Introduction: Neoadjuvant Chemotherapy (NAC) is commonly used to reduce tumor size prior to surgery, facilitating breast-conserving procedures. It also offers valuable prognostic insights by assessing the tumor's response to treatment.

Magnetic Resonance Imaging (MRI) is considered the gold standard for monitoring treatment response due to its superior sensitivity. However, its high cost, limited availability, potential to induce claustrophobia, and risk of false-positive findings have led many healthcare facilities to rely on alternative imaging techniques, such as ultrasound (USS) and mammography.

Aim: To assess the accuracy of USS and mammogram in predicting pathological response in our cohort of patients.

Method: Retrospective study of all breast cancer patients who received neoadjuvant chemotherapy from January 2021 to June 2024 and had completed their surgical treatment.

The radiological response was assessed two weeks after completion of NAC using USS and Mammogram. These results were thereafter compared with the final postoperative histology.

Results: 145 patients constitute our cohort. The mean age is 45.07+/- 9.81 years. In TNBC;14patient achieved pCR, breast USS and mammogram was accurate in all cases. (p- 1.0) Pathologic complete response was observed in 8 patients with HR +ve/ HER 2 -ve subtype, breast USS and mammogram was accurate in all of them. (p 0.47) In HR +ve /HER 2+ve tumours, 14 patients achieved pCR and 11 were accurately detected by breast ultrasound and mammogram. (p - 0.60) Conversely, in HR -ve / HER2 +ve patients, pCR was seen in 19 patients, breast USS and mammogram was accurate only in 12. (p -0.04).

Conclusion: Breast USS and MMG was accurate in predicting pCR in 96%, 94.5%,91.2% and 75.8% in TNBC, HR +ve/ Her2 -ve, HR +ve /HER 2+ve and HR -ve / HER2 +ve breast cancer respectively. Breast MRI should be recommended in both pre-NAC and post NAC for response evaluation in HR -ve / Her2 +ve breast cancer patients.