C91 — Lymphoid leukemia

Not billable

Is C91 billable?

No — C91 is a non-billable header code. C91 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 27 billable codes beneath C91.

Billable codes under this header

C91 at a glance

Code	C91
Description	Lymphoid leukemia
Billable	No — header code
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Excludes1 — never code together

The conditions below can never be reported together with C91 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

personal history of leukemia (Z85.6)

Excludes2 — not included here — inherited from C81-C96

The conditions below are not part of C91, but a patient may have both at the same time. When documentation supports it, C91 and the excluded code may both be reported.

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)

What codes fall under C91? (9)

How long has C91 existed?

C91 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.

Which codes are confused with C91?

ICD-10-CM declares these codes mutually exclusive with C91 — exactly one of each pair can be correct for a given encounter.