C92.1 vs C93
C92.1 and C93 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on C92.1
chronic myelomonocytic leukemia (C93.1-)
C92.1
Chronic myeloid leukemia, BCR/ABL-positive
Not billable
- Chapter 2
- Neoplasms
- Section
- C81-C96
Use when the record says
- Chronic myelogenous leukemia, Philadelphia chromosome (Ph1) positive
- Chronic myelogenous leukemia, t(9;22) (q34;q11)
- Chronic myelogenous leukemia with crisis of blast cells
Indexed under
- Leukemia, leukemic › chronic myelogenous
- Leukemia, leukemic › chronic myeloid, BCR/ABL-positive
C93
Monocytic leukemia
Not billable
- Chapter 2
- Neoplasms
- Section
- C81-C96
Use when the record says
- monocytoid leukemia
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027