Categorization of the Histopathological Diagnosis of Breast Core Needle Biopsies and the Correlation of the Risk of Malignancy With Diagnostic Accuracy

Introduction: Core needle biopsy (CNB) is used to detect carcinoma of the breast, but it does not always provide a definitive diagnosis. Cases can be categorized into diagnostic categories to facilitate further management decisions. The United Kingdom’s National Health Service Breast Screening Program uses five “B categories” for reporting CNBs of the breast. These categories can help bring uniformity to the reporting of biopsies. Materials and methods: Biopsy cores were assigned to one of the five B categories (B1-B5). Biopsy diagnoses were then correlated with the diagnoses from the resection specimens. Sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy (DA) were calculated. Results: CNBs from 66 cases were collected and categorized as either B1, B2, B3, B4, or B5. Three of the cases (4%) were categorized as B1, eight cases (12%) were categorized as B2, four cases (6%) were categorized as B3, a further four cases (6%) were categorized as B4, and one case (1%) was categorized as B5 carcinoma in situ, while 46 cases (65%) were categorized as invasive. All four of the B3 lesions involved atypical intraductal epithelial proliferations. The SN, SP, PPV, NPV, and DA for the cases categorized as malignant B4 and B5 were 88.8, 90.9, 94.1, 83.3, and 89.6, respectively. Conclusion: More so than reports that are merely descriptive, reports that include B categorization help convey and bring uniformity to pathologists’ perspectives, especially in uncertain cases. Categorization thus facilitates communication between pathologists and clinicians and, therefore, the guidance of patient management.