Visual assessment of the Ki67 index in breast cancer using the global scoring

Introduction. Neoadjuvant therapy (NAT) provides an in vivo assessment of primary tumor sensitivity to systemic therapy. However, the data on Ki67 clinical significance as a prognostic factor for effectiveness chemotherapy breast cancer (BC) cause controversy. The International Interpretation Workgroup Breast Cancer (IKWG) meeting held October 2019, recommended developing standardized methodology visual global scoring, which is proposed be used practice. aim study was assess using scoring BC. Materials and methods. included 32 patients with proven BC that received preoperative neoadjuvant We studied paraffin histological blocks, analyzed expression over time residual tumors, assessed correlations morphological signs before treatment. determined overall average scoring. app smartphones auxiliary tool increase accuracy. Results. median value index NAT 75.0% (34.8–85.0) after it 1.0% (0.0–6.2) [p<0.0001]. significantly lower (p=0.0077) [36% (30–75)] presence compared without [85% (78.8–90)]. Conclusion. strongly its effectiveness. research marker concomitant diagnosis, showed role, can considered correct diagnostic vector, only if strict analytical validity observed. Keywords: Ki67, cancer, therapy, IKWG,