Pathological Complete Response after Neoadjuvant Chemotherapy and Its Influence on Surgical Decision-Making in Breast Cancer

Abstract

Background: Neoadjuvant chemotherapy (NACT) is widely used in the management of breast cancer to reduce tumour size, improve operability, and increase the rate of breast-conserving surgery. Pathological complete response (pCR) following NACT is considered an important prognostic indicator and may influence surgical decision-making.

Objectives: To evaluate the rate of pathological complete response after neoadjuvant chemotherapy and to assess its influence on surgical decision-making in breast cancer patients.

Methods: This retrospective observational study was conducted at Integral Institute of Medical Sciences and Research, Lucknow, from September 2023 to December 2025. A total of 408 patients with histologically confirmed breast carcinoma who received neoadjuvant chemotherapy followed by surgery were included. Clinical data, tumour characteristics, receptor status, and surgical procedures were collected from hospital records. Pathological complete response was defined as the absence of residual invasive carcinoma in the breast and axillary lymph nodes on final histopathology. Data were analysed using descriptive statistics, and the association between pCR and the type of surgery was evaluated.

Results: Among 408 patients, the majority were in the 41–50 years age group and most presented with stage III disease. Pathological complete response was achieved in 102 patients (25%), while 306 patients (75%) had residual disease. Breast-conserving surgery was performed in 148 patients (36.3%), whereas 260 patients (63.7%) underwent modified radical mastectomy. Patients who achieved pathological complete response were more likely to undergo breast-conserving surgery compared with those with residual disease.

Conclusion: Neoadjuvant chemotherapy plays a significant role in tumor downstaging and surgical planning in breast cancer. Achievement of pathological complete response is associated with a higher likelihood of breast-conserving surgery and reflects better treatment response.