2026 ICD-10-CM Diagnosis Code D00.00Carcinoma in situ of oral cavity, unspecified site

ICD-10-CM CodesC00–D49D00-D09D00

ICD-10-CM D00.00
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

D00.00 is a billable ICD-10-CM diagnosis code for carcinoma in situ of oral cavity, unspecified site. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 146 through 148. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Head and neck cancers - lip and oral cavity.

Code Identity

ICD-10-CM Code
D00.00
Billable Status
Yes — Valid for Submission
Code Describes
Carcinoma in situ of oral cavity, unspecified site
Short Description
Carcinoma in situ of oral cavity, unspecified site
Same as the full description in the CMS dataset.
Parent Code
Carcinoma in situ of lip, oral cavity and pharynx

Code Classification

ChapterC00–D49Neoplasms
SectionD00-D09In situ neoplasms
CategoryD00Carcinoma in situ of oral cavity, esophagus and stomach
This CodeD00.00Carcinoma in situ of oral cavity, unspecified site

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Carcinoma in situ of floor of mouth
  • Carcinoma in situ of inferior aspect of palate
  • Carcinoma in situ of major salivary gland
  • Carcinoma in situ of minor salivary gland
  • Carcinoma in situ of mouth
  • Carcinoma in situ of oral cavity
  • Carcinoma in situ of oral cavity, lips, salivary glands
  • Carcinoma in situ of palate
  • Carcinoma in situ of parotid gland
  • Carcinoma in situ of retromolar area
  • Carcinoma in situ of salivary gland
  • Carcinoma in situ of salivary gland duct
  • Carcinoma in situ of sublingual gland
  • Carcinoma in situ of submaxillary gland
  • Carcinoma in situ of vestibule of mouth
  • Neoplasm of minor salivary gland
  • Neoplasm of oral cavity and lip and salivary gland
  • Neoplasm of retromolar area
  • Neoplasm of salivary gland duct

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO002
Head and neck cancers - lip and oral cavity
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Cleft Palate

    congenital fissure of the soft and/or hard palate, due to faulty fusion.
  • Palatal Obturators

    appliances that close a cleft or fissure of the palate.
  • Palate

    the structure that forms the roof of the mouth. it consists of the anterior hard palate (palate, hard) and the posterior soft palate (palate, soft).
  • Palate, Hard

    the anteriorly located rigid section of the palate.
  • Palate, Soft

    a movable fold suspended from the posterior border of the hard palate. the uvula hangs from the middle of the lower border.
  • Submandibular Gland

    one of two salivary glands in the neck, located in the space bound by the two bellies of the digastric muscle and the angle of the mandible. it discharges through the submandibular duct. the secretory units are predominantly serous although a few mucous alveoli, some with serous demilunes, occur. (stedman, 25th ed)
  • Submandibular Gland Diseases

    diseases involving the submandibular gland.
  • Submandibular Gland Neoplasms

    new abnormal growth of tissue in the submandibular gland.

Table of NeoplasmsClinical

Anatomical sites in the Table of Neoplasms that reference this code family.

SiteMalig.
Primary
Malig.
Secondary
Ca
in situ
BenignUncertainUnspec.
book-leaf (mouth)C06.89C79.89D00.00D10.39D37.09D49.0
buccal (cavity)C06.9C79.89D00.00D10.39D37.09D49.0
cavityC06.9C79.89D00.00D10.30D37.09D49.0
cavity buccalC06.9C79.89D00.00D10.30D37.09D49.0
cavity oralC06.9C79.89D00.00D10.30D37.09D49.0
junction hard and soft palateC05.9C79.89D00.00D10.39D37.09D49.0
mouthC06.9C79.89D00.00D10.30D37.09D49.0
mouth roofC05.9C79.89D00.00D10.39D37.09D49.0
mouth specified part NECC06.89C79.89D00.00D10.39D37.09D49.0
mouth vestibuleC06.1C79.89D00.00D10.39D37.09D49.0
oral (cavity)C06.9C79.89D00.00D10.30D37.09D49.0
oral (cavity) ill-definedC14.8C79.89D00.00D10.30D37.09D49.0
palateC05.9C79.89D00.00D10.39D37.09D49.0
palate junction of hard and soft palateC05.9C79.89D00.00D10.39D37.09D49.0
palatoglossal archC09.1C79.89D00.00D10.5D37.09D49.0
palatopharyngeal archC09.1C79.89D00.00D10.5D37.09D49.0
parotid (duct) (gland)C07C79.89D00.00D11.0D37.030D49.0
retromolar (area) (triangle) (trigone)C06.2C79.89D00.00D10.39D37.09D49.0
salivary gland or duct (major)C08.9C79.89D00.00D11.9D37.039D49.0
salivary gland or duct (major) minor NECC06.9C79.89D00.00D10.39D37.04D49.0
salivary gland or duct (major) parotidC07C79.89D00.00D11.0D37.030D49.0
salivary gland or duct (major) pluriglandularC08.9C79.89D00.00D11.9D37.039D49.0
salivary gland or duct (major) sublingualC08.1C79.89D00.00D11.7D37.031D49.0
salivary gland or duct (major) submandibularC08.0C79.89D00.00D11.7D37.032D49.0
salivary gland or duct (major) submaxillaryC08.0C79.89D00.00D11.7D37.032D49.0
Stensen's ductC07C79.89D00.00D11.0D37.030D49.0
sublingual gland or ductC08.1C79.89D00.00D11.7D37.031D49.0
submandibular glandC08.0C79.89D00.00D11.7D37.032D49.0
submaxillary gland or ductC08.0C79.89D00.00D11.7D37.032D49.0
vestibuleC06.1C79.89D00.00D10.39D37.09D49.0
vestibule mouthC06.1C79.89D00.00D10.39D37.09D49.0
Wharton's ductC08.0C79.89D00.00D11.7D37.032D49.0

Patient EducationClinical

Oral Cancer

Oral cancer is cancer of the mouth. It is a type of head and neck cancer. Most oral cancers are squamous cell cancers. They begin in the flat cells that cover the surfaces of your mouth, tongue, and lips. The cancer cells may spread into deeper tissue as the cancer grows.

The full article covers:

  • What is oral cancer?
  • Who is more likely to develop oral cancer?
  • What are the symptoms of oral cancer?
  • How is oral cancer diagnosed?
  • What are the treatments for oral cancer?
  • Can oral cancer be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert D00.00 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
230.0 Ca in situ oral cav/phar
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About D00.00Overview

Is D00.00 (Carcinoma in situ of lip, oral cavity and pharynx) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report carcinoma in situ of oral cavity, unspecified site on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does D00.00 group to?

When carcinoma in situ of oral cavity, unspecified site is the principal diagnosis on an inpatient stay, it groups to MS-DRG 146, 147, 148, with relative weights from 0.7971 to 2.1174 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of D00.00?

Under the General Equivalence Mappings, carcinoma in situ of oral cavity, unspecified site converts to ICD-9-CM 230.0 (ca in situ oral cav/phar). The mapping is approximate, so confirm the match fits the documentation.

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.