Dr. Peter Beitsch on Pertuzumab in Luminal Subtype Breast Cancer

Peter Beitsch, MD, president of The American Society of Breast Surgeons, Dallas Surgical Group, discusses the impact of pertuzumab on patients with luminal subtype breast cancer.

Triple-positive patients, who are ER-positive, PR-positive, and HER2-neu positive, respond less to chemotherapy plus trastuzumab than those who are ER-negative. The reason for this has never been well understood, says Beitsch.

Based on the Neoadjuvant Breast Registry - Symphony Trial (NBRST), triple-positive patients were broken into two groups—HER2-neu driven and luminal subtype. It was determined that there was almost a pathological complete response (pCR) with chemotherapy plus trastuzumab in the luminal subtype, while those who were HER2-neu driven saw a response, says Beitsch.

Over the course of the study, pertuzumab was added as part of the standard of care to chemotherapy plus trastuzumab. This increased pCR rates in the luminal subtype group.