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D49.6 ICD-10-CM Code: Neoplasm of unspecified behavior of brain

Compare with another code for D49.6Check this code on a claim

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
4 inclusion terms · 2 Excludes1 · 1 Excludes2
Risk adjustment
CMS-HCC V28: 1 category · CMS-HCC V22 category 12 · RxHCC V08 category 22

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too, and is marked with where it comes from.

Excludes1Not reported with this code unless documented as unrelated
  • neoplasm of unspecified behavior of cerebral meninges (D49.7)
  • neoplasm of unspecified behavior of cranial nerves (D49.7)
Excludes2from D49Not included here; may be reported together
  • neoplasms of uncertain behavior (D37-D44, D48)
Includesfrom D49What D49 covers
  • 'growth' NOS
  • neoplasm NOS
  • new growth NOS
  • tumor NOS

Where it sits Source: CMS/NCHS

Under:Chapter 2: NeoplasmsD49 Neoplasms of unspecified behavior

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v44, Appendix B.

  • MS-DRG 054 — NERVOUS SYSTEM NEOPLASMS WITH MCC (MDC 01)
  • MS-DRG 055 — NERVOUS SYSTEM NEOPLASMS WITHOUT MCC (MDC 01)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Risk Adjustment (CMS-HCC)

Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.

  • HCC 23 — Prostate, Breast, and Other Cancers and Tumors

Other models: CMS-HCC V22 HCC 12 · RxHCC V08 HCC 22

Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for D49.6 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on D49.6 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • 'growth' NOS
  • neoplasm NOS
  • new growth NOS
  • tumor NOS

Source: inherited from D49

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

Source: inherited from D49

Coder workflow for D49.6

MedCoder structured workflow — derived from this code’s own official record

Before you code D49.6

  1. Unspecified does not mean incorrect. When the record gives no greater specificity, D49.6 may be the appropriate code. No code beside it in this subcategory is more specific; when the record documents what the title leaves unspecified, look the documented term up in the Alphabetic Index, which may lead to a code outside this subcategory. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18, I.B.1).

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

  2. Confirm the documented site and behavior (this code’s block classifies unspecified behavior neoplasms), whether the site is primary or secondary, and whether the malignancy is current or a personal history: a previously excised malignancy with no further treatment and no evidence of disease is history, not current disease. Verify the site against the Table of Neoplasms. Neoplasm chapter guidelines (Guidelines I.C.2.a, I.C.2.d, I.C.2.m).

    See the Table of Neoplasms entries · Guide: Active cancer vs history of cancer →

  3. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with D49.6. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the record document the detail this title leaves unspecified?
    Yes → Look the documented term up in the Alphabetic Index; the code it leads to may sit outside this subcategory.
    No → Continue — D49.6 is appropriate when the documentation goes no further.
  2. Does the documentation support a condition named in D49.6’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewD49.7

Consider D49.6. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Anatomical site
At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.
Behavior and current-versus-history status
Malignant, in situ, benign or uncertain; primary or secondary; current disease or personal history (Guidelines I.C.2.m).
Any detail beyond this code’s title
What the record states that a more specific code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting D49.6(2 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with D49.6: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareD49.7

    See the official tabular notes · Guidelines I.A.12.a

  • Excludes2 — not part of D49.6(1 note)

    Coding workflow: The conditions named in this note are not included in D49.6. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareD48

    See the official tabular notes · Guidelines I.A.12.b

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.

Coding question: Is a more specific code supportable?

Path: No sibling in this subcategory is more specific; look the documented detail up in the Alphabetic Index.

Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).

Documentation: Both the condition D49.6 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewD49.7

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse D49.6 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of D49.6 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • D49.7— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of neoplasm of unspecified behavior of cerebral meninges moves the case to D49.7; the two are not reported together unless documented as unrelated.

    Full comparison: D49.6 vs D49.7 →

  • D37— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of neoplasms of uncertain behavior adds D37; it is not part of this code and both may be reported when both are documented.

    Full comparison: D49.6 vs D37 →

  • D44— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of neoplasms of uncertain behavior adds D44; it is not part of this code and both may be reported when both are documented.

    Full comparison: D49.6 vs D44 →

  • D48— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of neoplasms of uncertain behavior adds D48; it is not part of this code and both may be reported when both are documented.

    Full comparison: D49.6 vs D48 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Neoplasm of unspecified behavior of brain is a billable ICD-10-CM diagnosis code (D49.6).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

  • No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name D49.6 or its code family, from the CMS ICD-10-CM tabular instructional notes and the CMS Table of Neoplasms. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 13 Excludes1 notes: D37 — Neoplasm of uncertain behavior of oral cavity and digestive organs (via D49.-), D37-D48 — Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes (D37-D48) (via D49.-), D38 — Neoplasm of uncertain behavior of middle ear and respiratory and intrathoracic organs (via D49.-), D39 — Neoplasm of uncertain behavior of female genital organs (via D49.-), D40 — Neoplasm of uncertain behavior of male genital organs (via D49.-), D41 — Neoplasm of uncertain behavior of urinary organs (via D49.-), D42 — Neoplasm of uncertain behavior of meninges (via D49.-), D43 — Neoplasm of uncertain behavior of brain and central nervous system (via D49.-), D44 — Neoplasm of uncertain behavior of endocrine glands (via D49.-), D45 — Polycythemia vera (via D49.-), D46 — Myelodysplastic syndromes (via D49.-), D47 — Other neoplasms of uncertain behavior of lymphoid, hematopoietic and related tissue (via D49.-), D48 — Neoplasm of uncertain behavior of other and unspecified sites (via D49.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 17 Same-site neoplasm codes: C71.0 — Malignant neoplasm of cerebrum, except lobes and ventriclesCompare D49.6 vs C71.0 →, C71.1 — Malignant neoplasm of frontal lobeCompare D49.6 vs C71.1 →, C71.2 — Malignant neoplasm of temporal lobeCompare D49.6 vs C71.2 →, C71.3 — Malignant neoplasm of parietal lobeCompare D49.6 vs C71.3 →, C71.4 — Malignant neoplasm of occipital lobeCompare D49.6 vs C71.4 →, C71.5 — Malignant neoplasm of cerebral ventricleCompare D49.6 vs C71.5 →, C71.6 — Malignant neoplasm of cerebellumCompare D49.6 vs C71.6 →, C71.7 — Malignant neoplasm of brain stemCompare D49.6 vs C71.7 →, C71.8 — Malignant neoplasm of overlapping sites of brainCompare D49.6 vs C71.8 →, C71.9 — Malignant neoplasm of brain, unspecifiedCompare D49.6 vs C71.9 →, C79.31 — Secondary malignant neoplasm of brainCompare D49.6 vs C79.31 →, D33.0 — Benign neoplasm of brain, supratentorialCompare D49.6 vs D33.0 →, D33.1 — Benign neoplasm of brain, infratentorialCompare D49.6 vs D33.1 →, D33.2 — Benign neoplasm of brain, unspecifiedCompare D49.6 vs D33.2 →, D43.0 — Neoplasm of uncertain behavior of brain, supratentorialCompare D49.6 vs D43.0 →, D43.1 — Neoplasm of uncertain behavior of brain, infratentorialCompare D49.6 vs D43.1 →, D43.2 — Neoplasm of uncertain behavior of brain, unspecifiedCompare D49.6 vs D43.2 →.

These codes represent related neoplasm behaviors affecting the same anatomic site.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 2 MS-DRGs: DRG 054 (MDC 01), DRG 055 (MDC 01).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):NEO072 — Neoplasms of unspecified nature or uncertain behavior (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Prostate, Breast, and Other Cancers and Tumors) for risk-adjusted payment.

D43.4 — Neoplasm of uncertain behavior of spinal cord, D43.8 — Neoplasm of uncertain behavior of other specified parts of central nervous system, D43.9 — Neoplasm of uncertain behavior of central nervous system, unspecified, D44.3 — Neoplasm of uncertain behavior of pituitary gland, D44.4 — Neoplasm of uncertain behavior of craniopharyngeal duct, D44.5 — Neoplasm of uncertain behavior of pineal gland, D44.6 — Neoplasm of uncertain behavior of carotid body, D44.7 — Neoplasm of uncertain behavior of aortic body and other paraganglia, D45 — Polycythemia vera, D47.3 — Essential (hemorrhagic) thrombocythemia, Q85.00 — Neurofibromatosis, unspecified, Q85.01 — Neurofibromatosis, type 1, Q85.02 — Neurofibromatosis, type 2, Q85.03 — Schwannomatosis, Q85.09 — Other neurofibromatosis, Q85.1 — Tuberous sclerosis, Q85.81 — PTEN hamartoma tumor syndrome, Q85.82 — Other Cowden syndrome, Q85.83 — Von Hippel-Lindau syndrome, Q85.89 — Other phakomatoses, not elsewhere classified, +213 more

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic, Cancer Metastatic to Bone, Other and Unspecified Metastatic Cancer; Acute Leukemia Except Myeloid, Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers, Lung and Other Severe Cancers, Lymphoma and Other Cancers, Bladder, Colorectal, and Other Cancers

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Neoplasms of unspecified nature or uncertain behavior).

D48.5 — Neoplasm of uncertain behavior of skin, D48.60 — Neoplasm of uncertain behavior of unspecified breast, D48.61 — Neoplasm of uncertain behavior of right breast, D48.62 — Neoplasm of uncertain behavior of left breast, D48.7 — Neoplasm of uncertain behavior of other specified sites, D48.9 — Neoplasm of uncertain behavior, unspecified, D49.0 — Neoplasm of unspecified behavior of digestive system, D49.1 — Neoplasm of unspecified behavior of respiratory system, D49.2 — Neoplasm of unspecified behavior of bone, soft tissue, and skin, D49.3 — Neoplasm of unspecified behavior of breast, D49.4 — Neoplasm of unspecified behavior of bladder, D49.5 — Neoplasm of unspecified behavior of other genitourinary organs, D49.511 — Neoplasm of unspecified behavior of right kidney, D49.512 — Neoplasm of unspecified behavior of left kidney, D49.519 — Neoplasm of unspecified behavior of unspecified kidney, D49.59 — Neoplasm of unspecified behavior of other genitourinary organ, D49.7 — Neoplasm of unspecified behavior of endocrine glands and other parts of nervous system, D49.81 — Neoplasm of unspecified behavior of retina and choroid, D49.89 — Neoplasm of unspecified behavior of other specified sites, D49.9 — Neoplasm of unspecified behavior of unspecified site, +100 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Degeneration, degenerative”; these codes share that main term but sit in a different category of the Tabular List.

A17.81 — Tuberculoma of brain and spinal cord (spinal, tuberculous), A18.83 — Tuberculosis of digestive tract organs, not elsewhere classified (pancreas, tuberculous), A52.06 — Other syphilitic heart involvement (myocardial, myocardium, syphilitic), D51.0 — Vitamin B12 deficiency anemia due to intrinsic factor deficiency (combined, with anemia), D51.3 — Other dietary vitamin B12 deficiency anemia (combined, with anemia, due to dietary vitamin B12 deficiency), D51.9 — Vitamin B12 deficiency anemia, unspecified (combined, in, vitamin B12 deficiency, anemia), D73.0 — Hyposplenism (spleen), E03.9 — Hypothyroidism, unspecified (brain, in, myxedema), E07.89 — Other specified disorders of thyroid (thyroid), E23.6 — Other disorders of pituitary gland (pituitary), E27.8 — Other specified disorders of adrenal gland (adrenal), E32.8 — Other diseases of thymus (thymus), E34.8 — Other specified endocrine disorders (pineal gland), E51.2 — Wernicke's encephalopathy (brain, in, beriberi), E53.8 — Deficiency of other specified B group vitamins (combined), E75.21 — Fabry (-Anderson) disease (brain, in, Fabry-Anderson disease), E75.22 — Gaucher disease (brain, in, Gaucher's disease), E75.249 — Niemann-Pick disease, unspecified (brain, in, Niemann-Pick disease), E75.3 — Sphingolipidosis, unspecified (brain, in, sphingolipidosis), E75.4 — Neuronal ceroid lipofuscinosis (brain, in, lipidosis, cerebral), +119 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Iron Panel

Contextual Map

Every relationship of D49.6 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run D49.6 with these 9 related codes in Claim Check

Hierarchy

Excludes1

Same site (17)

Index manifestation

Referenced by Excludes1 notes (13)

Referenced by Same-site neoplasm codes (17)

Clinical classification (CCSR)

Risk adjustment (CMS-HCC)

  • HCC 23 — Prostate, Breast, and Other Cancers and Tumors [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

MDC crossing

  • MDC 01 — Diseases and Disorders of the Nervous System[MDC crossing]: “Diseases and Disorders of the Nervous System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 8,919 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Neoplasm sites (87)

  • Neoplasm, neoplastic, basal ganglia — Neoplasm, neoplastic, basal ganglia — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, basal ganglia (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, basis pedunculi — Neoplasm, neoplastic, basis pedunculi — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, basis pedunculi (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, brain NEC — Neoplasm, neoplastic, brain NEC — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, brain NEC (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, brain NEC, basal ganglia — Neoplasm, neoplastic, brain NEC, basal ganglia — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, brain NEC, basal ganglia (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, brain NEC, cerebellopontine angle — Neoplasm, neoplastic, brain NEC, cerebellopontine angle — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, brain NEC, cerebellopontine angle (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, brain NEC, cerebellum NOS — Neoplasm, neoplastic, brain NEC, cerebellum NOS — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, brain NEC, cerebellum NOS (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, brain NEC, cerebrum — Neoplasm, neoplastic, brain NEC, cerebrum — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, brain NEC, cerebrum (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, brain NEC, choroid plexus — Neoplasm, neoplastic, brain NEC, choroid plexus — Unspecified Behavior [Neoplasm table]: “Neoplasm, neoplastic, brain NEC, choroid plexus (Unspecified Behavior)”— CMS Table of Neoplasms · icd10cm-fy2027
  • and 79 more

Index entries

  • Degeneration, degenerative, brain (cortical) (progressive), in, neoplastic disease[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027

Nearest codes (17)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Indexed Clinical Terms (1)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Neoplasm Table Sites (87)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Anatomical sites from the official ICD-10-CM Table of Neoplasms that map to this code, with the matching behavior column.

  • Neoplasm, neoplastic, basal ganglia — Unspecified Behavior
  • Neoplasm, neoplastic, basis pedunculi — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, basal ganglia — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, cerebellopontine angle — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, cerebellum NOS — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, cerebrum — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, choroid plexus — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, corpus callosum — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, corpus striatum — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, cortex (cerebral) — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, frontal lobe — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, globus pallidus — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, hippocampus — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, hypothalamus — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, internal capsule — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, medulla oblongata — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, midbrain — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, occipital lobe — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, parietal lobe — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, peduncle — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, pons — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, stem — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, tapetum — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, temporal lobe — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, thalamus — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, uncus — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, ventricle (floor) — Unspecified Behavior
  • Neoplasm, neoplastic, brain NEC, ventricle (floor), fourth — Unspecified Behavior
  • Neoplasm, neoplastic, cerebellopontine (angle) — Unspecified Behavior
  • Neoplasm, neoplastic, cerebellum, cerebellar — Unspecified Behavior
  • Neoplasm, neoplastic, cerebrum, cerebral (cortex) (hemisphere) (white matter) — Unspecified Behavior
  • Neoplasm, neoplastic, cerebrum, cerebral (cortex) (hemisphere) (white matter), peduncle — Unspecified Behavior
  • Neoplasm, neoplastic, cerebrum, cerebral (cortex) (hemisphere) (white matter), ventricle — Unspecified Behavior
  • Neoplasm, neoplastic, cerebrum, cerebral (cortex) (hemisphere) (white matter), ventricle, fourth — Unspecified Behavior
  • Neoplasm, neoplastic, choroid, plexus — Unspecified Behavior
  • Neoplasm, neoplastic, corpus, callosum, brain — Unspecified Behavior
  • Neoplasm, neoplastic, corpus, striatum, cerebrum — Unspecified Behavior
  • Neoplasm, neoplastic, cortex, cerebral — Unspecified Behavior
  • Neoplasm, neoplastic, cranial (fossa, any) — Unspecified Behavior
  • Neoplasm, neoplastic, ependyma (brain) — Unspecified Behavior
  • Neoplasm, neoplastic, ependyma (brain), fourth ventricle — Unspecified Behavior
  • Neoplasm, neoplastic, fossa (of), anterior (cranial) — Unspecified Behavior
  • Neoplasm, neoplastic, fossa (of), cranial — Unspecified Behavior
  • Neoplasm, neoplastic, fossa (of), middle (cranial) — Unspecified Behavior
  • Neoplasm, neoplastic, fossa (of), posterior (cranial) — Unspecified Behavior
  • Neoplasm, neoplastic, frontal, lobe, brain — Unspecified Behavior
  • Neoplasm, neoplastic, frontal, pole — Unspecified Behavior
  • Neoplasm, neoplastic, ganglia, basal — Unspecified Behavior
  • Neoplasm, neoplastic, globus pallidus — Unspecified Behavior
  • Neoplasm, neoplastic, hemisphere, cerebral — Unspecified Behavior
  • Neoplasm, neoplastic, hippocampus, brain — Unspecified Behavior
  • Neoplasm, neoplastic, hypothalamus — Unspecified Behavior
  • Neoplasm, neoplastic, insula — Unspecified Behavior
  • Neoplasm, neoplastic, insular tissue (pancreas), brain — Unspecified Behavior
  • Neoplasm, neoplastic, internal, capsule — Unspecified Behavior
  • Neoplasm, neoplastic, intracranial NEC — Unspecified Behavior
  • Neoplasm, neoplastic, island of Reil — Unspecified Behavior
  • Neoplasm, neoplastic, medulla, oblongata — Unspecified Behavior
  • Neoplasm, neoplastic, midbrain — Unspecified Behavior
  • Neoplasm, neoplastic, motor tract, brain — Unspecified Behavior
  • Neoplasm, neoplastic, occipital, lobe or pole, brain — Unspecified Behavior
  • Neoplasm, neoplastic, olive (brain) — Unspecified Behavior
  • Neoplasm, neoplastic, operculum (brain) — Unspecified Behavior
  • Neoplasm, neoplastic, pallium — Unspecified Behavior
  • Neoplasm, neoplastic, parietal, lobe, brain — Unspecified Behavior
  • Neoplasm, neoplastic, peduncle, cerebral — Unspecified Behavior
  • Neoplasm, neoplastic, plexus, choroid — Unspecified Behavior
  • Neoplasm, neoplastic, pole, frontal — Unspecified Behavior
  • Neoplasm, neoplastic, pole, occipital — Unspecified Behavior
  • Neoplasm, neoplastic, pons (varolii) — Unspecified Behavior
  • Neoplasm, neoplastic, posterior fossa (cranial) — Unspecified Behavior
  • Neoplasm, neoplastic, putamen — Unspecified Behavior
  • Neoplasm, neoplastic, pyramid (brain) — Unspecified Behavior
  • Neoplasm, neoplastic, rhinencephalon — Unspecified Behavior
  • Neoplasm, neoplastic, spine, spinal (column), bulb — Unspecified Behavior
  • Neoplasm, neoplastic, stem, brain — Unspecified Behavior
  • Neoplasm, neoplastic, suprasellar (region) — Unspecified Behavior
  • Neoplasm, neoplastic, supratentorial NEC (brain) — Unspecified Behavior
  • Neoplasm, neoplastic, tapetum, brain — Unspecified Behavior
  • Neoplasm, neoplastic, temporal, lobe or pole — Unspecified Behavior
  • Neoplasm, neoplastic, thalamus — Unspecified Behavior
  • Neoplasm, neoplastic, uncus, brain — Unspecified Behavior
  • Neoplasm, neoplastic, ventricle (cerebral) (floor) (lateral) (third) — Unspecified Behavior
  • Neoplasm, neoplastic, ventricle (cerebral) (floor) (lateral) (third), fourth — Unspecified Behavior
  • Neoplasm, neoplastic, vermis, cerebellum — Unspecified Behavior
  • Neoplasm, neoplastic, white matter (central) (cerebral) — Unspecified Behavior

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44 Release, file and checksum · Publisher’s page
Risk adjustment Official source data
2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "D49.6 — Neoplasm of unspecified behavior of brain." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/d49.6-neoplasm-of-unspecified-behavior-of-brain

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Neoplasm of unspecified behavior of brain

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to D49.6 in its code family, with their registry titles.

View all codes in the D49 family