A Trial of Neoadjuvant, Hypofractionated Radiation, With Intratumoural Pembrolizumab Followed by Neoadjuvant Chemotherapy, in Stage 3 or High-risk Stage 2 Breast Cancer
This study will evaluate the immune-priming effects of stereotactic body radiation therapy (SBRT) regimen coupled with two injections of pembrolizumab in high-risk primary breast carcinoma prior to neoadjuvant chemotherapy. Preliminary results from the investigators' local TRIO Trial suggest that SBRT prior to neoadjuvant chemotherapy (NAC) may result in improved response rates due to the combined effect of radiation therapy (RT) and chemotherapy. The investigators aim to augment this effect with the addition of pembrolizumab, a monoclonal antibody that binds to and blocks programmed cell death protein 1 (PD-1).
• Invasive ductal carcinoma of any subtype (including invasive mammary carcinoma with lobular features), excluding sarcomatous, signet or metaplastic subtypes.
• Invasive mammary carcinoma of stages IIB - III (excluding inflammatory breast cancer). Stage IIA is eligible for triple negative and HER2+ breast cancers.
• a. Clinical staging based on AJCC 8th edition.
• Lesion palpable by treating physician.
• Plan to be treated with neoadjuvant chemotherapy.
• Able to tolerate core needle biopsies and pembrolizumab injection.
• 18 years of age or older.
• Able to provide informed consent.