C7B.8
BillableOther secondary neuroendocrine tumors
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C7B.8 an HCC code?
Yes. C7B.8 maps to Metastatic Cancer and Acute Leukemia under the CMS-HCC V28 risk adjustment model (and Metastatic Cancer and Acute Leukemia 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 C7B.8
For C7B.8 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 C7B.8 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C7B.8 is the ICD-10-CM diagnosis code for other secondary neuroendocrine tumors. Secondary cancers that have spread from neuroendocrine tumors (hormone-producing cancers) to other body sites, not classified as carcinoid or Merkel cell types. C7B.8 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering secondary neuroendocrine tumors (c7b).
Under the CMS-HCC V28 risk adjustment model, C7B.8 maps to Metastatic Cancer and Acute Leukemia (HCC 17) with a community, non-dual, aged base RAF weight of 0.368. Under the older V24 model, C7B.8 mapped to the same category but with a base RAF weight of 2.484 — 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.
Use this as a catch-all for metastatic neuroendocrine tumors not specified elsewhere. Because C7B.8 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 C7B.8 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this as a catch-all for metastatic neuroendocrine tumors not specified elsewhere
- •Always code the primary neuroendocrine tumor site in addition to this secondary site code
Clinical Significance
Other secondary neuroendocrine tumors represents metastatic neuroendocrine cancer that is neither carcinoid nor Merkel cell in origin. This includes metastatic paragangliomas, metastatic mixed neuroendocrine neoplasms, and other rare neuroendocrine tumor types that have spread beyond their primary site. These tumors require specialized oncologic management and carry significant prognostic implications.
Documentation Requirements
- ✓Pathology confirming neuroendocrine differentiation at the metastatic site
- ✓Documentation that the tumor is neither carcinoid nor Merkel cell type
- ✓Primary neuroendocrine tumor site identified and coded separately
- ✓Specific metastatic site(s) documented
- ✓Tumor type classification (paraganglioma, MiNEN, etc.)
- ✓Treatment plan including any targeted therapies