2026 ICD-10-CM Diagnosis Code C45Mesothelioma

ICD-10-CM Codes›C00–D49›C45-C49›C45

ICD-10-CM C45
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C45 is a non-billable ICD-10-CM category code for mesothelioma, so it cannot be submitted on claims. Use a more specific code from this category instead, such as C45.0, C45.1, C45.2, and C45.7.

Code Identity

ICD-10-CM Code
C45
Billable Status
No — Non-Billable Category
Code Describes
Mesothelioma
Short Description
Mesothelioma
Same as the full description in the CMS dataset.
Chapter
C45-C49
Malignant neoplasms of mesothelial and soft tissue

Code Classification

ChapterC00–D49Neoplasms
SectionC45-C49Malignant neoplasms of mesothelial and soft tissue
CategoryC45Mesothelioma
This CodeC45Mesothelioma

Specific Coding for MesotheliomaOverview

Non-specific codes like C45 require more characters. Use one of these billable codes instead:

  • Use C45.0 for Mesothelioma of pleura

  • Use C45.1 for Mesothelioma of peritoneum

  • Use C45.2 for Mesothelioma of pericardium

  • Use C45.7 for Mesothelioma of other sites

  • Use C45.9 for Mesothelioma, unspecified

Clinical InformationClinical

  • Mesothelioma

    a tumor derived from mesothelial tissue (peritoneum, pleura, pericardium). it appears as broad sheets of cells, with some regions containing spindle-shaped, sarcoma-like cells and other regions showing adenomatous patterns. pleural mesotheliomas have been linked to exposure to asbestos. (dorland, 27th ed)

  • Mesothelioma, Cystic

    a peritoneal mesothelioma affecting mainly young females and producing cysts of variable size and number lined by a single layer of benign mesothelial cells. the disease follows a benign course and is compatible with a normal life expectancy, requiring occasionally partial excision or decompression for relief of pain or other symptoms. malignant potential is exceptional. (from holland et al., cancer medicine, 3d ed, p1345)

  • Mesothelioma, Malignant

    a type of mesothelioma with a tendency to metastasize. most tumors originate from either the pleura or peritoneum, tumors may also originate in the pericardium or testicular tissue. it is associated with asbestos exposure. somatic mutations identified in wt1, bcl10, cdkn2a, nf2, and bap1 genes are associated with the malignancy. omim: 156240.

  • Solitary Fibrous Tumor, Pleural

    a rare neoplasm, usually benign, derived from mesenchymal fibroblasts located in the submesothelial lining of the pleura. it spite of its various synonyms, it has no features of mesothelial cells and is not related to malignant mesothelioma or asbestos exposure.

Patient EducationClinical

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.

Read the full article at MedlinePlus

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

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 C45Overview

Is C45 (Mesothelioma) a billable code?

No. This is a category header that groups the codes for mesothelioma, and headers cannot be submitted on claims. Claims for mesothelioma need a more specific code from this category, such as C45.0, C45.1, and C45.2.