ARID1A and neoplasm: In IBC, the top mutated genes in the samples from the primary tumor samples were TP53 (11/19, 58%) and PIK3CA (4/19, 21%), and in the metastatic samples TP53 (11/17, 65%), PIK3CA (5/17, 29%), then ARID1A and GATA3 (2/17, 12%).