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

Abstract

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. 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. 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/m2), 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. 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. 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.