Abstract 4742
Background
The gene expression profiling assay OncotypeDx (ODx) prognosticates the risk of estrogen receptor positive (ER+) breast cancer (BC) recurrence and assesses the likely benefit from adjuvant chemotherapy in addition to endocrine therapy. There have been several attempts to develop algorithms that provide similar outcome prediction to the ODx assay with the use of routine clinicopathological characteristics. Ki67 is frequently incorporated into these assessments, although there is no standard cut-off for its use.
Methods
We retrospectively reviewed the electronic medical records of 330 patients with early stage ER+ BC for whom ODx recurrence score (RS) was available. Patients were diagnosed and treated at two specialized cancer centers between 2014 and 2017. Our objective was to determine the ki67’s median differences between ODx risk groups. We used Spearman rho for the correlation between Ki67 and ODx score and used Kruskal-Wallis test for compare medians, pairwaise comparison for the intergroup relations.
Results
Mean age at diagnosis was 57.42 years (range 28-89). Mean tumor diameter was 15.67 mm. 78.9% were intermediate histologic grade and 9.7% patients had lymph node involvement. Median expression of ER and PR were 90% (5-100) and 70% (0-100), respectively. We assessed the correlation between Ki67 and ODx score, with a pearson r:0.31, p < 0.001. The data showed a directly proportional trend between Ki67 and ODx score. Median Ki67 was 20 (1-100). According to ODX RS, 61.5% of tumors were low risk, 30.3% were intermediate risk and, 8.2% were high risk. Median Ki67 within each category group is as follows: low: 15 (IQR:15), intermediate: 20 (IQR:18) and high: 40 (IQR:35), with a statistically significant difference between medians (p < 0.001). In the Pairwise comparison intergroup the data showed: Low-Intermediate (p < 0.05), Low-High (p < 0.001), Intermediate-High (p < 0.001).
Conclusions
The data showed directly proportional trend between Ki67 and ODx score. In our population there is a statistically significant difference between Ki67 medians according to ODx risk groups.
Clinical trial identification
Legal entity responsible for the study
Oncosalud.
Funding
Has not received any funding.
Editorial Acknowledgement
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5349 - Prognostic implications of circulating tumor cells (CTCs) after neoadjuvant chemotherapy for triple negative breast cancer (TNBC)
Presenter: Carolyn Hall
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
2568 - A prediction model for pathological complete response after neoadjuvant chemotherapy of HER2-negative breast cancer patients
Presenter: Lothar Häberle
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
5413 - Evaluation of the MammaTyper® as a molecular predictor for pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) and outcome in patients with different breast cancer (BC) subtypes
Presenter: Peter A. Fasching
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
2260 - Impact of clinical, morphologic and molecular characteristics on response to neoadjuvant systemic therapy (NAST) in metaplastic breast cancer (MpBC)
Presenter: Clinton Yam
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
4722 - Evaluation of Human epidermal growth factor receptor 2 overexpression (HER2+) after administration of neoadjuvant treatment (NAT) and prognostic impact in breast cancer (BC)
Presenter: Duarte Machado
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
4307 - Complete response (CR) to anthracycline-based chemotherapy using magnetic resonance imaging (MRI) predicts high rates of pathologic complete response (pCR) for triple negative breast cancer (TNBC) patients treated preoperatively with anthracycline and taxane-based regimens
Presenter: Maria Marin Alcala
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
5018 - Immunomonitoring of triple negative breast cancer patients undergoing neoadjuvant therapy (GBG89, Geparnuevo trial)
Presenter: Barbara Seliger
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
3203 - Impact of breast cancer subtype on survival after lumpectomy versus mastectomy for early stage invasive breast cancer
Presenter: YU-CHEN Tsai
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
4887 - Survival Outcomes of Dose Dense Neoadjuvant and Adjuvant Chemotherapy in Triple-Negative Breast Cancer Patients – Indian Scenario
Presenter: TANVI Sood
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract
1449 - Prognostic factors associated with pathological complete response in early breast cancer patients undergoing neoadjuvant chemotherapy. The importance of Ki-67 and molecular subtype.
Presenter: Bernardo Rapoport
Session: Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care
Resources:
Abstract