C7A.022
BillableMalignant carcinoid tumor of the ascending colon
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C7A.022 an HCC code?
Yes. C7A.022 maps to Breast, Prostate, Colorectal and Other Cancers and Tumors 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 C7A.022
For C7A.022 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 C7A.022 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C7A.022 is the ICD-10-CM diagnosis code for malignant carcinoid tumor of the ascending colon. A rare cancer that develops in hormone-producing cells of the ascending colon, the first upward section of the large intestine on the right side of the abdomen. C7A.022 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neuroendocrine tumors (c7a).
Under the CMS-HCC V28 risk adjustment model, C7A.022 maps to Breast, Prostate, Colorectal and Other Cancers and Tumors (HCC 21) with a community, non-dual, aged base RAF weight of 0.545. Under the older CMS-HCC V24 model, C7A.022 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.
The ascending colon runs vertically up the right side of the abdomen; distinguish from transverse and descending portions. Because C7A.022 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 C7A.022 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •The ascending colon runs vertically up the right side of the abdomen; distinguish from transverse and descending portions
- •Colonic carcinoid tumors may present with abdominal symptoms or be found incidentally during colonoscopy
Clinical Significance
Malignant carcinoid tumor of the ascending colon is a rare neuroendocrine neoplasm of the right colon. Ascending colon carcinoids are part of the midgut neuroendocrine tumor family and may produce serotonin, potentially causing carcinoid syndrome when liver metastases are present. They tend to be diagnosed at a larger size compared to appendiceal carcinoids and carry a more guarded prognosis.
Documentation Requirements
- ✓Pathological confirmation with immunohistochemistry (synaptophysin, chromogranin A)
- ✓Tumor size and depth of invasion — transmural involvement increases metastatic risk
- ✓Ki-67 index and mitotic rate for WHO grading
- ✓Colonoscopic and imaging findings confirming ascending colon location
- ✓Staging workup — CT, octreotide scan, liver assessment
- ✓Surgical procedure performed and margin status