006-2012, we identified breast cancer patients with: 1) ER+, PR+, and HER2- invasive ductal carcinoma (IDC); 2) preoperative breast MRI; and 3) Oncotype Dx RS test results.