Ki-67 and breast cancer prognosis: does it matter if Ki-67 level is examined using preoperative biopsy or postoperative specimen?

Abstract

Purpose This study aimed to identify the association between Ki-67 level and the prognosis of patients with breast cancer, regardless of the timing of Ki-67 testing (using preoperative biopsy vs. postoperative specimen). Methods A total of 4177 patients underwent surgery between January 2008 and December 2016. Immunohistochemical Ki-67 levels, using either preoperative (1673) or postoperative (2831) specimens, were divided into four groups using cutoff points of 10%, 15%, and 20%. Results Groups with higher-Ki-67 levels, in both the pre- and postoperative periods, showed significantly larger tumor size, higher grade, more frequent hormone receptor-negativity and human epidermal growth factor receptor 2 overexpression, and active adjuvant treatments than groups with lower-Ki-67 levels. High-Ki-67 levels were also significantly associated with poor survival, irrespective of the timing of specimen examination. Conclusion Despite the problems associated with Ki-67, Ki-67 level is an important independent prognostic factor, regardless of the timing of Ki-67 testing, i.e., preoperative or postoperative testing.

Conventional and digital Ki67 evaluation and their correlation with molecular prognosis and morphological parameters in luminal breast cancer

“…On one hand, the study conducted by Ahn et al proved significant differences in the Ki67 index between core biopsy and surgical specimens 33 , in contrast with other work 34 which shows significantly concordant results. Nevertheless, a large recent study which included more than 4000 patients and evaluated the differences in the prognostic value of Ki67 between core biopsy and postoperative specimen, concludes that Ki67 is an important prognostic factor regardless of the timing of testing, although it is recommended to analyse this parameter preoperatively 35 . In our study, we decided to use only Ki67 score from biopsies in order to maintain the routine procedure and thus increase the clinical value of our analysis, although acknowledging the above-mentioned bias.…”

Pro-Inflammatory and Anti-Inflammatory Salivary Cytokines in Breast Cancer: Relationship with Clinicopathological Characteristics of the Tumor

“…In our study, the level of IL-1β is elevated at all stages of breast cancer, particularly in the presence of even a single metastasis in the lymph nodes ( Figure 2 ). A significant increase was noted in HER2-positive breast cancer and with a high level of Ki-67 expression, which may be associated with a poor prognosis [ 55 ].…”

Prognostic Value of Salivary Biochemical Indicators in Primary Resectable Breast Cancer

“…Prognostic indicators based on inflammation are mentioned in the literature, including the ratio of neutrophils to lymphocytes, the ratio of lymphocytes to monocytes, the ratio of platelets to lymphocytes, and the ratio of C-reactive protein/albumin [10,13,14]. High levels of Ki-67 have also been significantly associated with poor survival [15]. Several studies have described the use of molecular markers characterizing the cellular pathways involved in tumor growth and spread (p53, RB, PI3K/Akt/mTOR, and Ras/MAPK) [16,17], as well as the tumor immune microenvironment, including tumor lymphoid infiltration (TILs) to determine the prognosis of breast cancer [18][19][20].…”