D46.20
BillableRefractory anemia with excess of blasts, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D46.20 an HCC code?
Yes. D46.20 maps to Lymphoma and Other Cancers under the CMS-HCC V28 risk adjustment model (and Severe Hematological Disorders 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 D46.20
For D46.20 to 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 D46.20 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D46.20 is the ICD-10-CM diagnosis code for refractory anemia with excess of blasts, unspecified. A bone marrow disorder where red blood cells cannot be produced normally and there is an excess of immature blood cells, but the specific percentage is not documented. D46.20 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes (d37-d48).
Under the CMS-HCC V28 risk adjustment model, D46.20 maps to Lymphoma and Other Cancers (HCC 19) with a community, non-dual, aged base RAF weight of 0.105. Under the older CMS-HCC V24 model, D46.20 maps to Severe Hematological Disorders (HCC 46) with a community, non-dual, aged base RAF weight of 0.666. 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.
Use this code only when the percentage of blasts is not specified. Because D46.20 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 D46.20 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
Clinical Significance
Refractory anemia with excess of blasts, unspecified, represents a higher-risk myelodysplastic syndrome subtype where immature blast cells are elevated in the bone marrow but the specific percentage is not documented. This condition carries a significantly increased risk of transformation to acute myeloid leukemia compared to lower-grade myelodysplastic syndrome subtypes.
Documentation Requirements
- ✓Documentation should include bone marrow biopsy confirming elevated blast percentage, though the specific count is not available for subtyping.
- ✓A provider query should be initiated to determine the exact blast percentage (5-9% for RAEB-1 or 10-19% for RAEB-2) for more specific coding.
- ✓Document cytogenetic findings, transfusion requirements, and disease trajectory.