The accuracy of core needle biopsy in determining histological type and Scarf-Bloom-Richardson grade in invasive breast cancer

Abstract

Core needle biopsy provides information not only on the histological diagnosis but also about tumor grade and different prognosis factors for breast cancer. This study was designed to determine the accuracy of percutaneous core needle biopsy (CNB) through comparative analysis of histological diagnosis and SBR tumor grade of invasive breast cancer between CNB and surgical excision specimen (SES). This was a retrospective cross-sectional study from January 2023 to July 2023. All patients with invasive breast cancer diagnosed by CNB and confirmed by surgical excision specimen (SES) examination were included in the study. Patients who received neoadjuvant chemotherapy were excluded. One twenty-three patients were assessed. All patients were female. The median age was 45 years (37 – 54). Invasive ductal carcinoma (IDC) was the major histological type of breast cancer (95.1%) followed by invasive lobular carcinoma (ILC) (4.9%). SBR grade 2 tumors accounted for 78.1% of cases. The majority of patients presented with locally advanced stage breast cancer (65.9%) or a metastatic disease (31.7%). Concordance for histological type was substantial (k= 0.79; p<0,001) whereas it was moderate (k= 0.45; p<0,001) for Scarf-Bloom-Richardson grade. Histological type on CNB correlates almost perfectly with that of the surgical excisional specimen in case of breast cancer. Nevertheless, the agreement of tumor grade between CNB and SES remains moderate, with a significant underestimation and overestimation rates.