2026 ICD-10-CM Diagnosis Code C39Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs

ICD-10-CM Codes›C00–D49›C30-C39›C39

ICD-10-CM C39
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C39 is a non-billable ICD-10-CM category code for malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs, so it cannot be submitted on claims. Use a more specific code from this category instead, such as C39.0 and C39.9.

Code Identity

ICD-10-CM Code
C39
Billable Status
No — Non-Billable Category
Code Describes
Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs
Short Description
Malig neoplm of sites in the resp sys and intrathorac organs
Chapter
C30-C39
Malignant neoplasms of respiratory and intrathoracic organs

Code Classification

ChapterC00–D49Neoplasms
SectionC30-C39Malignant neoplasms of respiratory and intrathoracic organs
CategoryC39Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs
This CodeC39Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs

Specific Coding for Malig neoplm of sites in the resp sys and intrathorac organsOverview

Non-specific codes like C39 require more characters. Use one of these billable codes instead:

  • Use C39.0 for Malignant neoplasm of upper respiratory tract, part unspecified

  • Use C39.9 for Malignant neoplasm of lower respiratory tract, part unspecified

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Use Additional Code

  • code to identify:
  • exposure to environmental tobacco smoke Z77.22
  • exposure to tobacco smoke in the perinatal period P96.81
  • history of tobacco dependence Z87.891
  • occupational exposure to environmental tobacco smoke Z57.31
  • tobacco dependence F17
  • tobacco use Z72.0

Type 1 Excludes

  • intrathoracic malignant neoplasm NOS C76.1
  • thoracic malignant neoplasm NOS C76.1

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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 C39Overview

Is C39 a billable code?

No. This is a category header that groups the codes for malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs, and headers cannot be submitted on claims. Claims for malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs need a more specific code from this category, such as C39.0 and C39.9.