ICD-10-CM > C00-D49 > C81-C96 > C94 > C94.3 C94.3 Mast cell leukemia Non-Billable/Non-Specific Codes C94.30Mast cell leukemia not having achieved remissionC94.31Mast cell leukemia, in remissionC94.32Mast cell leukemia, in relapse