2027 ICD-10-CM Diagnosis Code C79.32Secondary malignant neoplasm of cerebral meninges

ICD-10-CM Codes›C00–D49›C76-C80›C79

ICD-10-CM C79.32
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

C79.32 is a billable ICD-10-CM diagnosis code for secondary malignant neoplasm of cerebral meninges. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 54 through 55. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 22 closely related codes. Coders also document this condition as malignant neoplasm of brain meninges. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Secondary malignancies.

For Medicare Advantage risk adjustment, C79.32 maps to CMS-HCC Category 17 (Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic) under the V28 model, adding a risk factor of about 4.209 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
C79.32
Billable Status
Yes — Valid for Submission
Code Describes
Secondary malignant neoplasm of cerebral meninges
Short Description
Secondary malignant neoplasm of cerebral meninges
Same as the full description in the CMS dataset.
Parent Code
C79.3
Secondary malignant neoplasm of brain and cerebral meninges

Code Classification

ChapterC00–D49Neoplasms
SectionC76-C80Malignant neoplasms of ill-defined, other secondary and unspecified sites
CategoryC79Secondary malignant neoplasm of other and unspecified sites
This CodeC79.32Secondary malignant neoplasm of cerebral meninges

Medicare Risk Adjustment (HCC)Billing

C79.32 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 17— Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic
Payment HCC · PY 2027 one of 78 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+4.209
community, non-dual, aged · ranges 1.952–4.235 across segments
Hierarchy
Supersedes HCC 18, HCC 19, HCC 20, HCC 21, HCC 22, and HCC 23
less severe related categories are not paid alongside HCC 17
Prior Model (CMS-HCC V24)
HCC 8
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 8 · ESRD (V21): HCC 8 · ESRD (V24): HCC 8
ESRD V21 weights: 0.295 dialysis, 1.289–2.627 functioning graft · ESRD V24 weights: 0.353 dialysis, 1.571–3.226 functioning graft
Part D (RxHCC)
RxHCC 18 — Secondary Cancer of Lung, Liver, Brain, and Other Sites
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Malignant neoplasm of brain meninges
  • Metastatic malignant neoplasm of meninges
  • Metastatic malignant neoplasm to brain meninges

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to C79.32: its own notes plus those printed at C79 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.

From C79 Secondary malignant neoplasm of other and unspecified sites applies to 25 codes
  • secondary carcinoid tumors (C7B.-)
  • secondary neuroendocrine tumors (C7B.-)

Notes

General instructions on how these codes are used.

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 C79.32, its category, or a range that includes it.

Applicable To 2

These notes mention C79.32.

  • Z85.8 Personal history of malignant neoplasms of other organs and systems
    Conditions classifiable to C00-C14, C40-C49, C69-C75, C7A.098, C76-C79 names C76-C79, which includes this code
  • Z85.89 Personal history of malignant neoplasm of other organs and systems
    Conditions classifiable to C7A.098, C76, C77-C79 names C77-C79, which includes this code

Clinical ClassificationClinical

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

CCSR NEO070
Secondary malignancies
Default principal diagnosis: inpatient Yes · outpatient Yes

Table of NeoplasmsClinical

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

SiteMalig.
Primary		Malig.
Secondary		Ca
in situ		BenignUncertainUnspec.
arachnoid › cerebralC70.0C79.32–D32.0D42.0D49.7
brain NEC › meningesC70.0C79.32–D32.0D42.0D49.7
cerebrum, cerebral (cortex) (hemisphere) (white matter) › meningesC70.0C79.32–D32.0D42.0D49.7
cranial (fossa, any) › meningesC70.0C79.32–D32.0D42.0D49.7
dura (cranial) (mater) › cerebralC70.0C79.32–D32.0D42.0D49.7
falx (cerebella) (cerebri)C70.0C79.32–D32.0D42.0D49.7
meninges › brainC70.0C79.32–D32.0D42.0D49.7
meninges › cerebralC70.0C79.32–D32.0D42.0D49.7
meninges › cranialC70.0C79.32–D32.0D42.0D49.7
meninges › intracranialC70.0C79.32–D32.0D42.0D49.7
pia mater › cerebralC70.0C79.32–D32.0D42.0D49.7
pia mater › cranialC70.0C79.32–D32.0D42.0D49.7
subduralC70.9C79.32–D32.9D42.9D49.7
tentorium (cerebelli)C70.0C79.32–D32.0D42.0D49.7

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 C79.32 to ICD-9-CMHistory

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

ICD-9-CM
198.4 Sec malig neo nerve NEC
Approximate The match is approximate rather than exact.

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 C79.32Overview

What is the ICD-10 code for secondary malignant neoplasm of cerebral meninges?

The ICD-10-CM code for secondary malignant neoplasm of cerebral meninges is C79.32 (sometimes written as C7932). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is C79.32 (Secondary malignant neoplasm of brain and cerebral meninges) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report secondary malignant neoplasm of cerebral meninges on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does C79.32 group to?

When secondary malignant neoplasm of cerebral meninges is the principal diagnosis on an inpatient stay, it groups to MS-DRG 55, 54, with relative weights from 1.0291 to 1.5197 depending on complications. Higher weights mean higher Medicare reimbursement.

Is C79.32 a CC or MCC?

CMS lists C79.32 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 22 closely related codes in its exclusion list.

Can C79.32 be reported with a code from C7B?

Not as a rule. The Excludes1 note at C79, which applies to C79.32, lists "secondary carcinoid tumors (C7B.-)". 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).

What HCC is C79.32?

C79.32 (secondary malignant neoplasm of cerebral meninges) maps to CMS-HCC Category 17 (Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic), commonly written as HCC 17, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 8 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 18.

Does C79.32 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, C79.32 adds a risk adjustment factor of about 4.209 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 1.952 to 4.235 depending on the payment segment). HCC 17 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 17 category page.