Is C91.4 a billable ICD-10-CM code?

No. C91.4 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does C91.4 sit in the tabular list?

Neoplasms (C00-D49), in the block Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96).

C91.4

C91.4 — Hairy cell leukemia

Non-billable headerICD-10-CM

C91.4 is a non-billable header ICD-10-CM code for hairy cell leukemia. It cannot be billed on its own: choose one of the more specific child codes below.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

Leukemic reticuloendotheliosis

Other codes that can never be billed with C91.4

These codes carry an Excludes1 note pointing at C91.4. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading C91.4 alone.

C94Other leukemias of specified cell type
D61.81Pancytopenia
D76Other specified diseases with participation of lymphoreticular and reticulohistiocytic tissue

Risk adjustment

C91.4 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead C91.4

3 child codes. Green means billable.

Related codes at this level

Codes that share C91. If C91.4 is not quite right, the correct code is usually one of these.

Questions about C91.4

Is C91.4 a billable ICD-10-CM code?: No. C91.4 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does C91.4 sit in the tabular list?: Neoplasms (C00-D49), in the block Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96).