Metadata record for the manuscript: Circulating tumor DNA dynamics using a standardized multi-gene panel in advanced breast cancer treated with CDK4/6 inhibition and endocrine therapy

Summary This metadata record provides details of the data supporting the claims of the related manuscript: “Circulating tumor DNA dynamics using a standardized multi-gene panel in advanced breast cancer treated with CDK4/6 inhibition and endocrine therapy”. The related study aimed to answer critical questions regarding circulating tumor DNA (ctDNA) levels as predictors of response to anticancer drugs such as which assay or statistical method to use. Specifically, it investigated the hypothesis that a standardised plasma-based sequencing assay that analyses multiple genes simultaneously at baseline and after 4 weeks (cycle 2 day 1 [C2D1]) of CDK4/6i plus ET can identify patients with HR+/HER2-negative advanced disease with different treatment outcomes. Type of data: circulating tumour DNA (ctDNA) Subject of data: Homo sapiens Sample size: 45 Population characteristics: Eligible patients were ≥18 years of age with histologically confirmed HR+/HER2- negative inoperable or metastatic breast cancer treated with a CDK4/6 inhibitor and ET. Recruitment: This is a prospective, single-center study in 45 consecutive patients that fulfilled the inclusion criteria. Date of data collection: May/2016 to June/2019 Data access The ctDNA and clinical data are available in two separate tabs in the Excel spreadsheet “ctDNA and clinical dataset.xlsx”. This spreadsheet is openly available and shared as part of this metadata record. The CDK serie - ctDNA and clinicopathological dataset is not publicly available in order to protect patient privacy. Requests for access to this dataset can be made to the corresponding author. Corresponding author(s) for this study Aleix Prat, MD, PhD, Hospital Clinic of Barcelona,Translational Genomics and Targeted Therapies in Solid Tumors, IDIBAPS, Villarroel 170, 08035, Barcelona, Spain. Email: [e-mail], Telephone number: ([phone]. Study approval The study was performed in accordance with Good Clinical Practice guidelines and the World Medical Association Declaration of Helsinki. The study was approved by the local institutional research ethics committee, and all patients provided written informed consent.