D3A.00
BillableBenign carcinoid tumor of unspecified site
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D3A.00 an HCC code?
Yes. D3A.00 maps to Bladder, Colorectal, and Other Cancers under the CMS-HCC V28 risk adjustment model.
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 D3A.00
For D3A.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 D3A.00 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D3A.00 is the ICD-10-CM diagnosis code for benign carcinoid tumor of unspecified site. A slow-growing benign tumor that produces hormones, located in an unspecified part of the body. D3A.00 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering benign neuroendocrine tumors (d3a).
Under the CMS-HCC V28 risk adjustment model, D3A.00 maps to Bladder, Colorectal, and Other Cancers (HCC 22) with a community, non-dual, aged base RAF weight of 0.363. D3A.00 was not retained as a payment HCC under the older V24 model, so V28 introduced or recategorized it during the 2024–2026 phase-in. 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.
Carcinoid tumors have specific sites; use this code only when the primary site cannot be determined. Because D3A.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 D3A.00 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Carcinoid tumors have specific sites; use this code only when the primary site cannot be determined
- •Review pathology reports carefully to identify the specific anatomical location for more precise coding
Clinical Significance
Benign carcinoid tumor of unspecified site represents a well-differentiated neuroendocrine tumor (NET) with benign behavior whose anatomical origin has not been determined. Carcinoid tumors are slow-growing neoplasms that can produce serotonin and other vasoactive substances, potentially causing carcinoid syndrome. The unspecified site designation suggests incomplete workup or documentation and should prompt investigation to identify the primary site.
Documentation Requirements
- ✓Pathology confirming a well-differentiated neuroendocrine tumor with low proliferative index (Ki-67 less than 3%) and benign behavior.
- ✓Every effort should be made to identify the primary site through imaging (CT, MRI, octreotide scan) and endoscopy.
- ✓Document serum chromogranin A levels, 24-hour urine 5-HIAA if carcinoid syndrome is suspected, and the reason the primary site is unknown.
Commonly Confused Codes
- •D3A.010-D3A.029 are site-specific benign carcinoid codes that should be used when the location is known
- •C7A series codes are for malignant carcinoid tumors
- •E34.0 (carcinoid syndrome) should be coded additionally if the patient has flushing, diarrhea, or bronchospasm from tumor hormone secretion.