Audit of nottingham system grades assigned to breast cancer cases in a Teaching Hospital

Background: Histologic grade of breast cancer is a Category I prognostic factor. Thus, accurate and reproducible grading must be ensured by periodic auditing and training. Objective: The objective of this study is to audit interobserver agreement in grading and evaluate agreement of grading on core needle biopsies with surgical pathology. Materials and Methods: Slides of 73 cases of invasive carcinomas of the breast were retrieved from archives. These were grouped into 43 cases on which consensus grades assigned by 3 pathologists were compared with initial grades assigned to the cases. The next 24 cases were graded independently by 4 pathologists and compared. In the last 6 cases, consensus grades were assigned to both the initial core needle biopsy (CNB) and the excisional biopsy. Kappa values were then calculated. Results: Kappa value (κ) for the first 43 cases was 0.50 (moderate agreement; P P P Conclusion: To ensure reproducibility, greater attention should be paid to accurately assessing nuclear pleomorphism and mitotic activity in particular. Re-grading of excisional breast biopsies after initial CNB is also essential to prevent undergrading.