C7B.00
BillableSecondary carcinoid tumors, unspecified site
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C7B.00 an HCC code?
Yes. C7B.00 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.00
For C7B.00to 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.00 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C7B.00 is the ICD-10-CM diagnosis code for secondary carcinoid tumors, unspecified site. This code describes cancer that started as a carcinoid tumor (a slow-growing neuroendocrine cancer) in one part of the body and has spread to other sites, but the original location is not specified. Carcinoid tumors produce hormones that can cause various symptoms throughout the body. C7B.00 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.00 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.00 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 code only when the primary carcinoid tumor site is unknown or not documented; if the primary site is known, code the primary carcinoid tumor first with a secondary malignancy code. Because C7B.00 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.00 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code only when the primary carcinoid tumor site is unknown or not documented; if the primary site is known, code the primary carcinoid tumor first with a secondary malignancy code
- •Carcinoid tumors are neuroendocrine neoplasms; ensure documentation specifies this is a secondary/metastatic carcinoid rather than a primary tumor at an unspecified site
Clinical Significance
Secondary carcinoid tumors at an unspecified site indicates that a carcinoid tumor has metastasized but the specific metastatic site is not documented. This represents advanced Stage IV neuroendocrine disease requiring systemic therapy and significantly impacts patient morbidity and mortality. The metastatic designation dramatically escalates resource utilization and treatment complexity compared to localized carcinoid disease.
Documentation Requirements
- ✓Documentation confirming metastatic/secondary carcinoid disease (not primary)
- ✓Identification and coding of the primary carcinoid tumor site separately (C7A codes)
- ✓Imaging studies (CT, MRI, octreotide scan, or DOTATATE PET) documenting metastatic sites
- ✓Query provider for specific metastatic site(s) to enable more specific coding
- ✓Treatment approach for metastatic disease (systemic therapy, liver-directed therapy, somatostatin analogs)
- ✓Presence or absence of carcinoid syndrome
Commonly Confused Codes
- •C7B.01-C7B.09 — Site-specific secondary carcinoid codes: Use these when the metastatic site is documented (lymph nodes, liver, bone, peritoneum)
- •C7A codes — Primary malignant carcinoid tumors: C7A codes are for the primary tumor; C7B codes are exclusively for metastatic sites
- •C80.0 — Disseminated malignant neoplasm, unspecified: Use when widespread cancer of unknown primary type is present, not specifically carcinoid