C83.0 vs C84
C83.0 and C84 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 C83.0
mature T/NK-cell lymphomas (C84.-)
C83.0
Small cell B-cell lymphoma
Not billable
- Chapter 2
- Neoplasms
- Section
- C81-C96
Use when the record says
- Lymphoplasmacytic lymphoma
- Nodal marginal zone lymphoma
- Non-leukemic variant of B-CLL
- Splenic marginal zone lymphoma
Indexed under
- Immunocytoma
- Lymphoma › lymphoplasmacytic (of) (malignant)
- Lymphoma › nodal marginal zone (of) (malignant)
- Lymphoma › non-leukemic variant of B-CLL (of) (malignant)
- Lymphoma › small cell B-cell (of) (malignant)
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