2022 ICD-10-CM Code C45.9

Mesothelioma, unspecified

Version 2021

Valid for Submission

ICD-10:C45.9
Short Description:Mesothelioma, unspecified
Long Description:Mesothelioma, unspecified

Code Classification

  • Neoplasms (C00–D48)
    • Malignant neoplasms of mesothelial and soft tissue (C45-C49)
      • Mesothelioma (C45)

C45.9 is a billable diagnosis code used to specify a medical diagnosis of mesothelioma, unspecified. The code C45.9 is valid during the fiscal year 2022 from October 01, 2021 through September 30, 2022 for the submission of HIPAA-covered transactions.

The ICD-10-CM code C45.9 might also be used to specify conditions or terms like malignant tumor of mesothelial tissue, mesothelioma , neoplasm of mesothelial tissue, pn1: metastasis in the ipsilateral bronchopulmonary and/or hilar lymph node, pn2: metastasis in the subcarinal lymph node , pn3: metastasis in the contralateral mediastinal, internal mammary, or hilar lymph node, etc.

Unspecified diagnosis codes like C45.9 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.

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code C45.9 are found in the index:

Approximate Synonyms

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

Clinical Information

Convert C45.9 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code C45.9 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Mesothelioma

The tissue that lines your lungs, stomach, heart, and other organs is called mesothelium. Mesothelioma, also known as malignant mesothelioma, is cancer of that tissue. It usually starts in the lungs, but can also start in the abdomen or other organs.

Malignant mesothelioma is rare but serious. Most people who get it have worked on jobs where they inhaled asbestos particles. After being exposed to asbestos, it usually takes a long time for the disease to form.

Symptoms include

Sometimes it is hard to tell the difference between malignant mesothelioma and lung cancer. Your doctor uses imaging tests and a biopsy to make the diagnosis. Malignant mesothelioma is often found when it is advanced. This makes it harder to treat. Treatment may include surgery, radiation, chemotherapy, and/or targeted therapy. Targeted therapy uses drugs or other substances that attack specific cancer cells with less harm to normal cells.

NIH: National Cancer Institute


[Learn More in MedlinePlus]

Code History

  • 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 (First year ICD-10-CM implemented into the HIPAA code set)