Pathological Complete Response with Platinum Containing Neoadjuvant Chemotherapy in Triple-negative Breast Cancer: An Interventional Study

Abstract

Introduction: Triple-negative Breast Cancer (TNBC) accounts for 20% of all breast cancer cases globally and responds well to cytotoxic chemotherapy. The standard Neoadjuvant Chemotherapy (NAC) regimen for TNBC includes 4+4 cycles of anthracycline, cyclophosphamide, and taxane. Integrating platinum agents into the NAC has gained attention as an effective treatment for TNBC. Aim: To estimate the proportion of pathological Complete Response (pCR) in TNBC patients receiving platinum-based NAC. Materials and Methods: This interventional study enrolled 73 non metastatic TNBC patients who attended the radiotherapy Outpatient Department (OPD) of Government Medical College Thiruvananthapuram Kerala, India from April 2022 to April 2023. All patients underwent a complete history, physical examination, and tumour histopathology with Oestrogen Receptor (ER), Progesterone Receptor (PR) and Human Epidermal Growth Factor Receptor 2 (HER2) receptor status assessment. Patients were treated with the NAC regimen: Epirubicin 90 mg/m2 , Cyclophosphamide 600 mg/m2 intravenously every three weeks for four cycles followed by Paclitaxel 175 mg/ m2 , Carboplatin according to Area Under Curve (AUC)-5 by intravenous administration every three weeks for four cycles. Clinical response was evaluated after the completion of NAC using Response Evaluation Criteria in Solid Tumours (RECIST) criteria. pCR assessment was conducted postsurgery. Study variables were entered into Microsoft Excel, and the analysis was performed using Statistical Packages for Social Sciences (SPSS) version 24.0. Results: Out of 73 patients with a mean age of 54.4 years, 33 (45.2%) patients showed complete response on clinical examination after eight cycles of Carboplatin-containing NAC, and 23 (31.5%) patients achieved pCR. Total 30 (41.1%) patients experienced complications during chemotherapy, with neutropenia and peripheral neuropathy being the most common, each occurring in 22 (30.1%) patients. Conclusion: In present study, one-third of the patients achieved pCR with platinum-based NAC with an acceptable side-effect profile. It represents a beneficial treatment option for TNBC patients; however, the impact of pCR on survival requires further validation through long-term studies. Given the poor prognosis and limited treatment options for TNBC, the addition of affordable and available agents to the existing chemotherapy regimen could potentially revolutionize the treatment of these patients.