Diagnostic concordance between core needle biopsy and excision in breast lesions: An audit of the National Health Service Breast Screening Programme histopathological classification in a tertiary care center
Sunila Jain, Md Ali Osama, Aditi Aggarwal, Rakesh Koul, Madhavi Chandra
A
BSTRACT
Objectives:
Core needle biopsy (CNB) is central to the preoperative evaluation of breast lesions. The UK National Health Service Breast Screening Programme (NHSBSP) classification (B1–B5) standardizes histopathological reporting, but its real-world application in Indian practice remains under-evaluated.
Materials and Methods:
This retrospective observational study analyzed 139 breast CNBs reported using the NHSBSP classification between December 2020 and January 2024. Fifty-five cases had corresponding surgical excision specimens available for correlation. Concordance between CNB and excision was assessed for diagnostic category, tumor subtype, and grade. Diagnostic performance metrics were calculated using excision histology as the reference standard.
Results:
Among 139 CNBs, 81 (58.3%) were malignant (B5), 28 (20.1%) borderline (B3), and 30 (21.6%) benign (B1/B2). Overall complete concordance between CNB and excision was 61.1%. This relatively modest concordance reflects the stringent definition adopted in the present study, requiring agreement not only in benign versus malignant categorization but also in tumor subtype and histological grade, and should therefore not be equated with the diagnostic accuracy of CNB for distinguishing benign from malignant disease. Benign lesions showed 100% concordance. Borderline (B3) lesions demonstrated a malignancy upgrade rate of 15.4%. Invasive malignancies (B5b) showed 90.6% concordance, with subtype discrepancies in 9.4%. Tumor grade concordance among invasive carcinomas was 78.8%. Within the excision-correlated cohort, CNB demonstrated 100% sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy for definitive benign (B1/B2) and malignant (B5) lesions.
Conclusion:
When interpreted using the NHSBSP framework, CNB reliably distinguishes benign from malignant breast lesions in routine Indian practice. However, limitations persist in borderline lesions, tumor grading, and precise subtyping, underscoring the continued need for surgical excision in indeterminate cases.