ABSTRACT: This phase I/II neoadjuvant trial determined maximally-tolerated doses (MTD), dose-limiting toxicities (DLT), response-to-therapy, and explored the role of new response biomarkers. The combination regimens were delivered with acceptable toxicity, good clinical response, inducing changes in tumor RNA content and integrity. Pre-treatment gene expressions impacted clinical response, including several near 17q12, which with ERBB2, may better identify chemoresponsiveness. The NCIC Clinical Trials Group MA.22 phase I/II clinical trial (ClinicalTrials.gov identifier NCT00066443) sought to determine the optimal dosing regimens for docetaxel/epirubicin combination chemotherapy in women with locally advanced (over 95% of patients) or inflammatory breast cancer. The protocol was approved by Health Canada and local Ethics Review Boards, and patients provided written, informed consent. Various doses of epirubicin and docetaxel were administered to patients in either a standard q3 weekly (Schedule A) or dose dense q2 weekly (Schedule B) regimen. Doses for Schedule A were 75 mg/m2 IV of docetaxel and 75, 90, 105, or 120 mg/m2 IV of epirubicin (with 6 mg of pegfilgrastim per cycle on day 2 to prevent neutropenia). Doses for both docetaxel and epirubicin in Schedule B were 50, 60, and 70 mg/m2 IV (with identical pegfilgrastim support). For each schedule, phase I was dose finding for phase II. Patients were allocated to the various phases and dosing regimens of the trial without randomization. None of the patients received trastuzumab in the initial years of the study and HER2+ patients were not enrolled on study, once trastuzumab funding became available. Six tumor biopsy cores were obtained pre-, mid-, and post-treatment: 3 cores for pathologic assessment; 3 cores for microarray studies. Total RNA was isolated from these cores and RNA integrity was assessed using Agilent Bioanalyzer. One of the RNA samples with the best quality was used for microarray study. One colour microarray of Agilent whole human genome nucleotide arrays was conducted with one array per patient. The current data set represents pre-treatment set. MA.22 clinical trial accrued T3N0, any N2 or N3, and T4 breast cancer patients (according to the classification described at; http://emedicine.medscape.com/article/2007112-overview). However, since the current study does not focus on the tumor grade/stage, the information was not provided in the current records.
