C76.51
BillableMalignant neoplasm of right lower limb
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C76.51 an HCC code?
Yes. C76.51 maps to Melanoma and Other Skin Cancers under the CMS-HCC V28 risk adjustment model (and Breast, Prostate, and Other Cancers and Tumors 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 C76.51
For C76.51 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 C76.51 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C76.51 is the ICD-10-CM diagnosis code for malignant neoplasm of right lower limb. Cancer that has developed in the right leg, thigh, knee, or foot area. C76.51 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of ill-defined, other secondary and unspecified sites (c76-c80).
Under the CMS-HCC V28 risk adjustment model, C76.51 maps to Melanoma and Other Skin Cancers (HCC 23) with a community, non-dual, aged base RAF weight of 0.251. Under the older CMS-HCC V24 model, C76.51 maps to Breast, Prostate, and Other Cancers and Tumors (HCC 12) with a community, non-dual, aged base RAF weight of 0.150. 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.
Ensure documentation clearly specifies 'right' side before assigning this code. Because C76.51 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 C76.51 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Ensure documentation clearly specifies 'right' side before assigning this code
- •This includes malignancies of the right hip, thigh, knee, lower leg, ankle, and foot
Clinical Significance
Malignant neoplasm of the right lower limb specifies cancer in the right thigh, leg, or foot where the tissue of origin is ill-defined. Lower extremity sarcomas (bone and soft tissue) are relatively more common in the lower limbs than upper limbs. Laterality documentation supports surgical planning and radiation targeting.
Documentation Requirements
- ✓Documentation confirming right lower limb malignancy
- ✓Pathology identifying tissue type for more specific coding
- ✓Imaging documenting location (thigh, leg, foot) and tumor extent
- ✓Neurovascular and functional assessment of the right lower extremity
- ✓Treatment plan including limb salvage vs. amputation considerations