C34.00
BillableMalignant neoplasm of unspecified main bronchus
HCC Category Mapping
V28HCC 20 — Lung and Other Severe Cancers
0.000V24HCC 9 — Lung and Other Severe Cancers
0.973ESRDHCC 9 — Lung and Other Severe Cancers
0.000RxHCCHCC 20 — Cancer, Liver and Intrahepatic Bile Duct
0.000What This Code Means
Cancer of the main bronchus (the large airway that branches from the trachea into the lungs) when it is unclear which side or specific location is affected.
Coding Tips
Clinical Significance
This code represents cancer of the main bronchus (carina region) without laterality specified. Main bronchial cancers are centrally located and often present with airway obstruction, hemoptysis, and post-obstructive pneumonia. These carry high RAF weight as severe cancers requiring aggressive multimodal treatment.
Documentation Requirements
- ✓Pathology confirmation with cell type (small cell, non-small cell, squamous, adenocarcinoma)
- ✓Bronchoscopy or imaging confirming main bronchus location
- ✓Evidence that laterality cannot be determined from available records
- ✓TNM staging including nodal and metastatic status
- ✓Treatment plan (surgical candidacy, chemotherapy, radiation)
Commonly Confused Codes
C34.01/C34.02 — Right/left main bronchus: Always assign laterality when documented; C34.00 is a fallbackC33 — Tracheal cancer: The boundary is at the carina; tumors above are trachealC34.10-C34.92 — Lobar lung cancers: Main bronchus is distinct from lobar or peripheral lung tumorsC78.00 — Secondary malignant neoplasm of lung: Ensure this is primary, not metastatic
Code Hierarchy
└C34Malignant neoplasm of bronchus and lung└C34.0Malignant neoplasm of main bronchus└C34.00Malignant neoplasm of unspecified main bronchus
└C34.00Malignant neoplasm of unspecified main bronchus