BCR and breast cancer: With this approach, we screened a total of 84 advanced‐phase CML patients, including patients in AP (according to the 4th edition of the WHO classification; n = 21), myeloid BC (n = 38), lymphoid BC (n = 16) and patients with multi‐TKI‐resistant CP harbouring BCR::ABL1 kinase domain mutations (mut‐CP; n = 9).