What is ICD-10 code D21.4?

D21.4 is the ICD-10-CM diagnosis code for Benign neoplasm of connective and other soft tissue of abdomen. A benign (non-cancerous) tumor of the soft tissues in the abdominal area, such as in the muscles, fat, or connective tissue. It belongs to the ICD-10-CM chapter for neoplasms (c00-d49). D21.4 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. D21.4 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. D21.4 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. D21.4 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 D21.4 map to under V28?

D21.4 has no payable CMS-HCC V28 mapping in the final FY2026 CMS file.

What RAF reference is published for D21.4?

D21.4 has no V28 reference coefficient because the final FY2026 source verifies no payable V28 mapping.

What is the V28 vs V24 difference for D21.4?

D21.4 has verified no payable V28 mapping in the final FY2026 source. Select a historical effective period before making any V24 comparison.

What documentation supports D21.4?

This code does not require laterality specification as the abdomen is a midline structure Document the specific location within the abdomen if possible for clinical clarity D21.4 is not a CMS-HCC V28 payment code in the verified current source, so MEAT is not the payment hook. Documentation still has to support the diagnosis if you report it.

2026 ICD-10-CM D21.4: Benign neoplasm of connective

D21.4 is not a CMS-HCC payment code. MEAT criteria · RAF Calculator · HCC coding software

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Code lookupD21.4

Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Neoplasms (C00-D49) / Benign neoplasms, except benign neuroendocrine tumors (D10-D36)

D21.4

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

Benign neoplasm of connective and other soft tissue of abdomen

A benign (non-cancerous) tumor of the soft tissues in the abdominal area, such as in the muscles, fat, or connective tissue.

Overview Risk Models Code Book Documentation Audit Notes Edition comparison

CMS-HCC V28

N/A

—

Not risk-adjusted for this model/period.

Not mapped

CMS-HCC V24

Historical

Not used for standard CY2026 Medicare Advantage payment. Select a historical period to review V24.

Not used for CY2026 payment

ACA/HHS

N/A

—

Not risk-adjusted for this model/period.

Not mapped

ESRD/PACE

N/A

—

Not risk-adjusted for this model/period.

Not mapped

RXHCC

N/A

—

Not risk-adjusted for this model/period.

Not mapped

Code Book Path

Official

D21Other benign neoplasms of connective and other soft tissue D21.4Benign neoplasm of connective and other soft tissue of abdomen

Inclusion Terms

Official

Benign stromal tumors of abdomen

Excludes 2

Official

No Excludes 2 notes are included in this display for D21.4. Check the code and parent instructions in the Code Book.

Related Codes

Official

D21.0Benign neoplasm of connective and other soft tissue of head, face and neck D21.1Benign neoplasm of connective and other soft tissue of upper limb, including shoulder D21.2Benign neoplasm of connective and other soft tissue of lower limb, including hip D21.3Benign neoplasm of connective and other soft tissue of thorax D21.5Benign neoplasm of connective and other soft tissue of pelvis

Includes

Official

benign neoplasm of blood vesselInherited from D21
benign neoplasm of bursaInherited from D21
benign neoplasm of cartilageInherited from D21
benign neoplasm of fasciaInherited from D21
benign neoplasm of fatInherited from D21
benign neoplasm of ligament, except uterineInherited from D21
benign neoplasm of lymphatic channelInherited from D21
benign neoplasm of muscleInherited from D21
benign neoplasm of synoviaInherited from D21
benign neoplasm of tendon (sheath)Inherited from D21
benign stromal tumorsInherited from D21

Excludes 1

Official

benign neoplasm of articular cartilage (D16.-)Inherited from D21
benign neoplasm of cartilage of larynx (D14.1)Inherited from D21
benign neoplasm of cartilage of nose (D14.0)Inherited from D21
benign neoplasm of connective tissue of breast (D24.-)Inherited from D21
benign neoplasm of peripheral nerves and autonomic nervous system (D36.1-)Inherited from D21
benign neoplasm of peritoneum (D20.1)Inherited from D21
benign neoplasm of retroperitoneum (D20.0)Inherited from D21
benign neoplasm of uterine ligament, any (D28.2)Inherited from D21
benign neoplasm of vascular tissue (D18.-)Inherited from D21
hemangioma (D18.0-)Inherited from D21
lipomatous neoplasm (D17.-)Inherited from D21
lymphangioma (D18.1)Inherited from D21
uterine leiomyoma (D25.-)Inherited from D21

Code First

Official

No Code First sequencing instructions are included in this display for D21.4. Check the code and parent instructions in the Code Book.

Use Additional

Official

No Use Additional Code instructions are included in this display for D21.4. Check the code and parent instructions in the Code Book.

Code Also

Official

No Code Also instructions are included in this display for D21.4. Check the code and parent instructions in the Code Book.

Buddy Documentation Tip

HCC Buddy guidance

This code does not require laterality specification as the abdomen is a midline structure

Document the specific location within the abdomen if possible for clinical clarity

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 D21.4 an HCC code?

No. D21.4 is a billable ICD-10-CM code with no mapping under the CMS-HCC V28 or V24 community payment models, and none under the ESRD, Part D RxHCC, or HHS-HCC models.

Code: D21.4
Description: Benign neoplasm of connective and other soft tissue of abdomen
HCC (V28): No CMS-HCC V28 mapping
RAF reference coefficient: —
Billable: Yes
Payment year: 2026

Coder workflow notes

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This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).

What This Code Means

D21.4 is the ICD-10-CM diagnosis code for benign neoplasm of connective and other soft tissue of abdomen. A benign (non-cancerous) tumor of the soft tissues in the abdominal area, such as in the muscles, fat, or connective tissue. D21.4 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering benign neoplasms, except benign neuroendocrine tumors (d10-d36).

D21.4 is a billable ICD-10-CM code, but the current payload does not show a mapping under the CMS-HCC V28 or V24 community payment models, and none under the ESRD, Part D RxHCC, or HHS-HCC models. Do not assign risk adjustment value from this page when no source-backed mapping is shown; verify the applicable model and payment year.

This code does not require laterality specification as the abdomen is a midline structure.

HCC Buddy maintains structured V28 and V24 mapping, source-labeled coefficient references, and MEAT documentation criteria for D21.4 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•This code does not require laterality specification as the abdomen is a midline structure
•Document the specific location within the abdomen if possible for clinical clarity