When is ICD-10 code D21 used?

Doctors, hospitals, and insurers may use ICD-10 code D21 when recording other benign neoplasms of connective and other soft tissue in a standardized format. This entry may also act as a broader category that points toward more specific child codes.

Does ICD-10 code D21 confirm a diagnosis?

No. A code helps standardize documentation and claims, but it should not be read as a substitute for a clinician's full assessment.

ICD10

ICD-10 Code D21: Other benign neoplasms of connective and other soft tissue

Name: ICD-10 Code D21: Other benign neoplasms of connective and other soft tissue
Creator: HealthAssure Clinical Team
Published: 2026-05-21T06:03:51.295Z

D21 is an ICD-10 diagnosis entry used to group records related to Other benign neoplasms of connective and other soft tissue. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Neoplasms (C00-D49).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Neoplasms (C00-D49).

When is it used?

May be used when a clinician documents other benign neoplasms of connective and other soft tissue in a patient's medical record.
May appear in hospital records, claims, referrals, and clinical documentation.
This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

A code alone does not explain severity, treatment plan, or outcome.
A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter

2Neoplasms (C00-D49)

block

D10-D36Benign neoplasms, except benign neuroendocrine tumors

currentD10-D36

Official coding notes

Includes

benign neoplasm of blood vessel
benign neoplasm of bursa
benign neoplasm of cartilage
benign neoplasm of fascia
benign neoplasm of fat
benign neoplasm of ligament, except uterine
benign neoplasm of lymphatic channel
benign neoplasm of muscle
benign neoplasm of synovia
benign neoplasm of tendon (sheath)
benign stromal tumors

Excludes1 (do not code together)

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

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Related specialists

OncologistGeneral Physician

Sibling codes

D10Benign neoplasm of mouth and pharynx D11Benign neoplasm of major salivary glands D12Benign neoplasm of colon, rectum, anus and anal canal D13Benign neoplasm of other and ill-defined parts of digestive system D14Benign neoplasm of middle ear and respiratory system D15Benign neoplasm of other and unspecified intrathoracic organs D16Benign neoplasm of bone and articular cartilage D17Benign lipomatous neoplasm D18Hemangioma and lymphangioma, any site D19Benign neoplasm of mesothelial tissue D20Benign neoplasm of soft tissue of retroperitoneum and peritoneum D22Melanocytic nevi D23Other benign neoplasms of skin D24Benign neoplasm of breast D25Leiomyoma of uterus D26Other benign neoplasms of uterus D27Benign neoplasm of ovary D28Benign neoplasm of other and unspecified female genital organs D29Benign neoplasm of male genital organs D30Benign neoplasm of urinary organs D31Benign neoplasm of eye and adnexa D32Benign neoplasm of meninges D33Benign neoplasm of brain and other parts of central nervous system D34Benign neoplasm of thyroid glandbillable D35Benign neoplasm of other and unspecified endocrine glands D36Benign neoplasm of other and unspecified sites

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.

Legacy codes

D21

Replacement codes

D21.0 — Benign neoplasm of connective and other soft tissue of head, face and neckD21.3 — Benign neoplasm of connective and other soft tissue of thoraxD21.4 — Benign neoplasm of connective and other soft tissue of abdomenD21.5 — Benign neoplasm of connective and other soft tissue of pelvisD21.6 — Benign neoplasm of connective and other soft tissue of trunk, unspecifiedD21.9 — Benign neoplasm of connective and other soft tissue, unspecified

Common synonyms

Other benign neoplasms of connective and other soft tissue

Frequently asked questions

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.