Concurrent Neoadjuvant Chemotherapy and Radiation Therapy in Locally Advanced Breast Cancer

Purpose: To evaluate whether concurrent neoadjuvant radiation added to standard chemotherapy could increase the pathologic complete response (pCR) to treatment for locally advanced breast cancer (LABC). Methods and Materials: This prospective phase 2 trial recruited 32 LABC patients from 2009 to 2011. Patients received neoadjuvant every-3-weekly 5-fluorouracil (500 mg/m(2)), epirubicin (100 mg/m(2)), and cyclophosphamide (500 mg/m(2)) for 3 cycles, followed by weekly docetaxel (35 mg/m(2)) for 9 cycles. Regional radiation (45 Gy/25 plus 5.4 Gy/5) was delivered concurrently with docetaxel, then modified radical mastectomy. Patients were matched post hoc by a blinded statistician to a concurrent cohort treated with neoadjuvant chemotherapy, modified radical mastectomy, and adjuvant regional radiation. Results: Thirty of 32 patients completed treatment. Twenty-seven were successfully matched by propensity score to 81 control patients by age, stage, and molecular subtype. The concurrent chemoradiation produced a significant increase in pCR (14% vs 22%, P<. 001) but no statistically significant difference in disease-free and overall survival at 3 years (respectively, 69% vs 81%, PZ. 186, hazard ratio 0.51; and 74% vs 89%, PZ. 162, hazard ratio 0.46). Toxicity included 25% of patients with grade 3 pneumonitis and 25% of patients with dermatitis, and 1 death. Conclusions: Concurrent neoadjuvant radiation added to radiosensitizing chemotherapy significantly improved pCR. A prospective randomized clinical trial is warranted to exploit the improved response seen with concurrent therapy but using another radio-sensitizing taxane, to better minimize treatment-related toxicity and determine its impact on overall survival. (C) 2017 Elsevier Inc. All rights reserved.