Abstract P3-01-06: Correlation of disseminated or circulating tumor cells with the OncotypeDX recurrence score

Abstract

Background: New biomarkers continue to emerge to predict the risk of recurrence in women with early stage breast cancer. A high OncotypeDX Recurrence Score (RS)® has been found to be associated with worse disease-free and overall survival in patients with early stage breast cancer. Similarly, circulating tumor cells (CTCs, blood) and disseminated tumor cells (DTCs, bone marrow) have prognostic value in patients with breast cancer. We sought to evaluate the association between high RS and CTCs and DTCs. Methods: We evaluated patients with hormone receptor positive, HER2 negative, node-negative invasive breast cancer from a prospective database from 1/2005 to 1/2017. RS was classified based on the new TAILORx study cutoff points as low (<11), intermediate (11-25), and high (>25). CTCs were assessed using CellSearch. For DTCs cytospin specimens of bone marrow aspirates, enriched for epithelial cells by density gradient separation, were immunostained using a pancytokeratin cocktail of antibodies, including AE1/AE3, CAM5.2, MNF116, cytokeratin 8 (CK8), and CK18. CTCs and DTCs were considered to be positive if one or more CTCs or DTCs were identified, respectively. Chi square analyses were utilized to evaluate for a relationship between OncotypeDX RS and CTCs or DTCs. Statistical analyses were performed in SPSS version 24 with p value <0.05 considered significant. Results: Two hundred and thirty patients meeting the above criteria were identified from a prospective database, of which 106 had OncotypeDX testing results. Of the patients with available OncotypeDX data, 93 patients had CTC results and 60 patients had DTC results. CTCs were detected in the blood of 18/93 (19.4%) patients, while DTCs were detected in the bone marrow of 20/60 (33.3%) patients. Patients with high RS were not more likely to have CTCs as compared with patients who had low or intermediate RS (16.7% vs 19.8%, p=0.801). Similarly, high RS was not associated with the detection of DTCs, with DTCs present in 44.4% of patients with high RS, compared with 31.4% of patients with low or intermediate RS (p=0.443). In the subgroup of patients ≤50 years of age no associations were found between high RS and CTCs (p=0.720) or DTCs (p=0.151). Conclusions: High OncotypeDX RS did not correlate with CTCs in the blood or DTCs in the bone marrow in our study. Citation Format: Tevis SE, Hall C, Meas S, Hwang R, Lucci A. Correlation of disseminated or circulating tumor cells with the OncotypeDX recurrence score [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-01-06.

Prognostic and Predictive Value of Circulating and Disseminated Tumor Cells in Breast Cancer: A National Cancer Database (NCDB) Analysis

“…23 High-risk individuals may benefit most from the addition of chemotherapy to endocrine therapy, helping clinicians make an evidence-based decision before escalating therapy in certain patients. 15 In one study, a high RS was not significantly associated with the presence of CTCs or DTCs, 24 suggesting that the predictive value of CTCs may be independent of this 21gene assay. Goodman et al also used the NCDB to show that there was a significant association between CTC status with a benefit of radiotherapy in early-stage BC, 25 further emphasizing the potential utility of this biomarker in clinical decisionmaking.…”