ICDcodes.org
FY2027

C83.7 vs C91

C83.7 and C91 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 C83.7
mature B-cell leukemia Burkitt type (C91.A-)
C83.7

Burkitt lymphoma

Not billable
Chapter 2
Neoplasms
Section
C81-C96
Use when the record says
  • Atypical Burkitt lymphoma
  • Burkitt-like lymphoma
Indexed under
  • Burkitt › lymphoma
  • Burkitt › tumor
  • Lymphoma › Burkitt (of) (malignant)
  • Lymphoma › Burkitt-like (of) (malignant)
  • Burkitt › lymphoma › small noncleaved, diffuse
C91

Lymphoid leukemia

Not billable
Chapter 2
Neoplasms
Section
C81-C96

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