2026 ICD-10-CM Diagnosis Code C71.7Malignant neoplasm of brain stem

ICD-10-CM CodesC00–D49C69-C72C71

ICD-10-CM C71.7
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C71.7 is a billable ICD-10-CM diagnosis code for malignant neoplasm of brain stem. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nervous system cancers - brain.

Code Identity

ICD-10-CM Code
C71.7
Billable Status
Yes — Valid for Submission
Code Describes
Malignant neoplasm of brain stem
Short Description
Malignant neoplasm of brain stem
Same as the full description in the CMS dataset.
Parent Code
Malignant neoplasm of brain

Code Classification

ChapterC00–D49Neoplasms
SectionC69-C72Malignant neoplasms of eye, brain and other parts of central nervous system
CategoryC71Malignant neoplasm of brain
This CodeC71.7Malignant neoplasm of brain stem

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Astrocytoma of brain stem
  • Diffuse intrinsic pontine glioma
  • Ependymoma of brain stem
  • Glioma of brainstem
  • Low grade glioma of brainstem
  • Malignant glioma of brainstem
  • Malignant neoplasm of brainstem
  • Malignant neoplasm of cerebral peduncle
  • Malignant neoplasm of medulla oblongata
  • Malignant neoplasm of midbrain
  • Malignant neoplasm of pons
  • Oligodendroglioma of brain
  • Oligodendroglioma of brain stem
  • Primary astrocytoma of brain stem
  • Primary diffuse intrinsic pontine glioma
  • Primary glioblastoma multiforme of brain
  • Primary glioblastoma multiforme of brainstem
  • Primary malignant astrocytoma of brain
  • Primary malignant glioma of brainstem
  • Primary malignant neoplasm of brain stem

Tabular List NotesGuidance

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

Inclusion Terms

  • Malignant neoplasm of fourth cerebral ventricle
  • Infratentorial malignant neoplasm NOS

Clinical ClassificationClinical

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

CCSR NEO048
Nervous system cancers - brain
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Diffuse Intrinsic Pontine Glioma

    a rare, aggressive brain tumor that forms in the glial cells in the pons.

Table of NeoplasmsClinical

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

SiteMalig.
Primary
Malig.
Secondary
Ca
in situ
BenignUncertainUnspec.
basis pedunculiC71.7C79.31D33.1D43.1D49.6
brain NEC choroid plexusC71.7C79.31D33.1D43.1D49.6
brain NEC medulla oblongataC71.7C79.31D33.1D43.1D49.6
brain NEC midbrainC71.7C79.31D33.1D43.1D49.6
brain NEC peduncleC71.7C79.31D33.1D43.1D49.6
brain NEC ponsC71.7C79.31D33.1D43.1D49.6
brain NEC stemC71.7C79.31D33.1D43.1D49.6
brain NEC ventricle (floor) fourthC71.7C79.31D33.1D43.1D49.6
cerebrum, cerebral (cortex) (hemisphere) (white matter) peduncleC71.7C79.31D33.1D43.1D49.6
cerebrum, cerebral (cortex) (hemisphere) (white matter) ventricle fourthC71.7C79.31D33.1D43.1D49.6
ependyma (brain) fourth ventricleC71.7C79.31D33.1D43.1D49.6
medulla oblongataC71.7C79.31D33.1D43.1D49.6
midbrainC71.7C79.31D33.1D43.1D49.6
olive (brain)C71.7C79.31D33.1D43.1D49.6
peduncle, cerebralC71.7C79.31D33.1D43.1D49.6
pons (varolii)C71.7C79.31D33.1D43.1D49.6
pyramid (brain)C71.7C79.31D33.1D43.1D49.6
spine, spinal (column) bulbC71.7C79.31D33.1D43.1D49.6
stem, brainC71.7C79.31D33.1D43.1D49.6
ventricle (cerebral) (floor) (lateral) (third) fourthC71.7C79.31D33.1D43.1D49.6

Patient EducationClinical

Brain Tumors

A brain tumor is a growth of abnormal cells in the tissues of the brain. Brain tumors can be benign, with no cancer cells, or malignant, with cancer cells that grow quickly. Some are primary brain tumors, which start in the brain. Others are metastatic, and they start somewhere else in the body and move to the brain.

Read the full article at MedlinePlus

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

Convert C71.7 to ICD-9-CMHistory

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

ICD-9-CM
191.7 Mal neo brain stem
Exact Match The mapping is direct, with no qualifiers.

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 C71.7Overview

Is C71.7 (Malignant neoplasm of brain) a billable code?

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

What is the ICD-9 equivalent of C71.7?

Under the General Equivalence Mappings, malignant neoplasm of brain stem converts to ICD-9-CM 191.7 (mal neo brain stem). The mapping is a direct match.

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.