2026 ICD-10-CM Diagnosis Code D42.0Neoplasm of uncertain behavior of cerebral meninges

ICD-10-CM Codes›C00–D49›D37-D48›D42

ICD-10-CM D42.0
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

D42.0 is a billable ICD-10-CM diagnosis code for neoplasm of uncertain behavior of cerebral meninges. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as atypical meningioma of brain meninges. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neoplasms of unspecified nature or uncertain behavior.

Code Identity

ICD-10-CM Code
D42.0
Billable Status
Yes — Valid for Submission
Code Describes
Neoplasm of uncertain behavior of cerebral meninges
Short Description
Neoplasm of uncertain behavior of cerebral meninges
Same as the full description in the CMS dataset.
Parent Code
D42
Neoplasm of uncertain behavior of meninges

Code Classification

ChapterC00–D49Neoplasms
SectionD37-D48Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
CategoryD42Neoplasm of uncertain behavior of meninges
This CodeD42.0Neoplasm of uncertain behavior of cerebral meninges

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Atypical meningioma of brain meninges
  • Intracranial meningioma
  • Meningioma of uncertain behavior
  • Neoplasm of uncertain behavior of brain meninges
  • Neoplasm of uncertain behavior of meninges

Clinical ClassificationClinical

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

CCSR NEO072
Neoplasms of unspecified nature or uncertain behavior
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Adult Intracranial Meningioma|Adult Brain Meningioma

    an intracranial meningioma that occurs during adulthood.

  • Anaplastic (Malignant) Intracranial Meningioma

    an anaplastic meningioma that arises within the cranial cavity.

  • Benign Intracranial Meningioma|Benign neoplasm of cerebral meninges

    a grade i, slowly growing meningioma within the cranial cavity.

  • Childhood Intracranial Meningioma|Brain Meningioma|Childhood Brain Meningioma

    an intracranial meningioma that occurs during childhood.

  • Intracranial Meningioma

    a meningioma that arises within the cranial cavity.

  • Radiation-Induced Intracranial Meningioma

    a meningioma that arises within the cranial cavity and results from exposure to radiation.

  • Grade 1 Intracranial Meningioma|Benign Intracranial Meningioma|Benign neoplasm of cerebral meninges

    a grade i, slowly growing meningioma within the cranial cavity.

Table of NeoplasmsClinical

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

SiteMalig.
Primary		Malig.
Secondary		Ca
in situ		BenignUncertainUnspec.
arachnoid › cerebralC70.0C79.32–D32.0D42.0D49.7
brain NEC › meningesC70.0C79.32–D32.0D42.0D49.7
cerebrum, cerebral (cortex) (hemisphere) (white matter) › meningesC70.0C79.32–D32.0D42.0D49.7
cranial (fossa, any) › meningesC70.0C79.32–D32.0D42.0D49.7
dura (cranial) (mater) › cerebralC70.0C79.32–D32.0D42.0D49.7
falx (cerebella) (cerebri)C70.0C79.32–D32.0D42.0D49.7
meninges › brainC70.0C79.32–D32.0D42.0D49.7
meninges › cerebralC70.0C79.32–D32.0D42.0D49.7
meninges › cranialC70.0C79.32–D32.0D42.0D49.7
meninges › intracranialC70.0C79.32–D32.0D42.0D49.7
pia mater › cerebralC70.0C79.32–D32.0D42.0D49.7
pia mater › cranialC70.0C79.32–D32.0D42.0D49.7
tentorium (cerebelli)C70.0C79.32–D32.0D42.0D49.7

Patient EducationClinical

Brain Diseases

Your brain is the control center of your body. It controls your thoughts, memory, speech, and movement. It regulates the function of many organs. It's part of your nervous system, which also includes your spinal cord and peripheral nerves. The nervous system sends signals between your brain and the rest of the body.

Read the full article at MedlinePlus

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

Convert D42.0 to ICD-9-CMHistory

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

ICD-9-CM
237.6 Unc behav neo meninges
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 D42.0Overview

Is D42.0 (Neoplasm of uncertain behavior of meninges) a billable code?

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

What is the ICD-9 equivalent of D42.0?

Under the General Equivalence Mappings, neoplasm of uncertain behavior of cerebral meninges converts to ICD-9-CM 237.6 (unc behav neo meninges). 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.