C7A.021
BillableMalignant carcinoid tumor of the cecum
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C7A.021 an HCC code?
Yes. C7A.021 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.021
For C7A.021 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.021 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C7A.021 is the ICD-10-CM diagnosis code for malignant carcinoid tumor of the cecum. A rare cancer that develops in hormone-producing cells of the cecum, which is the first part of the large intestine. C7A.021 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.021 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.021 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 cecum is located at the junction where the small intestine meets the large intestine on the right side. Because C7A.021 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.021 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •The cecum is located at the junction where the small intestine meets the large intestine on the right side
- •Ensure documentation distinguishes between cecal carcinoid and other cecal malignancies
Clinical Significance
Malignant carcinoid tumor of the cecum is a neuroendocrine neoplasm arising at the junction of the small and large intestine. Cecal carcinoids tend to be larger at diagnosis compared to appendiceal carcinoids and have a higher risk of metastatic disease. They may present with right lower quadrant pain, palpable mass, or gastrointestinal bleeding, and often require right hemicolectomy.
Documentation Requirements
- ✓Pathological confirmation of neuroendocrine differentiation with malignant grade
- ✓Tumor size, depth of invasion, and lymphovascular involvement
- ✓Ki-67 index and mitotic rate for WHO grading
- ✓Staging — regional lymph node involvement and distant metastases
- ✓Colonoscopy or imaging findings confirming cecal location
- ✓Surgical approach and margin status
Commonly Confused Codes
- •C18.0 — Primary malignant neoplasm of cecum; cecal adenocarcinoma is far more common than cecal carcinoid
- •C7A.020 — Malignant carcinoid tumor of appendix; the appendix attaches to the cecum but has its own code
- •C7A.022 — Malignant carcinoid tumor of ascending colon; the cecum is proximal to the ascending colon
- •D3A.021 — Benign carcinoid tumor of cecum; verify malignant behavior before assigning C7A.021