2026 ICD-10-CM Diagnosis Code C38.0Malignant neoplasm of heart

ICD-10-CM CodesC00–D49C30-C39C38

ICD-10-CM C38.0
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C38.0 is a billable ICD-10-CM diagnosis code for malignant neoplasm of heart. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 314 through 316. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Cardiac cancers.

Code Identity

ICD-10-CM Code
C38.0
Billable Status
Yes — Valid for Submission
Code Describes
Malignant neoplasm of heart
Short Description
Malignant neoplasm of heart
Same as the full description in the CMS dataset.
Parent Code
Malignant neoplasm of heart, mediastinum and pleura

Code Classification

ChapterC00–D49Neoplasms
SectionC30-C39Malignant neoplasms of respiratory and intrathoracic organs
CategoryC38Malignant neoplasm of heart, mediastinum and pleura
This CodeC38.0Malignant neoplasm of heart

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Malignant germ cell neoplasm of heart
  • Malignant germ cell neoplasm of mediastinum
  • Malignant neoplasm of endocardium
  • Malignant neoplasm of heart
  • Malignant neoplasm of myocardium
  • Malignant neoplasm of pericardium
  • Neoplasm of endocardium
  • Neoplasm of epicardium
  • Neoplasm of myocardium
  • Primary angiosarcoma of heart
  • Primary angiosarcoma of thorax
  • Primary angiosarcoma of trunk
  • Primary malignant neoplasm of endocardium
  • Primary malignant neoplasm of epicardium
  • Primary malignant neoplasm of heart
  • Primary malignant neoplasm of myocardium
  • Primary malignant neoplasm of pericardium

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Malignant neoplasm of pericardium

Type 1 Excludes

  • malignant neoplasm of great vessels C49.3

Clinical ClassificationClinical

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

CCSR NEO011
Cardiac cancers
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Endocardium

    the innermost layer of the heart, comprised of endothelial cells.
  • Myocardial Stunning

    prolonged dysfunction of the myocardium after a brief episode of severe ischemia, with gradual return of contractile activity.
  • Myocardium

    the muscle tissue of the heart. it is composed of striated, involuntary muscle cells (myocytes, cardiac) connected to form the contractile pump to generate blood flow.
  • Pericardial Fluid

    watery fluid produced in the serous and visceral pericardium surrounding the surface of the heart.
  • Pericardium

    a conical fibro-serous sac surrounding the heart and the roots of the great vessels (aorta; venae cavae; pulmonary artery). pericardium consists of two sacs: the outer fibrous pericardium and the inner serous pericardium. the latter consists of an outer parietal layer facing the fibrous pericardium, and an inner visceral layer (epicardium) resting next to the heart, and a pericardial cavity between these two layers.

Table of NeoplasmsClinical

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

SiteMalig.
Primary
Malig.
Secondary
Ca
in situ
BenignUncertainUnspec.
atrium, cardiacC38.0C79.89D15.1D48.7D49.89
endocardiumC38.0C79.89D15.1D48.7D49.89
epicardiumC38.0C79.89D15.1D48.7D49.89
heartC38.0C79.89D15.1D48.7D49.89
myocardiumC38.0C79.89D15.1D48.7D49.89
myopericardiumC38.0C79.89D15.1D48.7D49.89
pericardiumC38.0C79.89D15.1D48.7D49.89
ventricle (cerebral) (floor) (lateral) (third) cardiac (left) (right)C38.0C79.89D15.1D48.7D49.89

Patient EducationClinical

Cancer

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The full article covers:

  • What is cancer?
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Read the full article at MedlinePlus

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

Convert C38.0 to ICD-9-CMHistory

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

ICD-9-CM
164.1 Malignant neopl heart
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 C38.0Overview

Is C38.0 (Malignant neoplasm of heart, mediastinum and pleura) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report malignant neoplasm of heart on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C38.0 group to?

When malignant neoplasm of heart is the principal diagnosis on an inpatient stay, it groups to MS-DRG 314, 315, 316, with relative weights from 0.6821 to 2.0852 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C38.0?

Under the General Equivalence Mappings, malignant neoplasm of heart converts to ICD-9-CM 164.1 (malignant neopl heart). 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.