Pathological predictive factors for tumor response in locally advanced breast carcinomas treated with anthracyclin-based neoadjuvant chemotherapy

Aim: Neoadjuvant chemotherapy (NACT) is used as a primary treatment for locally advanced breast carcinoma (LABC) and also extended to operable breast cancer. The aim of this study was to evaluate the predictive value of different histological parameters in core biopsy of LABC patients treated with anthracycline-based chemotherapy regimen. Pathological assessment of the excised tumor bed is the gold standard and is essential for identifying the group of patients with pathologic complete response (pCR) or pathologic noncomplete response (pNR). Materials and Methods: A total of 50 patients with stage II and III breast carcinoma were included in the study. Pretreatment core biopsy histological features include tumor type, histological grade, presence of tumor necrosis, lymphovascular emboli (LVE) and immunohistochemical stains for estrogen receptor (ER) and progesterone receptor (PR) were obtained. Patients were given 3-6 cycles of NACT. Pathological response was assessed. Result: Seven out of 50 patients achieved pCR. A total of 71.4% patients who achieved pCR had tumor necrosis on initial core biopsy while only 30% pNR cases had this feature (P=0.035). Breast carcinoma other than ductal type was chemoresistant. Of 47 core biopsies, LVE was observed in 13 cases (28 %) of which 11 showed axillary node metastasis. None of these 13 cases had pCR, thus having poor predictive value. Conclusion: Pathological parameters like type of tumor, presence of LVE and tumor necrosis in the core biopsy can predict the response to NACT in routine stain. Tumor necrosis and type of breast carcinoma are predictive parameters for tumor responsiveness to NACT. LVE was reliable in predicting axillary lymph node metastasis.