Prior studies evaluating ctDNA profiles in patients with mBC have been restricted in their ability to determine racial differences by small sample sizes with limited numbers of Black patients.34,35,36,37,38 GATA3 is a transcription factor involved in the differentiation of breast epithelial cells, and GATA3 alterations have been found in approximately 10% of breast cancers.39,40 Patients with lower levels of intact GATA3 have poorly differentiated tumors, larger tumor size, and higher histologic grades.41,42 There is no current treatment targeting GATA3 alterations. Here, GATA3 is linked to breast cancer.