Efficacy of Circulating Tumor Cell Count–Driven vs Clinician-Driven First-line Therapy Choice in Hormone Receptor–Positive, ERBB2-Negative Metastatic Breast Cancer

Abstract

IMPORTANCEThe choice between chemotherapy and endocrine therapy as first-line treatment for hormone receptor-positive, ERBB2 (also known as HER2)-negative metastatic breast cancer is usually based on the presence of clinical features associated with a poor prognosis. In this setting, a high circulating tumor cell (CTC) count (Ն5 CTCs/7.5 mL) is a strong adverse prognostic factor for overall survival and progression-free survival (PFS).OBJECTIVE To compare the efficacy of a clinician-driven treatment choice vs a CTC-driven choice for first-line treatment. INTERVENTIONSIn the CTC arm, patients received chemotherapy or endocrine therapy according to the CTC count (chemotherapy if Ն5 CTCs/7.5 mL; endocrine therapy if <5 CTCs/7.5 mL), whereas in the control arm, the choice was left to the investigator. DESIGN, SETTING, AND PARTICIPANTSIn the STIC CTC randomized, open-label, noninferiority phase 3 trial, participants were randomized to a clinician-driven choice of first-line treatment or a CTC count-driven first-line treatment choice. Eligible participants were premenopausal and postmenopausal women 18 years or older diagnosed with hormone receptor-positive, ERBB2-negative metastatic breast cancer. Data were collected at 17 French cancer centers

The use of liquid biopsy in early breast cancer: clinical evidence and future perspectives

“…Despite the highlighted current analytical and technical limitations of ctDNA detection in early setting, encouraging results are shown by investigations addressing the potential prognostic role of ctDNA detection after primary treatment [27,31] , which suggest considering the detection as a good indicator of MRD. Furthermore, the molecular characterization of ctDNA could act as a versatile, dynamic and not invasive tool of disease characterization that might lead clinicians in the process of treatment choice, anticipating or, in a foreseeable future, even partially replacing the tissue biopsy [46] .…”

“…In summary, notwithstanding the potential of CTCs in monitoring treatment response, there is still no solid evidence about their role in driving the treatment intensity as, on the other hand, has been recently suggested in the metastatic setting [46] .…”

Circulating tumor cells and palbociclib treatment in patients with ER-positive, HER2-negative advanced breast cancer: results from a translational sub-study of the TREnd trial

“…Several clinical trials are currently evaluating strategies of incorporating CTC analysis in informing clinical therapeutic choices [ 30 ]. To date, results are available from the phase III randomized STIC-CTC trial for patients with metastatic ER-positive, HER2-negative breast cancer, which showed the validity of CTC analysis to guide clinical decision-making [ 31 ]. Our results may support the use of CTC counts as a tool to stratify patients in whom greater individualized therapy is currently required during and/or after treatment with palbociclib.…”

Towards Routine Implementation of Liquid Biopsies in Cancer Management: It Is Always Too Early, until Suddenly It Is Too Late

“…Phase III clinical trials evaluating CTC enumeration with clinical parameters have been published in several cancers including the SWOGS0421, SWOG0500, the STIC CTC and the VISNÚ-1 trial [ 8 , 9 , 10 , 11 ]. While the SWOG0421 and VISNÚ-1 studies used CTC counts to identify patients with worse outcomes or to stratify patients for aggressive treatment, SWOG0500 and STIC CTC were the only two trials to date that were actually designed to determine the clinical utility of CTCs.…”

“…While the SWOG0421 and VISNÚ-1 studies used CTC counts to identify patients with worse outcomes or to stratify patients for aggressive treatment, SWOG0500 and STIC CTC were the only two trials to date that were actually designed to determine the clinical utility of CTCs. The STIC CTC trial concluded that CTCs may be a reliable biomarker to guide the choice between first-line chemotherapy or endocrine therapy in metastatic breast cancer [ 10 ].…”