Journal of Biomedical and Clinical Research 17(1): 53-58, doi: 10.3897/jbcr.e126709

Evaluation of Ki-67 index in breast cancer cases with intratumor heterogeneity

Hristo S. Milev^‡§, Vasil Nanev^‡, Desislava Dimitrova^§, Strahil Strashilov^‡, Angel Yordanov^‡, Miroslava Mihailova-Strashilova^|, Silvia Naneva^¶, Simoneta Ivanova^#, Milena Karcheva^‡, Ivan Ivanov^‡

‡ Medical University – Pleven, Pleven, Bulgaria§ Medical University Hospital, Rouse, Bulgaria| Gastroenterology Clinic, Dr. Georgi Stranski University Hospital, Pleven, Bulgaria¶ Haematology Clinic, Dr. Georgi Stranski University Hospital, Pleven, Bulgaria# Dr. Georgi Stranski University Hospital, Pleven, Bulgaria

Corresponding author: Hristo S. Milev ( milev_hristo@abv.bg )

Academic editor: Dobromir Dimitrov

This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Citation: Milev HS, Nanev V, Dimitrova D, Strashilov S, Yordanov A, Mihailova-Strashilova M, Naneva S, Ivanova S, Karcheva M, Ivanov I (2024) Evaluation of Ki-67 index in breast cancer cases with intratumor heterogeneity. Journal of Biomedical and Clinical Research 17(1): 53-58. https://doi.org/10.3897/jbcr.e126709

Abstract

There are no specific recommendations for evaluating the Ki-67 index in heterogeneous breast carcinomas. This study aimed to evaluate the applicability of currently accepted recommendations for Ki-67 evaluation in breast cancer in the context of intratumor heterogeneity. Twelve cases of heterogeneous breast carcinomas obtained from 110 patients were retrospectively studied. Ki-67 staining was performed according to protocols provided by the reagent manufacturer. Results for Ki-67 of the separate components in each tumor were obtained, described, and analyzed statistically using a paired t-test. Values of p < 0.05 were considered as statistically significant. SPSS software was used for statistical analysis. Results from the comparison of the Ki-67 index evaluation in each heterogeneous component of the studied tumors demonstrated no statistically significant difference of mean values t = 0.4802, p = 0.6405. The anticipation of an average Ki-67 score in the evaluated cases would have changed the molecular subtype from Luminal B to Luminal A (due to the Ki-67 index below 14%) in two of the cases. Heterogeneous tumors had a different Ki-67 index in their separate components. Our observations suggest that Ki-67 in heterogeneous breast carcinoma is evaluated and reported separately for the distinguishable tumor components.

Keywords

Evaluation, heterogeneous breast carcinoma, Ki-67 index