Background: When a breast lesion is suspected based on a physical exam, mammography, or ultrasound, a stereotactic core needle biopsy (CNB) is usually performed to help establish a definitive diagnosis. CNBs are far less invasive than excisional biopsies, with no need for general anesthetics or hospitalization, and no recovery period. However, since only samples of the mass are removed in a CNB and not the whole mass, sampling errors can occur.
Objectives: To compare the degree of agreement between the pathological data from CNBs and excisional biopsies from a single tertiary referral hospital.
Methods: The concordance of pathological data was compared in patients who underwent CNBs and had their surgical procedures at the same medical center.
Results: From the 894 patients who underwent CNBs, 254 (28.4%) underwent subsequent excisional biopsies at our medical center. From the total of 894 patients, 227 (25.3%) who underwent a CNB were diagnosed with a malignancy, with the rest of the CNBs being diagnosed as benign pathologies. The pathological findings in the CNBs and in the excisional biopsies concurred in 232/254 (91.3%) of the cases.
Conclusions: A CNB to confirm mammographic or clinical findings of breast lesions is an accurate method to establish a pathological diagnosis of breast lesions. The accuracy is higher for invasive carcinomas than for non-invasive cancers. Excisional biopsies are necessary for lesions with anticipated sampling errors or when the core needle biopsy findings are discordant with clinical or mammographic findings.