2021 ICD-10-CM Diagnosis Code C71.9

Malignant neoplasm of brain, unspecified

    2016 2017 2018 2019 2020 2021 Billable/Specific Code
  • C71.9 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2021 edition of ICD-10-CM C71.9 became effective on October 1, 2020.
  • This is the American ICD-10-CM version of C71.9 - other international versions of ICD-10 C71.9 may differ.
The following code(s) above C71.9 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to C71.9:
  • C00-D49
    2021 ICD-10-CM Range C00-D49


    • Functional activity
    • All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
    • Morphology [Histology]
    • Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
    • Primary malignant neoplasms overlapping site boundaries
    • A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
    • Malignant neoplasm of ectopic tissue
    • Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).
  • C71
    ICD-10-CM Diagnosis Code C71

    Malignant neoplasm of brain

      2016 2017 2018 2019 2020 2021 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • malignant neoplasm of cranial nerves (C72.2-C72.5)
    • retrobulbar malignant neoplasm (C69.6-)
    Malignant neoplasm of brain
Approximate Synonyms
  • Anaplastic astrocytoma of brain
  • Anaplastic glioma of brain
  • Astrocytoma of brain
  • Astrocytoma of brain, grade 2
  • Astrocytoma of brain, high grade
  • Astrocytoma of brain, low grade
  • Brain cancer, high grade astrocytoma
  • Brain cancer, low grade astrocytoma
  • Cancer brain anaplastic astrocytom malig gliom gr3
  • Cancer of the brain
  • Cancer of the brain metastatic to spinal cord
  • Cancer of the brain, anaplastic glioma
  • Cancer of the brain, astrocytoma
  • Cancer of the brain, astrocytoma, grade 2
  • Cancer of the brain, ependymoma
  • Cancer of the brain, glioblastoma
  • Cancer of the brain, glioblastoma multiforme
  • Cancer of the brain, malignant glioma
  • Cancer of the brain, malignant glioma grade 4
  • Cancer of the brain, malignant glioma low grade
  • Cancer of the brain, oligodendroglioma
  • Ependymoma of brain
  • Glioblastoma multiforme of brain
  • Malignant glioma of brain
  • Malignant glioma of brain, grade 4
  • Malignant glioma of brain, low grade
  • Neoplasm, primitive neuroectodermal (pnet)
  • Oligodendroglioma of brain
  • Primary malignant neoplasm of brain
  • Primitive neuroectodermal tumor
  • Secondary malignant neoplasm of spinal cord from neoplasm of brain
Clinical Information
  • A primary or metastatic malignant neoplasm affecting the brain.
  • Cancer of the brain is usually called a brain tumor. There are two main types. A primary brain tumor starts in the brain. A metastatic brain tumor starts somewhere else in the body and moves to the brain. Brain tumors can be benign, with no cancer cells, or malignant, with cancer cells that grow quickly.brain tumors can cause many symptoms. Some of the most common are
    • headaches, usually worse in the morning
    • nausea and vomiting
    • changes in your ability to talk, hear, or see
    • problems with balance or walking
    • problems with thinking or memory
    • muscle jerking or twitching
    • numbness or tingling in arms or legs
    doctors diagnose brain tumors by doing a neurologic exam and tests including an mri, ct scan, and biopsy. People with brain tumors have several treatment options. The options are surgery, radiation therapy, and chemotherapy. Many people get a combination of treatments. nih: national cancer institute
ICD-10-CM C71.9 is grouped within Diagnostic Related Group(s) (MS-DRG v38.0):
  • 054 Nervous system neoplasms with mcc
  • 055 Nervous system neoplasms without mcc

Convert C71.9 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
  • 2021 (effective 10/1/2020): No change

Diagnosis Index entries containing back-references to C71.9:

ICD-10-CM Codes Adjacent To C71.9
C71 Malignant neoplasm of brain
C71.0 Malignant neoplasm of cerebrum, except lobes and ventricles
C71.1 Malignant neoplasm of frontal lobe
C71.2 Malignant neoplasm of temporal lobe
C71.3 Malignant neoplasm of parietal lobe
C71.4 Malignant neoplasm of occipital lobe
C71.5 Malignant neoplasm of cerebral ventricle
C71.6 Malignant neoplasm of cerebellum
C71.7 Malignant neoplasm of brain stem
C71.8 Malignant neoplasm of overlapping sites of brain
C71.9 Malignant neoplasm of brain, unspecified
C72 Malignant neoplasm of spinal cord, cranial nerves and other parts of central nervous system
C72.0 Malignant neoplasm of spinal cord
C72.1 Malignant neoplasm of cauda equina
C72.2 Malignant neoplasm of olfactory nerve
C72.20 Malignant neoplasm of unspecified olfactory nerve
C72.21 Malignant neoplasm of right olfactory nerve
C72.22 Malignant neoplasm of left olfactory nerve
C72.3 Malignant neoplasm of optic nerve
C72.30 Malignant neoplasm of unspecified optic nerve
C72.31 Malignant neoplasm of right optic nerve

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.