C22.4
BillableOther sarcomas of liver
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C22.4 an HCC code?
Yes. C22.4 maps to Lung and Other Severe Cancers under the CMS-HCC V28 risk adjustment model (and Lung and Other Severe 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 C22.4
For C22.4 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 C22.4 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C22.4 is the ICD-10-CM diagnosis code for other sarcomas of liver. A group of rare cancers of the liver that develop from connective tissue or muscle cells, excluding angiosarcoma. These are aggressive tumors with poor prognosis. C22.4 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of digestive organs (c15-c26).
Under the CMS-HCC V28 risk adjustment model, C22.4 maps to Lung and Other Severe Cancers (HCC 20) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, C22.4 mapped to the same category but with a base RAF weight of 0.973 — V28 recalibrated weights across the entire model. 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.
Confirm histological type of sarcoma (leiomyosarcoma, fibrosarcoma, etc.) in documentation. Because C22.4 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 C22.4 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Confirm histological type of sarcoma (leiomyosarcoma, fibrosarcoma, etc.) in documentation
- •Ensure angiosarcoma is excluded; if present, use C22.3 instead
Clinical Significance
Other sarcomas of the liver encompasses rare malignancies arising from non-vascular connective tissue within the liver, including leiomyosarcoma, fibrosarcoma, and undifferentiated embryonal sarcoma. These tumors are exceptionally rare, each requiring specific pathological confirmation and treatment planning. Their aggressive nature and rarity make them challenging to manage, often requiring referral to specialized centers with experience in hepatic sarcomas.
Documentation Requirements
- ✓Pathological confirmation of sarcoma subtype (leiomyosarcoma, fibrosarcoma, undifferentiated sarcoma, etc.)
- ✓Confirmation that angiosarcoma has been excluded (which has its own code C22.3)
- ✓Stage of disease and extent of hepatic involvement
- ✓Any known predisposing conditions or prior radiation exposure
- ✓Treatment approach