Ki‑67 index value and progesterone receptor status can predict prognosis and suitable treatment in node‑negative breast cancer patients with estrogen receptor‑positive and HER2‑negative tumors

Abstract

Gene profiling has identified at least 4 breast cancer subtypes, including Luminal A, Luminal B, HER2-enriched and basal-like, and immunohistochemistry is used as a guide to determine these subtypes. In the present study, patients with ER-positive, HER2-negative and negative nodes were classified into 4 groups according to the PgR and the Ki-67 status and were retrospectively examined. The analysis was based on the clinicopathological findings, and includes the recurrence score (RS) and disease-free survival (DFS) rates. Patients with invasive breast cancer (n=1866) were classified as LA (high PgR/low Ki-67), LB-1 (high PgR/high Ki-67), LB-2 (low PgR/high Ki-67), and LB-3 (low PgR/low Ki-67). In addition, 41 of the cases underwent a 21-gene expression assay. The data revealed that T1 tumors were more prevalent in the LA group and rare in the LB-2 group. Furthermore, nuclear grade 3 and p53 overexpression was revealed to be significantly correlated with LB-2. In terms of prognosis, LA had a significantly more favorable DFS; however, no differences were observed in the LB-3 group. LB-2 had a significantly worse DFS in all cases, and in the cases administered with endocrine therapy alone. Chemotherapy in combination with endocrine therapy was administered to cases with a higher risk of recurrence. In the LB-2 group, there was no difference in the DFS rates between the cases with endocrine therapy and chemo-endocrine therapy. These findings suggest that chemotherapy could improve the DFS in the LB-2 group. In addition, the majority of cases with LA, LB-3 and LB-1 had a RS of ≤25 and the majority of the LB-2 cases had a RS of >25. The patients with LA and LB-3 had a favorable DFS even in the group that received endocrine therapy alone. LB-2 was significantly correlated with a higher degree of malignancy and benefited from chemotherapy. These data suggest that the PgR and the Ki-67 status are effective in predicting prognosis, and for deciding on the most effective treatment strategy in patients with breast cancer.

Neoadjuvant exemestane or exemestane plus docetaxel and cyclophosphamide tailored by clinicopathological response to 12 weeks' exemestane exposure in patients with estrogen receptor‐positive breast cancer: A multicenter, open‐label, phase II study

“…Ki67 is a nuclear antigen expressed during the growth and synthesis phases, but not the resting phase, of the cell cycle. It is therefore a marker of proliferation and has been investigated for its prognostic value in various cancers including gastrointestinal cancer, prostate cancer, and breast cancer …”

“…It is therefore a marker of proliferation and has been investigated for its prognostic value in various cancers including gastrointestinal cancer, 18 prostate cancer, 19 and breast cancer. [20][21][22]…”

21‑gene recurrence score influences the chemotherapy decision for patients with breast cancer of different luminal subtypes

“…Although the 2013 St. Gallen Consensus recommends the usage of multigene signatures, particularly in luminal B disease, for the selection of patients who should receive adjuvant chemotherapy (21), few studies have focused on the role of the 21-gene RS in luminal B breast cancer (32,33). In the prospective Plan B study, 12% of luminal B (Ki-67 ≥20%) tumors were found to be of low risk (RS ≤11) and 48% were found to be of intermediate risk (RS,(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25) according to the 21-gene RS (34).…”

<p>Digital Image Analysis of Ki-67 Stained Tissue Microarrays and Recurrence in Tamoxifen-Treated Breast Cancer Patients</p>

“…17 In this way, proliferation can be used to guide treatment decisions regarding the use of adjuvant chemotherapy. 18 Changes in Ki-67 expression in tumors following short-term neoadjuvant endocrine therapy have also been suggested as a marker of treatment efficacy; thus, breast cancer patients with tumors with high Ki-67 expression after treatment showed lower recurrence-free survival. 19 The association of pre-treatment Ki-67 proliferation index with recurrence risk among women treated with tamoxifen therapy is, however, unclear.…”