Breast Cancer Paradigm Moves Toward Less Morbid Treatments With Improved Risk Assessment and Imaging Strategies

Improved risk assessment and imaging strategies have underscored the need for early disease detection in patients with breast cancer, said Paul Lawrence Baron, MD, who added that early identification can capitalize on less morbid therapeutic approaches, such as lumpectomies, systemic targeted therapies, and hyperfractionated radiation therapy.

“[We’ve seen] a lot of things to be optimistic about [in the management of] breast cancer. Survival seems to be [improving], and we are using less morbid treatments for these patients,” said Baron, chief of breast surgery and director of the Breast Cancer Program at Lenox Hill Hospital of Northwell Health, in an interview with OncLive^® during an Institutional Perspectives in Cancer (IPC) webinar on breast cancer.

The virtual meeting covered the identification and management of patients at high risk of developing breast cancer, strategies for treating patients with early-stage and metastatic HER2-positive breast cancer, updates in breast imaging, and controversies surrounding breast radiation therapy.

In the interview, Barron discussed best practices for determining a patient’s risk of developing breast cancer, the significance of targeting HER2 in patients with early-stage and metastatic disease, and remaining questions with radiation therapy in the field.

OncLive^®: What are the current means of determining someone’s risk of developing breast cancer?

Baron: We frequently use the Tyrer-Cuzick model, which is a calculated model that gives us an idea of what the patient’s lifetime risk is. If [the risk] is over 20%, those patients are considered high risk and require close imaging follow-up. If [the Tyrer-Cuzick score] is 15% or less, they are average-risk patients, and [those patients] don’t require [close imaging follow-up].

In the high-risk patients, in addition to doing 3D mammograms, we frequently use breast MRI as a supplement [follow-up technique].

What factors contribute to someone’s risk of developing breast cancer?

A high-risk patient is somebody who has inherited a gene that increases their risk of breast cancer. The most common [alterations] we talk about are BRCA1 and BRCA2. We also look at whether the patient has a previous history of radiation to their chest because those patients have an increased risk for developing breast cancer. [Other] patients with a high risk of developing breast cancer [include those with] a very strong family history but [without] a known genetic mutation, those who have had a previous biopsy that showed atypical hyperplasia or lobular carcinoma in situ, or those with dense breast tissue. Those are some of the high-risk features that we identify in patients and [in whom] require very close follow-up.

During the IPC meeting, Lisa Baron, MD, of Northwell Health discussed updates with breast imaging. What are some best practices for screening patients who are at risk of developing breast cancer and how could improving imaging techniques benefit patients?

The most common recommendation is to do 3D mammography on patients. That is the best way of screening patients. We recommend getting a baseline mammogram on somebody 40 years of age and then once a year going forward. If the patient is high risk, we frequently supplement [3D mammography] with a breast MRI, which is done about 6 months later. We try to alternate one test with the other every 6 months. Those are the common [tests], but we frequently also use breast ultrasound, which helps with mammogram as a screening tool.

Those are the 3 main modalities commonly used and strongly advocated for in screening patients for breast cancer. However, some new techniques are coming down the pike that we learned about [during the IPC meeting] from the imaging portion. [Some of these techniques] include contrast-enhanced mammography, which is for patients who, for various, reasons don’t want to or can’t have an MRI. [In these cases], patients get a small amount of contrast with the mammogram. It’s a very sensitive way for finding additional lesions that are not well seen on the mammogram.

Francisco Esteva, MD, PhD, of Northwell Health, spoke to management strategies in HER2-positive breast cancer. How has the integration of trastuzumab (Herceptin) and pertuzumab (Perjeta) transformed clinical practice in the neoadjuvant and adjuvant settings?

Clearly, it was a huge success story in identifying that patients who have HER2-positive cancer benefit from trastuzumab and pertuzumab, which lowers their risk of the cancer coming back. In patients who require neoadjuvant therapy, we see their tumors disappear. Patients who get [trastuzumab and pertuzumab] as adjuvant therapy have a very low risk of the cancer coming back. It was a huge success in breast cancer treatment in the past 20 years.

Next, Anna Komorowski, MD, of Northwell Health, discussed treatment approaches in HER2-positive metastatic breast cancer. What does it mean for the field to have HER2 as a target in the metastatic setting?

Although we are never happy to see someone with metastatic disease, we were very happy to have a target with HER2 [emerge] because at least then we had something to target. We have a lot of answers and new drugs coming down the pike targeting patients with metastatic HER2-positive breast cancer to improve long-term outcomes.

Finally, Seth R. Blacksburg, MD, of Northwell Health, commented on controversies surrounding breast radiation therapy. How do you view the role of axillary lymph node radiation in breast cancer?

In the past, the standard treatment was that if somebody had a positive lymph node, we would do an axillary lymph node dissection. However, the data have shown that if patients have a positive node, they do just as well from a survival standpoint with axillary radiation therapy vs axillary dissection. [Patients who undergo] axillary radiation therapy seemed to have less morbidity vs those who have axillary [dissection]. There is a lot of promise for using axillary radiation for those patients.

What key points from the IPC meeting should be underscored for the breast cancer community?

The take-home message is for those dealing with breast cancer, we have made huge strides in identifying patients at a high risk of developing disease. Certainly, if we identify those patients with cancer early, they get a better chance at survival and a lower likelihood of needing a mastectomy. When we find [the disease] early, it is small and treatable.

We have a lot of advances in imaging, so we are helping to find these cancers early. Most of my practice is outpatient surgery because most patients can have a lumpectomy and do not require mastectomies these days. We still do mastectomies on a selective basis, but that is in a minority of cases.

We have made huge advances in systemic therapy, especially with targeted therapy against the HER2 protein. [This has led to] major changes in outcomes for patients.

Finally, people use to believe that radiation therapy was a high-morbidity treatment. However, in many ways, [radiation therapy] has become less morbid than some of the other surgical modalities we are doing. In many cases, patients don’t need radiation, or if they do, it is a shorter course of hyperfractionated radiation.