2024 ICD-10-CM Diagnosis Code C04.9

Malignant neoplasm of floor of mouth, unspecified

ICD-10-CM Code:
ICD-10 Code for:
Malignant neoplasm of floor of mouth, unspecified
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Code Navigator:

Code Classification

  • Neoplasms
    • Malignant neoplasms of lip, oral cavity and pharynx
      • Malignant neoplasm of floor of mouth

C04.9 is a billable diagnosis code used to specify a medical diagnosis of malignant neoplasm of floor of mouth, unspecified. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

The following anatomical sites found in the Table of Neoplasms reference this diagnosis code given the correct histological behavior: Neoplasm, neoplastic mouth floor or Neoplasm, neoplastic sublingual .

Unspecified diagnosis codes like C04.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Carcinoma of floor of mouth
  • Malignant melanoma of floor of mouth
  • Malignant melanoma of oral cavity
  • Malignant tumor of floor of mouth
  • Primary malignant neoplasm of floor of mouth
  • Squamous cell carcinoma of floor of mouth

Clinical Classification

Convert C04.9 to ICD-9-CM

  • ICD-9-CM Code: 144.9 - Mal neo mouth floor NOS

Table of Neoplasms

This code is referenced in the table of neoplasms by anatomical site. For each site there are six possible code numbers according to whether the neoplasm in question is malignant, benign, in situ, of uncertain behavior, or of unspecified nature. The description of the neoplasm will often indicate which of the six columns is appropriate.

Where such descriptors are not present, the remainder of the Index should be consulted where guidance is given to the appropriate column for each morphological (histological) variety listed. However, the guidance in the Index can be overridden if one of the descriptors mentioned above is present.

Neoplasm, neoplastic Malignant
CaInSitu Benign Uncertain
»Neoplasm, neoplastic
»Neoplasm, neoplastic

Patient Education

Oral Cancer

What is 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.

Most oral cancers are related to tobacco use, heavy alcohol use, or an HPV infection.

Who is more likely to develop oral cancer?

Anyone can get oral cancer, but you are more likely to develop it if you:

  • Use tobacco or drink lots of alcohol. Your risk of developing oral cancer is even higher if you do both.
  • Are male.
  • Are over ago 40.
  • Have HPV.
  • Have a history of head or neck cancer.
  • Get frequent sun exposure (for lip cancer).

What are the symptoms of oral cancer?

The symptoms of oral cancer may include:

  • A white or red patch in your mouth
  • A lip or mouth sore that won't heal
  • Bleeding, pain, or numbness in the lip or mouth
  • Loose teeth or dentures that no longer fit well
  • Problems or pain with swallowing
  • A lump in your neck
  • Ear pain
  • Trouble moving your mouth or jaw
  • Swelling of the jaw
  • A sore throat or feeling that something is caught in the throat

If you have any of these symptoms for more than two weeks, see your health care provider or dentist. Oral cancer can spread quickly, so it's important to find it early.

How is oral cancer diagnosed?

To find out if you have oral cancer, your provider may use:

  • A physical exam of the lips and mouth.
  • An endoscopy.
  • A biopsy or other procedure to collect cells from the lip or oral cavity. The cells are viewed under a microscope to find out if they are abnormal.
  • Imaging tests.

What are the treatments for oral cancer?

The treatments for oral cancer include surgery, radiation therapy, or both. After surgery, some people also need chemotherapy to kill any cancer cells that are left.

Can oral cancer be prevented?

There are steps you can take to help prevent oral cancer:

  • Not smoking
  • Limiting alcohol use or not drinking at all
  • Getting regular dental exams

NIH: National Cancer Institute

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.


[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.