TRPS1 and spindle cell neoplasm: Our study did not include TRPS1, a recently described IHC marker with significantly higher expression in TNBC than GATA3.52, ‐54 However, its expression in phyllodes tumors, myofibroblastoma, and other non-metaplastic spindle cell neoplasms of the breast raises uncertainty regarding its specificity for TNBC.55 Additional studies are required to evaluate the expression of TRPS1 in other mammary and non-mammary origin tumors, and to further elucidate the role of TRPS1 in the workup of metastatic TNBC.