Guided example

Rank the case evidence before naming a diagnosis. The greatest weight belongs to marked neutrophilic leukocytosis with cells spanning maturation, a prominent myelocyte population, and absolute basophilia. Eosinophilia and thrombocytosis reinforce the concern. One percent blasts on this smear does not independently assign a disease phase.

A subsequent peripheral-blood assay detects e14a2 BCR::ABL1. That result supports molecular confirmation, while bone marrow morphology and chromosome analysis remain part of integrated diagnostic evaluation. A later validated RT-qPCR report gives BCR::ABL1 on the International Scale (IS) of 0.08%, ABL1 18,500 copies, e14a2, and MR4.0 sensitivity. The International Scale is a standardized reporting scale for compatible standard BCR::ABL1 transcripts. MR3, MR4.0, MR4, and MR4.5 denote 3-, 4-, 4-, and 4.5-log molecular-response depths from the IS baseline: MR3 is at or below 0.1% IS, MR4.0/MR4 at or below 0.01% IS, and MR4.5 at or below 0.0032% IS. Thus 0.08% IS meets MR3; MR4.0 sensitivity can detect about 0.01% IS when assay quality is adequate.

The assay directly measures BCR::ABL1 messenger RNA relative to an internal reference gene; the IS percentage is calculated from that measured ratio and an established conversion factor. It does not by itself assign phase or direct therapy. Reference-gene adequacy and stated sensitivity determine whether an undetected or low result is informative. Release the percentage, transcript, reference-gene result, sensitivity, method, and documented IS calibration or conversion.