What is ICD-10 code C25.4?

C25.4 is the ICD-10-CM diagnosis code for Malignant neoplasm of endocrine pancreas. Cancer that develops in the endocrine pancreas, the hormone-producing cells (islet cells) that regulate blood sugar and other functions. It belongs to the ICD-10-CM chapter for neoplasms (c00-d49). C25.4 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. C25.4 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. C25.4 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. C25.4 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Which HCC does C25.4 map to under V28?

C25.4 maps to CMS-HCC V28 20 (Lung and Other Severe Cancers). The category number and label come from the CMS-HCC V28 model file for payment year 2026.

What does C25.4 pay in RAF?

C25.4 carries a community, non-dual, aged (CNA) RAF weight of 1.136 under CMS-HCC V28 for payment year 2026. The weight comes from the CMS V28 relative-factor file, not a hand-typed table.

What is the V28 vs V24 difference for C25.4?

CMS phased in the V28 risk adjustment model over payment years 2024 (33%), 2025 (67%), and 2026 (100%), replacing V24. V28 consolidates HCC categories, removes some lower-acuity conditions, and recalibrates RAF weights across the entire model. For C25.4, V28 maps to Lung and Other Severe Cancers at RAF 1.136 while V24 mapped to Lung and Other Severe Cancers at RAF 1.024. Both models can still appear in legacy data and in payer-specific lookback periods.

What documentation supports C25.4?

These are neuroendocrine tumors (NETs) and are distinct from exocrine pancreatic cancers Document whether the tumor is functional (producing hormones) or non-functional for complete clinical picture Because C25.4 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score. See the MEAT criteria checklist at /meat-criteria for what Monitor, Evaluate, Assess, or Treat looks like in a note. MEAT is generic documentation evidence, not a payer-specific rule.

2026 ICD-10-CM C25.4: Malignant neoplasm

C25.4 maps to CMS-HCC V28 20 (RAF 1.136). Documentation must support MEAT. MEAT criteria · RAF calculator · HCC coding software

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Code lookupC25.4Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Neoplasms (C00-D49) / Malignant neoplasms of digestive organs (C15-C26)

C25.4

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Malignant neoplasm of endocrine pancreas

Cancer that develops in the endocrine pancreas, the hormone-producing cells (islet cells) that regulate blood sugar and other functions.

Buddy Insight

Endocrine pancreatic cancers (pancreatic neuroendocrine tumors or PNETs) are biologically and clinically distinct from the more common exocrine pancreatic adenocarcinomas.

CMS-HCC V28

Mapped

HCC 20

Lung and Other Severe Cancers

RAF 1.136

CMS-HCC V24

Mapped

HCC 9

Lung and Other Severe Cancers

RAF 1.024

ACA/HHS

Mapped

HCC 9

HHS-HCC 9

Varies by metal level

ESRD/PACE

Mapped

HCC 9

Lung and Other Severe Cancers

RAF 0.181

RXHCC

Mapped

HCC 20

Cancer, Liver and Intrahepati...

RAF 0.491

Code Book Path

Official

C25Malignant neoplasm of pancreas

C25.4Malignant neoplasm of endocrine pancreas

Inclusion Terms

Official

Malignant neoplasm of islets of Langerhans

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for C25.4 in this effective period.

Related Child Codes

Official

C25.0Malignant neoplasm of head of pancreas

C25.1Malignant neoplasm of body of pancreas

C25.2Malignant neoplasm of tail of pancreas

C25.3Malignant neoplasm of pancreatic duct

C25.7Malignant neoplasm of other parts of pancreas

Includes

Official

ICD-10-CM does not list Includes notes for C25.4 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for C25.4 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for C25.4 in this effective period.

Use Additional

Official

code to identify any functional activity.

Code Also

Official

if applicable exocrine pancreatic insufficiency (K86.81)

Buddy Documentation Tip

HCC Buddy guidance

Pathology confirmation of neuroendocrine tumor (NET) with grade (G1, G2, G3)

Functional status — whether the tumor produces hormones (insulin, gastrin, glucagon, VIP, somatostatin)

Ki-67 proliferation index to determine tumor grade

Current treatment status and stage

MEAT Support

HCC Buddy guidance

Pathology confirmation of neuroendocrine tumor (NET) with grade (G1, G2, G3)

Functional status — whether the tumor produces hormones (insulin, gastrin, glucagon, VIP, somatostatin)

Ki-67 proliferation index to determine tumor grade

Current treatment status and stage

Audit Caution

HCC Buddy guidance

Confusing endocrine (islet cell) tumors with the far more common exocrine ductal adenocarcinomas

Not coding the functional manifestation separately when the tumor produces hormones (e.g., hypoglycemia from insulinoma)

Using unspecified pancreatic cancer code C25.9 when pathology clearly identifies endocrine origin

Failing to report tumor grade which affects prognosis and resource utilization

Common Mistakes

HCC Buddy guidance

C25.0-C25.3 — Other pancreatic cancer sites: Exocrine pancreatic cancers are far more common; verify pathology confirms neuroendocrine histology

D13.7 — Benign neoplasm of endocrine pancreas: Low-grade PNETs can be confused with benign tumors; confirm malignancy

E16.1 — Other hypoglycemia: Functional insulinomas cause hypoglycemia but the underlying tumor requires a neoplasm code

C7A.094 — Malignant carcinoid tumor of foregut: Some pancreatic NETs may be classified as carcinoid tumors depending on pathology

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is C25.4 an HCC code?

Yes. C25.4 (Malignant neoplasm of endocrine pancreas) maps to Lung and Other Severe Cancers under the CMS-HCC V28 risk adjustment model (and Lung and Other Severe Cancers under V24), with a community non-dual aged RAF of 1.136. It is billable for payment year 2026.

Coder answer: C25.4 is billable and maps to V28 HCC 20, Lung and Other Severe Cancers. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.

Code: C25.4
Description: Malignant neoplasm of endocrine pancreas
HCC (V28): HCC 20 — Lung and Other Severe Cancers
RAF: 1.136
Billable: Yes
Payment year: 2026

HCC Category Mapping

V28HCC 20, Lung and Other Severe Cancers

1.136

V24HCC 9, Lung and Other Severe Cancers

1.024

ESRDHCC 9, Lung and Other Severe Cancers

0.181

RxHCCHCC 20, Cancer, Liver and Intrahepatic Bile Duct

0.491

Each model's RAF is its CMS base weight for that model's standard population, so weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. 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.

Work C25.4 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for C25.4

For C25.4 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 C25.4 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

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What This Code Means

C25.4 is the ICD-10-CM diagnosis code for malignant neoplasm of endocrine pancreas. Cancer that develops in the endocrine pancreas, the hormone-producing cells (islet cells) that regulate blood sugar and other functions. C25.4 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering malignant neoplasms of digestive organs (c15-c26).

Under the CMS-HCC V28 risk adjustment model, C25.4 maps to Lung and Other Severe Cancers (HCC 20) with a community, non-dual, aged base RAF weight of 1.136. Under the older V24 model, C25.4 mapped to the same category but with a base RAF weight of 1.024, 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.

These are neuroendocrine tumors (NETs) and are distinct from exocrine pancreatic cancers. Because C25.4 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 C25.4 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•These are neuroendocrine tumors (NETs) and are distinct from exocrine pancreatic cancers
•Document whether the tumor is functional (producing hormones) or non-functional for complete clinical picture

Clinical Significance

Endocrine pancreatic cancers (pancreatic neuroendocrine tumors or PNETs) are biologically and clinically distinct from the more common exocrine pancreatic adenocarcinomas. They generally have a better prognosis but can be functional (hormone-secreting) or non-functional, each requiring different management approaches. Accurate coding distinguishes these patients for appropriate resource allocation.

Documentation Requirements

✓Pathology confirmation of neuroendocrine tumor (NET) with grade (G1, G2, G3)
✓Functional status — whether the tumor produces hormones (insulin, gastrin, glucagon, VIP, somatostatin)
✓Ki-67 proliferation index to determine tumor grade
✓Current treatment status and stage
✓Provider statement confirming endocrine pancreas as the primary site

Use Additional Code

code to identify any functional activity.

Commonly Confused Codes

•C25.0-C25.3: Other pancreatic cancer sites: Exocrine pancreatic cancers are far more common; verify pathology confirms neuroendocrine histology
•D13.7: Benign neoplasm of endocrine pancreas: Low-grade PNETs can be confused with benign tumors; confirm malignancy
•E16.1: Other hypoglycemia: Functional insulinomas cause hypoglycemia but the underlying tumor requires a neoplasm code
•C7A.094: Malignant carcinoid tumor of foregut: Some pancreatic NETs may be classified as carcinoid tumors depending on pathology