2026 ICD-10-CM Diagnosis Code D12.1Benign neoplasm of appendix
ICD-10-CM Codes›C00–D49›D10-D36›D12
- Billable — Valid for Submission
- Not Chronic
D12.1 is a billable ICD-10-CM diagnosis code for benign neoplasm of appendix. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 393 through 395. Coders also document this condition as adenomatous polyp of appendix. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Benign neoplasms.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Adenomatous polyp of appendix
- Benign epithelial neoplasm of appendix
- Benign mesenchymoma of appendix
- Benign mesenchymoma of large intestine
- Benign neoplasm of appendix
- Benign tubular adenoma of appendix
- Benign tubular adenoma of large intestine
- Leiomyoma of appendix
- Leiomyoma of large intestine
- Tubular adenoma
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Type 1 Excludes
- benign carcinoid tumor of the appendix D3A.020
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Appendiceal Neoplasms
tumors or cancer of the appendix.Appendix
a worm-like blind tube extension from the cecum.Colon
the segment of large intestine between the cecum and the rectum. it includes the ascending colon; the transverse colon; the descending colon; and the sigmoid colon.
Table of NeoplasmsClinical
Patient EducationClinical
Benign Tumors
Tumors are abnormal growths in your body. They can be either benign or malignant. Benign tumors aren't cancer. Malignant ones are. Benign tumors grow only in one place. They cannot spread or invade other parts of your body. Even so, they can be dangerous if they press on vital organs, such as your brain.
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Convert D12.1 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About D12.1Overview
Is D12.1 (Benign neoplasm of colon, rectum, anus and anal canal) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report benign neoplasm of appendix on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does D12.1 group to?
When benign neoplasm of appendix is the principal diagnosis on an inpatient stay, it groups to MS-DRG 393, 394, 395, with relative weights from 0.6490 to 1.5993 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of D12.1?
Under the General Equivalence Mappings, benign neoplasm of appendix converts to ICD-9-CM 211.3 (benign neoplasm lg bowel). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
