2026 ICD-10-CM Diagnosis Code C78.30Secondary malignant neoplasm of unspecified respiratory organ

ICD-10-CM Codes›C00–D49›C76-C80›C78

ICD-10-CM C78.30
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C78.30 is a billable ICD-10-CM diagnosis code for secondary malignant neoplasm of unspecified respiratory organ. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 180 through 182. Coders also document this condition as metastatic malignant neoplasm to respiratory and digestive systems. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Secondary malignancies.

Code Identity

ICD-10-CM Code
C78.30
Billable Status
Yes — Valid for Submission
Code Describes
Secondary malignant neoplasm of unspecified respiratory organ
Short Description
Secondary malignant neoplasm of unsp respiratory organ
Parent Code
C78.3
Secondary malignant neoplasm of other and unspecified respiratory organs

Code Classification

ChapterC00–D49Neoplasms
SectionC76-C80Malignant neoplasms of ill-defined, other secondary and unspecified sites
CategoryC78Secondary malignant neoplasm of respiratory and digestive organs
This CodeC78.30Secondary malignant neoplasm of unspecified respiratory organ

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Metastatic malignant neoplasm to respiratory and digestive systems
  • Metastatic malignant neoplasm to respiratory tract
  • Metastatic malignant neoplasm to upper respiratory tract

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.
respiratoryC39.9C78.30D02.4D14.4D38.6D49.1
respiratory › organs or system NECC39.9C78.30D02.4D14.4D38.6D49.1
respiratory › tract NECC39.9C78.30D02.4D14.4D38.5D49.1
respiratory › tract NEC › upperC39.0C78.30D02.4D14.4D38.5D49.1

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Convert C78.30 to ICD-9-CMHistory

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

ICD-9-CM
197.3 Sec malig neo resp 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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About C78.30Overview

Is C78.30 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report secondary malignant neoplasm of unspecified respiratory organ on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C78.30 group to?

When secondary malignant neoplasm of unspecified respiratory organ is the principal diagnosis on an inpatient stay, it groups to MS-DRG 180, 181, 182, with relative weights from 0.7440 to 1.7660 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C78.30?

Under the General Equivalence Mappings, secondary malignant neoplasm of unspecified respiratory organ converts to ICD-9-CM 197.3 (sec malig neo resp NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.