Expert Discusses Breast Conservation Therapy’s Impact on Recurrence for Multiple Ipsilateral Breast Cancer

Breast surgeons and multidisciplinary teams should discuss the risks and benefits of both breast conservation therapy and mastectomy with their patients as treatment options for multiple ipsilateral breast cancer, according to Judy C. Boughey, MD, a surgical oncologist of the Division of Breast and Melanoma Surgical Oncology and the Department of Surgery at Mayo Clinic in Rochester, Minnesota.

During the 2022 San Antonio Breast Cancer Symposium (SABCS), CancerNetwork^® spoke with Boughey about her research on the impact of breast conservation therapy on local recurrence rates among patients with multiple ipsilateral breast cancer in the phase 2 ACOSOG Z11102 (Alliance) trial (NCT01556243).

Boughey described a few key takeaways from her research, including how receiving preoperative MRIs or prior adjuvant endocrine therapy to detect and minimize the risk of local recurrence among patients. She also went into detail as to which patients may be most suitable to benefit from breast conservation therapy based on factors such as age and number of sites of disease.

Transcript:

The takeaway points from this research are that if surgeons and multidisciplinary teams are seeing a patient that has 2 or 3 foci of breast cancer within 1 breast, they [should] evaluate that patient with their standard workup and then discuss with the patient not only the option of mastectomy, but also potentially the option of breast conserving therapy. And if the patient is interested in preserving that breast, one of the interesting findings in this study—which was an unplanned analysis—was that the local recurrence rate was higher in those patients who didn't have a preoperative MRI. For patients who are planning to proceed with breast conserving therapy for multiple ipsilateral breast cancer, it would be a reasonable consideration to get a preoperative MRI to assess for the extent of disease and then offer them the option of proceeding with breast conserving therapy.

One of the other findings of the trial was that for those patients with endocrine therapy–sensitive tumors, the adjuvant endocrine therapy was important in terms of minimizing risk of local recurrence, as it is in patients with unifocal breast cancer. That would also be an important part of the conversation to ensure that patients are interested in taking endocrine therapy in the adjuvant setting and adhering to it.

When you look at the patient population who was enrolled in this study, it was limited to women over the age of 40. We didn't have any patients treated with any neoadjuvant therapy and the vast majority of the patients on this trial had just 2 foci of disease; very few patients had a third foci of the disease. The group of patients [best suited for treatment when] incorporating this into clinical practice is going to be women over 40 [years old] with 2 sites of disease treated with breast conservation and then whole breast radiation with booster [to] each lumpectomy side.

Reference

Boughey JC, Rosenkranz KM, Ballman KV, et al. Impact of breast conservation therapy on local recurrence in patients with multiple ipsilateral breast cancer – results from ACOSOG Z11102 (Alliance). Presented at the 2022 San Antonio Breast Cancer Symposium; December 6-10, 2022; San Antonio, TX; abstract GS4-01.