Considerable data suggest people with CML achieving a stable deep molecular response (DMR; ≥MR4; 4-log BCR::ABL1 transcript decrease from the standardized baseline, corresponding to a transcript level ≤0.01% on the International Scale) can discontinue therapy, about one-half of whom achieving TFR [34–49]. Here, BCR is linked to chronic myelogenous leukemia, BCR-ABL1 positive.