The Accuracy of Core Needle Biopsy in Determining Histological Type and Scarf-Bloom-Richardson Grade in Invasive Breast Cancer

Background: Core needle biopsy (CNB) is a widely used, minimally invasive diagnostic tool in breast cancer. This study aimed to evaluate the accuracy of CNB in determining the histological type and Scarff-Bloom-Richardson (SBR) grade in invasive breast cancer compared to surgical pathology. Methods: This prospective study was conducted over two years at a tertiary care center in Eastern Uttar Pradesh, involving 72 patients with suspected invasive breast cancer. All patients underwent CNB followed by a definitive surgical excision. Histological type and SBR grade were determined for both CNB and surgical specimens, and concordance rates were calculated. Results: The concordance rate for histological type between CNB and surgical specimens was 95.8%, with the highest agreement observed for invasive ductal carcinoma. For SBR grading, the overall concordance was 88.9%, with Grade II tumors showing the highest agreement (94.7%). Discrepancies were primarily due to sampling errors and tumor heterogeneity. Statistical analysis showed substantial to almost perfect agreement (kappa coefficients: 0.72 for grade, 0.85 for type). Conclusion: CNB demonstrated high accuracy in diagnosing the histological type and SBR grade in invasive breast cancer, reinforcing its role as a critical preoperative diagnostic tool. Enhancements in sampling techniques and grading criteria could further improve its precision.