2026 ICD-10-CM Diagnosis Code D09.9Carcinoma in situ, unspecified
ICD-10-CM Codes›C00–D49›D00-D09›D09
- Billable — Valid for Submission
- Chronic Condition
D09.9 is a billable ICD-10-CM diagnosis code for carcinoma in situ, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 826 through 830, 843 through 845. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Malignant neoplasm, unspecified.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Adenocarcinoma in situ in villous adenoma
- Carcinoma in situ
- Common bile duct surgical margin, involved by tumor
- Intraepithelial squamous cell carcinoma
- Squamous cell carcinoma in situ
- Surgical bile duct margin involved by carcinoma in situ
- Surgical bile duct margin uninvolved by carcinoma in situ
- Surgical bronchial margin involved by squamous cell carcinoma in situ
- Surgical bronchial margin involved by tumor
- Surgical common bile duct margin involved by in situ carcinoma
- Surgical common bile duct margin uninvolved by in situ carcinoma
- Surgical cystic duct margin involved by in situ carcinoma
- Surgical cystic duct margin uninvolved by in situ carcinoma
- Surgical deep margin involved by in situ carcinoma
- Surgical deep margin uninvolved by in situ carcinoma
- Surgical distal margin involved by in situ carcinoma
- Surgical distal margin involved by in situ carcinoma/adenoma
- Surgical distal margin involved by tumor
- Surgical distal margin uninvolved by in situ carcinoma
- Surgical distal margin uninvolved by in situ carcinoma/adenoma
- Surgical distal mucosal margin involved by in situ carcinoma
- Surgical distal mucosal margin uninvolved by in situ carcinoma
- Surgical ductal margin uninvolved by in situ carcinoma
- Surgical lateral margin involved by in situ carcinoma
- Surgical lateral margin involved by in situ carcinoma/adenoma
- Surgical lateral margin uninvolved by in situ carcinoma
- Surgical lateral margin involved by tumor
- Surgical margin involved by in situ carcinoma
- Surgical margin involved by in situ carcinoma/adenoma
- Surgical margin uninvolved by in situ carcinoma
- Surgical margin uninvolved by in situ carcinoma/adenoma
- Surgical mucosal margin involved by in situ carcinoma
- Surgical mucosal margin uninvolved by in situ carcinoma
- Surgical pancreatic duct margin involved by in situ carcinoma
- Surgical pancreatic duct margin uninvolved by in situ carcinoma
- Surgical pancreatic parenchymal margin involved by in situ carcinoma
- Surgical parenchymal margin finding
- Surgical proximal margin involved by in situ carcinoma
- Surgical proximal margin involved by in situ carcinoma/adenoma
- Surgical proximal margin uninvolved by in situ carcinoma
- Surgical proximal margin uninvolved by in situ carcinoma/adenoma
- Surgical proximal mucosal margin involved by in situ carcinoma
- Surgical proximal mucosal margin uninvolved by in situ carcinoma
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Carcinoma in Situ
a lesion with cytological characteristics associated with invasive carcinoma but the tumor cells are confined to the epithelium of origin, without invasion of the basement membrane.
Table of NeoplasmsClinical
Patient EducationClinical
Cancer
Cancer is not just one disease but many diseases. Cancer begins in your cells, which are the building blocks of your body. Usually, your body forms new cells as needed, replacing old cells that die. Sometimes this process goes wrong. New cells grow even when you don't need them, and old cells don't die when they should.
The full article covers:
- What is cancer?
- What are the types of cancer?
- How does cancer develop?
- What are the symptoms of cancer?
- How is cancer diagnosed?
- What are the treatments for cancer?
- Can cancer be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert D09.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About D09.9Overview
Is D09.9 (Carcinoma in situ of other and unspecified sites) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report carcinoma in situ, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does D09.9 group to?
When carcinoma in situ, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 826, 827, 828, 829, 830, 843, 844, 845, with relative weights from 0.8516 to 4.6778 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of D09.9?
Under the General Equivalence Mappings, carcinoma in situ, unspecified converts to ICD-9-CM 234.9 (ca in situ NOS). The mapping is a direct match.
Footnotes
[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:
- The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
- The condition places limitations on self-care, independent living, and social interactions.
