Fig. 2

ESR1 mutation analysis in the loco-regional cohort. a Analysis of matched samples from the loco-regional cohort through the course of the disease: primary tumor, all local recurrences, and advanced metastatic recurrence. Samples are colored according to their mutation type. Red indicates ESR1 Mut. Green indicates ESR1 WT. ESR1 mutations at an allele frequency of > 1% are marked by an asterisk. Dark gray indicates that a tumor was present at this time point but a sample was not available. Lower bars represent the treatments given for each patient prior to the tested local recurrence sample. TAM, tamoxifen, light blue; AI, aromatase inhibitor, blue. b Prevalence of ESR1 mutations in the loco-regional cohort divided according to the type of treatment prior to biopsy. ESR1 mutations at an allele frequency of > 1% are colored with dark red