Insights on ER+ Breast Tumors and Immune Characteristics

Core Concepts

Breast tumors with low ER expression may benefit from immune checkpoint inhibitor therapy.

Abstract

The research suggests that breast tumors with low and intermediate estrogen receptor (ER) expression exhibit immune characteristics similar to triple-negative breast cancer (TNBC). The study found comparable levels of immune factors and gene signatures in tumors with ER expression between 1%-50% and those with no ER expression. This challenges the current treatment guidelines and opens up the possibility of immune checkpoint inhibitor therapy for ER+ breast tumors.

Stats

"Currently immune checkpoint inhibitor (ICB) therapy is only approved for TNBC."
"The team found similar expression of immune-related gene signatures between breast tumors with varying levels of ER expression."
"The study focused on primary tumors from 173 patients with HER2-negative breast cancer."

Quotes

"Please stop treating ER low disease like it is standard HR+ breast cancer. It's not." - Rebecca Shatsky, MD
"Increasing evidence on similarity between ER low and TNBC. Time to redefine what's [an] ER negative BC." - William Mantilla, MD

Key Insights Distilled From

Practice-Changing Data on Low ER+ Breast Tumors?

by Megan Brooks at www.medscape.com 06-01-2023

https://www.medscape.com/viewarticle/992641

Deeper Inquiries

How can the findings of this study impact the current treatment guidelines for ER+ breast tumors?

The findings of this study suggest that breast tumors with low and intermediate estrogen receptor (ER) expression exhibit immune characteristics similar to triple-negative breast cancer (TNBC). This implies that patients with low and intermediate ER-positive breast cancer might benefit from immune checkpoint inhibitor (ICB) therapy, challenging the current selection criteria based on ER negativity. As a result, these findings could potentially lead to a reevaluation of the treatment guidelines for ER+ breast tumors. Oncologists may need to consider incorporating ICB therapy for patients with low and intermediate ER-positive tumors, expanding the treatment options beyond traditional endocrine therapies.

What are the implications of redefining ER-negative breast cancer based on immune characteristics?

Redefining ER-negative breast cancer based on immune characteristics could have significant implications for patient management and treatment strategies. By recognizing the similarities between ER low-positive tumors and TNBC in terms of immune features, clinicians may need to reconsider how they classify and approach ER-negative disease. This redefinition could lead to a more personalized and targeted treatment approach, where patients with ER low-positive tumors are considered for therapies traditionally reserved for TNBC, such as immune checkpoint inhibitors. Understanding the immune characteristics of ER-negative breast cancer could pave the way for more tailored and effective treatment options for this subset of patients.

How can the similarities between ER low-positive tumors and TNBC influence future research in breast cancer treatment?

The similarities between ER low-positive tumors and TNBC uncovered in this study could significantly influence future research in breast cancer treatment. By recognizing the immune characteristics shared by these two subtypes, researchers may explore new treatment avenues that target the immune microenvironment in ER low-positive tumors. This could lead to the development of novel therapies, such as immune checkpoint inhibitors, specifically tailored for patients with low ER expression. Additionally, these findings may prompt further investigations into the underlying mechanisms driving the immune response in ER low-positive tumors and how they differ from traditional ER-positive breast cancer. Overall, understanding the similarities between ER low-positive tumors and TNBC could open up new research opportunities aimed at improving outcomes for patients with these subtypes of breast cancer.