Invasive lobular cancer represents 5-15 percent of all breast cancers (depending on the study). Although it is distinctly different and responds differently to therapy, it has been treated exactly like ductal cancer for decades.
A British research study followed more than 2,000 women for five years has found that targeting the tumor site, rather than the entire breast, was just as effective for women with early stage ductal breast cancer.
The results (open data) were published in The Lancet.
The research goal was to compare of the metastatic pattern of invasive lobular carcinoma (ILC) and invasive ductal carcinoma (IDC) at both first distant recurrence (FDR) as well as over the entire course of metastatic disease.
Invasive lobular carcinoma (ILC) is the second most common subtype of breast cancer; ILC differs from invasive ductal carcinoma (IDC) both in clinicopathological characteristics and responsiveness to systemic therapy.
Researchers from the University of North Carolina and other academic centers (more than 200 authors collaborated on this study) have identified three new subtypes of invasive lobular carcinoma. These subgroups are reactive-like, immune-related, and proliferative (n = 106).