Can Ki-67 Play a Role in Prediction of Breast Cancer Patients' Response to Neoadjuvant Chemotherapy?

Abstract

Background. Currently the choice of breast cancer therapy is based on prognostic factors. The proliferation marker Ki-67 is used increasingly to determine the method of therapy. The current study analyses the predictive value of Ki-67 in foreseeing breast cancer patients' responses to neoadjuvant chemotherapy. Methods. This study includes patients with invasive breast cancer treated between 2008 and 2013. The clinical response was assessed by correlating Ki-67 to histological examination, mammography, and ultrasonography findings. Results. The average Ki-67 value in our patients collectively (n = 77) is 34.9 ± 24.6%. The average Ki-67 value is the highest with 37.4 ± 24.0% in patients with a pCR. The Ki-67 values do not differ significantly among the 3 groups: pCR versus partial pathological response versus stable disease/progress (P = 0.896). However, Ki-67 values of patients with luminal, Her2 enriched, and basal-like cancers differed significantly from each other. Furthermore, within the group of luminal tumors Ki-67 values of patients with versus without pCR also differed significantly. Conclusion. Our data shows that the Ki-67 value predicts the response to neoadjuvant chemotherapy as a function of the molecular subtype, reflecting the daily routine concerning Ki-67 and its impressing potential and limitation as a predictive marker for neoadjuvant chemotherapy response.

Ki67 Changes Identify Worse Outcomes in Residual Breast Cancer Tumors After Neoadjuvant Chemotherapy

“…A pCR after NAC is strongly associated with favorable long‐term outcomes ; however, patients who do not achieve pCR are a heterogeneous group with diverse prognoses, and unfortunately, until now, no definite biomarker has served as a prognostic discriminator. An even more difficult issue presents in patients with ER‐positive BC, who tend to have low pCR rates and among whom it is highly challenging to distinguish patients with a good prognosis from those with a poor prognosis . Such cases make it fundamental to acquire further tools that are urgently needed to assess potential outcomes.…”

Ki67 expression in invasive breast cancer: the use of tissue microarrays compared with whole tissue sections

“…In two meta-analyses published in 2007 and 2008, high Ki67 expression in both node-positive and node-negative invasive BC showed significantly worse overall and disease-free survival [8, 9]. Additionally, results of a systematic review support the role of Ki67 as a prognostic marker [10] and as an independent predictive factor for neoadjuvant chemotherapy in BC patients [5, 6, 11]. Furthermore, the St. Gallen consensus panel has recommended Ki67 as a marker for the definition of intrinsic BC subtypes to differentiate between luminal A and luminal B subgroups [12, 13].…”

Impact of intratumoural heterogeneity on the assessment of Ki67 expression in breast cancer

“…There is evidence that tumours with higher expression levels of Ki67 respond better to adjuvant chemotherapy than those tumour having low levels of Ki67 [11,12]. Ki67 expression is an independent predictive of neoadjuvant chemotherapy in BC patients [13,14]. as well as the neoadjuvant endocrine therapy in postmenopausal patients.…”