Neoadjuvant Chemotherapy Plus Panitumumab in Inflammatory Breast Cancer
Posted: Monday, September 17, 2018
Possibly the highest pathologic complete response rate ever reported in triple-negative inflammatory breast cancer was achieved with a combination of panitumumab and neoadjuvant chemotherapy, according to study results reported in JAMA Oncology. Although treatment-related hematologic and dermatologic side effects were “substantial,” they were “transient,” noted Naoko Matsuda, MD, of The University of Texas MD Anderson Cancer Center, Houston, and colleagues.
Enrolled between 2010 and 2015, 40 women with HER2-negative inflammatory breast cancer (19 with triple-negative disease; 21 with hormone receptor–positive disease) were treated in a single-arm, open-label trial. The primary endpoint, pathologic complete response rate, was 42% in patients with triple-negative disease and 14% in patients with HER2-negative, hormone receptor–positive disease. The median follow-up was 19.3 months; the median patient age was 57.
EGFR expression is an independent predictor of low overall survival in patients with inflammatory breast cancer. The hope was that the anti-EGFR antibody panitumumab, given with neoadjuvant chemotherapies including nab-paclitaxel, carboplatin, fluorouracil, epirubicin, and cyclophosphamide, would improve the pathologic complete response rate.
Safety was the study’s secondary endpoint. Rash was the most frequent nonhematologic side effect reported with this therapy. Of the 10 patients treated with panitumumab, nab-paclitaxel, and carboplatin who were hospitalized for treatment-related events, 5 had neutropenia-related events. Although treatment-related hematologic and dermatologic toxic effects were considered to be substantial, they were transient, and no treatment-related deaths occurred.
“A randomized phase II study is ongoing to determine the role of panitumumab in patients with triple-negative inflammatory breast cancer and to further validate predictive biomarkers,” Dr. Matsuda and colleagues added.