Shear-wave elastography guided core needle biopsy for the determination of breast cancer molecular subtypes

Purpose The aim of this study was to investigate the role of shear-wave elastography (SWE) guided-core needle biopsy of breast masses for the accurate determination of breast cancer immunohistochemical subtypes. Material and Method This controlled randomized prospective cohort study, which was carried out in the Dokuz Eylül University Medical Faculty Department of Radiology between May 2018 and April 2019, included adult patients who had a breast lesion larger than 1 cm and were referred for a core needle biopsy. Patients were divided into two groups by block randomization. B-Mode ultrasonography (USG)-guided biopsy was performed in thirty lesions as a control group (group 1) and SWE guided biopsy was performed in thirty lesions (group 2). The biopsy in control group was recorded as biopsy A, SWE guided biopsy from the relatively rigid area of the lesion was recorded as biopsy B and biopsy from the relatively less rigid area of the lesion was recorded as biopsy C. Diagnosis and immunohistochemical results of the lesions were recorded and compared with the surgical results. Results The mean age of the patients was 57.7 ± 18.5 in group 1 and 56 ± 13.7 in group 2; lesion sizes were 33.2 ± 22.6 mm in group 1, 27.8 ± 11.9 mm in group 2 and there was no significant difference between groups (p> 0.05). Sensitivity was 96.7% in biopsy A and 100% in biopsy B and C. Benign-malignant accuracy was 94.7%, 100% and 90% and diagnostic accuracy was 89.5%, 100% and 90% in biopsy A, B and C, respectively. When immunohistochemical markers were evaluated; in one patient (14.3%) at biopsy A, Her2 receptor status was wrong. When the 10% difference in ER, PR and Ki67 rates were considered significant, the accuracy of ER was highest in biopsy B as 77.8% (p = 0.04). Accuracy in immunohistochemical subtyping was 100% in biopsy B, 71.4% in biopsy A and C (p = 0.08). Conclusion SWE-guided core needle biopsy of breast lesions increased sensitivity, diagnostic accuracy and accuracy in immunohistochemical subtyping to 100%.