C39 Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs

The ICD-10-CM code for Malignant neoplasm of other and ill-defined sites in the respiratory system and intrathoracic organs is C39 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Chapter

2: Neoplasms (C00-D49)

Section

C30-C39: Malignant neoplasms of respiratory and intrathoracic organs (C30-C39)

Category C39

3 codes (2 billable)

FY2026 Status

Stable since FY2024

Official Coding Guidelines

Tx of primary site (TOC entry)

a. Admission/Encounter for treatment of primary site ............................................................. 33

Tx of secondary site (TOC entry)

b. Admission/Encounter for treatment of secondary site .......................................................... 33

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool