C91.Z0 Other lymphoid leukemia not having achieved remission

ICD-10-CM Diagnosis Code C91.Z0: Other lymphoid leukemia not having achieved remission

ICD-10-CM code C91.Z0 is assigned the preferred name "Other lymphoid leukemia not having achieved remission" and is classified as a neoplastic process. The code appears in Medicare billing articles and medical coding references alongside related codes for remission and relapse. The supplied sources establish the code's designation and context but do not provide clinical criteria or coverage guarantees. 2 4 5

Plain-language overview

Code C91.Z0 carries the preferred name "Other lymphoid leukemia not having achieved remission" and has the semantic type of "Neoplastic Process" according to the EVS Explore portal. 4

What this code represents

Code C91.Z0 is listed alongside C91.Z1 for remission and C91.Z2 for relapse within the same coding framework for other lymphoid leukemia. 2 5

A university database includes "Other lymphoid leukemia not having achieved remission" in a list that also contains acute, chronic, subacute, and unspecified lymphoid leukemia not having achieved remission. 1

Documentation considerations

Code C91.Z0 is listed in a Medicare article titled "MolDX: Minimal Residual Disease Testing for Hematologic Cancers," which also includes the related remission and relapse codes. 2

Coverage and utilization context

The inclusion of C91.Z0 in a Medicare billing article for minimal residual disease testing provides operational context, but the cited sources do not confirm that this inclusion guarantees coverage for any specific service. 2

What the sources add

The EVS Explore portal provides the semantic classification of C91.Z0 as a neoplastic process, while a Medicare billing article places the same code within an operational framework for hematologic cancer testing. 2 4

A university genetics database lists the phrase "Other lymphoid leukemia not having achieved remission" among various lymphoid leukemia states, whereas the EVS Explore portal explicitly assigns this phrase to code C91.Z0. 1 4

Questions to verify

The cited sources do not establish the specific clinical criteria or laboratory thresholds that a clinician uses to determine that other lymphoid leukemia has not achieved remission. 2 4

Sources

1. Phecode 204 · Cancer PRSweb — csg.sph.umich.edu; accessed 2026-07-25.
2. Article - Billing and Coding: MolDX: Minimal Residual Disease Testing for Hematologic Cancers (A58996) — cms.gov; accessed 2026-07-25.
3. Article - Response to Comments: MolDX: Next Generation Sequencing Lab-Developed Tests for Myeloid Malignancies and Suspected Myeloid Malignancies (A57894) — cms.gov; accessed 2026-07-25.
4. EVS Explore — evsexplore.semantics.cancer.gov; accessed 2026-07-25.
5. C91.Z - Other lymphoid leukemia | ICD-10-CM — unboundmedicine.com; accessed 2026-07-25.