C91.Z – Other lymphoid leukemia

ICD-10-CM 2027 diagnosis code · Malignant neoplasms of lymphoid, hematopoietic and related tissue

Non-billable header

ICD-10-CM code C91.Z
Code
C91.Z (claims format: C91Z)
Description
Other lymphoid leukemia
Billable
No – use a more specific code below
Valid for
Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter
2. Neoplasms (C00-D49)
Block
C81-C96 Malignant neoplasms of lymphoid, hematopoietic and related tissue
Parent codes
C91

Billable codes under C91.Z

C91.Z is a header code and cannot be used on claims. Choose the most specific code:

Notes for C91.Z

Applicable to:
  • T-cell large granular lymphocytic leukemia (associated with rheumatoid arthritis)

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

C91 – Lymphoid leukemia

Excludes1 (not coded here):
  • personal history of leukemia (Z85.6)

Block C81-C96

Excludes2 (not included here):
  • Kaposi's sarcoma of lymph nodes (C46.3)
  • secondary and unspecified neoplasm of lymph nodes (C77.-)
  • secondary neoplasm of bone marrow (C79.52)
  • secondary neoplasm of spleen (C78.89)

Index terms for C91.Z

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in C91

Frequently asked questions

What is ICD-10 code C91.Z?

C91.Z is the ICD-10-CM code for other lymphoid leukemia, in the block C81-C96 (Malignant neoplasms of lymphoid, hematopoietic and related tissue).

Is C91.Z a billable code?

No. C91.Z is a header code with more specific child codes; report one of the billable codes listed above.

What category does C91.Z belong to?

It belongs to category C91 – Lymphoid leukemia.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.