C91.92
BillableLymphoid leukemia, unspecified, in relapse
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C91.92 an HCC code?
Yes. C91.92 maps to Bladder, Colorectal, and Other Cancers under the CMS-HCC V28 risk adjustment model (and Lymphoma and Other Cancers under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for C91.92
For C91.92to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed C91.92 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C91.92 is the ICD-10-CM diagnosis code for lymphoid leukemia, unspecified, in relapse. A type of blood cancer affecting lymphoid cells that has returned after a period of remission. C91.92 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of lymphoid, hematopoietic and related tissue (c81-c96).
Under the CMS-HCC V28 risk adjustment model, C91.92 maps to Bladder, Colorectal, and Other Cancers (HCC 22) with a community, non-dual, aged base RAF weight of 0.363. Under the older CMS-HCC V24 model, C91.92 maps to Lymphoma and Other Cancers (HCC 10) with a community, non-dual, aged base RAF weight of 0.675. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
This code indicates the cancer has recurred after previously being in remission. Because C91.92 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for C91.92 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code indicates the cancer has recurred after previously being in remission
- •Ensure documentation distinguishes between initial diagnosis and relapse status
Clinical Significance
Lymphoid leukemia, unspecified, in relapse indicates recurrence of an unspecified lymphoid leukemia after remission. The relapse designation implies a documented history of prior treatment, remission, and now recurrent disease. This code's lack of specificity is a concern at the relapse stage, as the subtype should typically be well-established by this point in the disease course.
Documentation Requirements
- ✓Documentation must confirm prior remission and current relapse with supporting evidence.
- ✓At relapse, updated diagnostic studies (flow cytometry, cytogenetics, molecular testing) should be documented and may allow reclassification to a more specific code.
- ✓Treatment history, duration of prior remission, and relapse-associated findings should be recorded.
Commonly Confused Codes
- •Specific relapse codes are strongly preferred: C91.12 (B-CLL in relapse), C91.02 (ALL in relapse), C91.42 (HCL in relapse).
- •C91.Z2 (other lymphoid leukemia in relapse) is for specified types not elsewhere classified.
- •C91.90 (lymphoid leukemia, unspecified, not in remission) should not be used interchangeably with relapse status.