biostudies-literatureMuendlein AEuropean Regional Development Fund6761https://www.ebi.ac.uk/biostudies/studies/S-EPMC7990915biostudies-literatureUnknown11(1)Mutational analysis of circulating tumour (ct) DNA holds promise as an effective tool to predict the course of metastatic breast cancer (MBC). In the present study we used targeted next generation sequencing of ctDNA to evaluate the impact of cancer driven mutations on the prognosis of MBC. The study included 59 oestrogen receptor-positive (ER+), HER2-negative MBC patients. Sequencing analysis was performed in ESR1, PIK3CA, ERBB2, PTEN, TP53, KRAS, HRAS, NRAS, and AR. At baseline, patients started receiving either chemotherapy (34%; n = 20) or cyclin-dependent kinase 4/6 inhibitor therapy in combination with endocrine therapy (CDK4/6i+ET; 66%; n = 39). Overall, 64.4% (n = 38) of the patients carried at least one pathogenic or likely-pathogenic mutation. Number of ctDNA mutations was signifScientific reportsSignificant impact of circulating tumour DNA mutations on survival in metastatic breast cancer patients.PMC7990915ABH055Dechow TGaumann ADecker TLeiherer AWinder TMuendlein AGeiger KNonnenbroich CGaenger SMayer FDrexel HJagla WfalseSignificant impact of circulating tumour DNA mutations on survival in metastatic breast cancer patients.Mutational analysis of circulating tumour (ct) DNA holds promise as an effective tool to predict the course of metastatic breast cancer (MBC). In the present study we used targeted next generation sequencing of ctDNA to evaluate the impact of cancer driven mutations on the prognosis of MBC. The study included 59 oestrogen receptor-positive (ER+), HER2-negative MBC patients. Sequencing analysis was performed in ESR1, PIK3CA, ERBB2, PTEN, TP53, KRAS, HRAS, NRAS, and AR. At baseline, patients started receiving either chemotherapy (34%; n = 20) or cyclin-dependent kinase 4/6 inhibitor therapy in combination with endocrine therapy (CDK4/6i+ET; 66%; n = 39). Overall, 64.4% (n = 38) of the patients carried at least one pathogenic or likely-pathogenic mutation. Number of ctDNA mutations was signif2021-01-01T00:00:00Z2021 Mar2025-04-04T12:31:59.734Z2025-04-04T12:31:59.734ZS-EPMC79909153376264710.1038/s41598-021-86238-7