2027 ICD-10-CM Diagnosis Code D43Neoplasm of uncertain behavior of brain and central nervous system

ICD-10-CM Codes›C00–D49›D37-D48›D43

ICD-10-CM D43
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

D43 is a non-billable ICD-10-CM category code for neoplasm of uncertain behavior of brain and central nervous system, so it cannot be submitted on claims. Use a more specific code from this category instead, such as D43.0, D43.1, D43.2, and D43.3.

Code Identity

ICD-10-CM Code
D43
Billable Status
No — Non-Billable Category
Code Describes
Neoplasm of uncertain behavior of brain and central nervous system
Short Description
Neoplasm of uncertain behavior of brain and cnsl
Chapter
D37-D48
Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes

Code Classification

ChapterC00–D49Neoplasms
SectionD37-D48Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
CategoryD43Neoplasm of uncertain behavior of brain and central nervous system
This CodeD43Neoplasm of uncertain behavior of brain and central nervous system

Specific Coding for Neoplasm of uncertain behavior of brain and cnslOverview

Non-specific codes like D43 require more characters. Use one of these billable codes instead:

  • Use D43.0 for Neoplasm of uncertain behavior of brain, supratentorial

  • Use D43.1 for Neoplasm of uncertain behavior of brain, infratentorial

  • Use D43.2 for Neoplasm of uncertain behavior of brain, unspecified

  • Use D43.3 for Neoplasm of uncertain behavior of cranial nerves

  • Use D43.4 for Neoplasm of uncertain behavior of spinal cord

  • Use D43.8 for Neoplasm of uncertain behavior of other specified parts of central nervous system

  • Use D43.9 for Neoplasm of uncertain behavior of central nervous system, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to D43: its own notes plus those printed at block D37-D48 and Chapter 2. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

On D43 itself
  • neoplasm of uncertain behavior of peripheral nerves and autonomic nervous system (D48.2)
From Block D37-D48 Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes applies to 137 codes
  • neoplasms of unspecified behavior (D49.-)

Notes

General instructions on how these codes are used.

From Block D37-D48 Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes applies to 137 codes
  • Categories D37-D44, and D48 classify by site neoplasms of uncertain behavior, i.e., histologic confirmation whether the neoplasm is malignant or benign cannot be made.
From Chapter 2 (C00-D49) Neoplasms applies to 1,730 codes
  • 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).

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name D43, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming D43: its condition is not part of those codes, and both may be reported when the patient has both.

  • D49 Neoplasms of unspecified behavior
    neoplasms of uncertain behavior (D37-D44, D48) names D37-D44, which includes this code

Notes 1

These notes mention D43.

  • Block D37-D48 Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
    Categories D37-D44, and D48 classify by site neoplasms of uncertain behavior, i.e., histologic confirmation whether the neoplasm is malignant or benign cannot be made. names D37-D44, which includes this code

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.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About D43Overview

What is the ICD-10 code for neoplasm of uncertain behavior of brain and central nervous system?

D43 is the ICD-10-CM category for neoplasm of uncertain behavior of brain and central nervous system, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is D43 a billable code?

No. This is a category header that groups the codes for neoplasm of uncertain behavior of brain and central nervous system, and headers cannot be submitted on claims. Claims for neoplasm of uncertain behavior of brain and central nervous system need a more specific code from this category, such as D43.0, D43.1, and D43.2.

Can D43 be reported with D48.2?

Not as a rule. The Excludes1 note on D43 lists "neoplasm of uncertain behavior of peripheral nerves and autonomic nervous system (D48.2)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).