Retrospective study of efficacy and safety of neoadjuvant docetaxel, carboplatin, and trastuzumab in HER2-positive locally advanced and oligometastatic breast cancer: An Indian experience

BACKGROUND: The neoadjuvant chemotherapy in HER2-positive breast cancer consists of a chemotherapy backbone and HER2-directed therapy. The increase in cardiotoxicity by the use of trastuzumab with an anthracycline-based regimen has led to the use of nonanthracycline-based alternative regimens. The docetaxel, carboplatin, and trastuzumab (TCH) are one such regimen. The efficacy and toxicity of this regimen have not been widely studied in Indian patients. AIMS: This retrospective study aims to evaluate the efficacy and toxicity of neoadjuvant TCH regimen in locally advanced and oligometastatic HER2-positive breast cancer in Indian patients. METHODOLOGY: The hospital records between January 2014 and December 2016 were reviewed to identify patients with locally advanced and oligometastatic HER2-positive breast cancer treated with uniform 3-weekly neoadjuvant chemotherapy protocol-containing docetaxel (75 mg/m(2)), carboplatin (AUC = 6), and trastuzumab (8 mg/kg loading followed by 6 mg/kg) (TCH). The primary outcome was the pathologic complete response (pCR), which was defined as an absence of invasive and noninvasive cancer in breast or lymphnode. RESULTS: Thirty-two patients with mean age 46 years met our inclusion criteria, of these 24 patients had locally advanced breast cancer, and eight patients had oligometastatic breast cancer. 13 (40.6%) patients had hormone-positive breast cancer. The objective response rate as assessed clinically was 100%, and pCR rate was 36.3%. The patients with oligometastatic breast cancer also showed a good response to chemotherapy with three patients showing pCR and four patients showing resolution disease at metastatic sites. The patients experienced very few Grade III/IV toxicities, and no patient had clinical congestive heart failure. CONCLUSION: The TCH protocol is an efficacious neoadjuvant chemotherapy regimen for locally advanced and oligometastatic breast cancer and is safe and well tolerated in this population.