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ICD-10-CM 2027 diagnosis code

D49.6Neoplasm of unspecified behavior of brain

✓ Billable / specific

D49.6 is a valid, billable ICD-10-CM code for neoplasm of unspecified behavior of brain. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About D49.6

D49.6 is the ICD-10-CM diagnosis code for neoplasm of unspecified behavior of brain. It belongs to category D49 (neoplasms of unspecified behavior), block D49 (neoplasms of unspecified behavior) and chapter 2 (neoplasms). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within D49 (neoplasms of unspecified behavior), D49.6 is specifically for neoplasm of unspecified behavior of brain. Related codes cover digestive system (D49.0), respiratory system (D49.1), bone, soft tissue, and skin (D49.2), breast (D49.3), bladder (D49.4), other genitourinary organs (D49.5), endocrine glands and other parts of nervous system (D49.7), other specified sites (D49.8) and 1 more.

Don't report D49.6 together with the conditions in its Excludes1 note: neoplasm of unspecified behavior of cerebral meninges (D49.7) and neoplasm of unspecified behavior of cranial nerves (D49.7).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 054 (Nervous System Neoplasms with MCC, relative weight 1.5194) and DRG 055 (Nervous System Neoplasms without MCC, relative weight 1.0296), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 239.6 (neoplasm of unspecified nature of brain).

Coding notes

Excludes1Not coded here — never report together with this code
  • neoplasm of unspecified behavior of cerebral meninges (D49.7)
  • neoplasm of unspecified behavior of cranial nerves (D49.7)

Notes that apply from higher levels

Instructions written at a parent level also apply to D49.6.

› From D49 Neoplasms of unspecified behavior
Note
  • Category D49 classifies by site neoplasms of unspecified morphology and behavior. The term 'mass', unless otherwise stated, is not to be regarded as a neoplastic growth.
Includes
  • 'growth' NOS
  • neoplasm NOS
  • new growth NOS
  • tumor NOS
Excludes2
  • neoplasms of uncertain behavior (D37-D44, D48)

Broader instructions also apply from Chapter 2: Neoplasms.

Alphabetic index entries

1 entries

Terms in the official ICD-10-CM index that lead to D49.6.

Table of Drugs & Neoplasms entries

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 239.6Neoplasm of unspecified nature of brainexact

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about D49.6

Is D49.6 billable?

Yes. D49.6 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can D49.6 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict D49.6 as a principal diagnosis.

Is D49.6 a CC or MCC?

No. D49.6 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does D49.6 group to?

D49.6 is used in the MS-DRG v44.0 logic for MS-DRG 054 (Nervous System Neoplasms with MCC) and MS-DRG 055 (Nervous System Neoplasms without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for D49.6?

The CMS General Equivalence Mappings map D49.6 to ICD-9-CM 239.6.