Study of the efficacy of multifocal breast biopsy in patients with a complete clinical response after neoadjuvant polychemotherapy in the combination treatment of breast cancer

Objective. To evaluate the reliability of histological multifocal biopsy results in patients with breast cancer (BC) after neoadjuvant polychemotherapy (NAPCT) with a complete clinical response (CCR). Subjects and methods. The study analyzed 35 patients with cT1—3 N0—3 M0 BC of different molecular biological types, who were diagnosed with CCR after NAPCT. All the patients underwent 12—14-gauge needle multifocal biopsy of the breast, followed by morphological study, thereafter surgical treatment was performed. Furthermore, the morphological findings of the multifocal biopsy and surgical material were compared. Results. Due to the fact that in 13 out of the 35 multifocal biopsy cases, insufficient material was obtained for morphological evi-dence for therapeutic pathomorphism, the overall sensitivity and specificity of the technique were 16.7% (CI: 4.3—45.9%) and 100% (CI: 0.2—20.6%), respectively; the false negative result was 23.8% (n=5) (CI: 11.3—41.9%), the false positive one was 0%. The overall diagnostic accuracy of the method was 77.2% (CI: 59.7—89.3%). Conclusion. To increase the percentage of reliable results for the degree of therapeutic pathomorphism in the morphological evi-dence provided by 12—14-gauge needle multifocal biopsy, it is necessary to take larger amounts of material. © 2022, Media Sphera Publishing Group. All rights reserved.