ICD-10-CM 2027
ICD-10 code for lung cancer
Malignant neoplasm of unspecified part of unspecified bronchus or lung
Confirmed by the official ICD-10-CM index entry “neoplasms|neoplasm, neoplastic › bronchiogenic, bronchogenic (lung)|malignant primary”. Page updated September 29, 2026.
About coding lung cancer
The ICD-10-CM code for lung cancer is C34.90 (Malignant neoplasm of unspecified part of unspecified bronchus or lung). The official index lists 15 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on C34.90.
Within C34.9, choose C34.90 (unspecified bronchus or lung) only when documentation doesn't support a more specific option: right bronchus or lung (C34.91) and left bronchus or lung (C34.92).
Use an additional 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.-) and 1 more.
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
Related Lung cancer codes
- C34.00 Malignant neoplasm of unspecified main bronchus
- C34.01 Malignant neoplasm of right main bronchus
- C34.02 Malignant neoplasm of left main bronchus
- C34.10 Malignant neoplasm of upper lobe, unspecified bronchus or lung
- C34.11 Malignant neoplasm of upper lobe, right bronchus or lung
- C34.12 Malignant neoplasm of upper lobe, left bronchus or lung
- C34.2 Malignant neoplasm of middle lobe, bronchus or lung
- C34.30 Malignant neoplasm of lower lobe, unspecified bronchus or lung
- C34.31 Malignant neoplasm of lower lobe, right bronchus or lung
- C34.32 Malignant neoplasm of lower lobe, left bronchus or lung
- C34.80 Malignant neoplasm of overlapping sites of unspecified bronchus and lung
- C34.81 Malignant neoplasm of overlapping sites of right bronchus and lung
- C34.82 Malignant neoplasm of overlapping sites of left bronchus and lung
- C34.91 Malignant neoplasm of unspecified part of right bronchus or lung
- C34.92 Malignant neoplasm of unspecified part of left bronchus or lung
Common questions about lung cancer ICD-10 codes
What is the ICD-10 code for lung cancer?
- C34.90 — Malignant neoplasm of unspecified part of unspecified bronchus or lung. More specific codes apply when the documentation supports them: C34.00, C34.01, C34.02, C34.10 and others below.
What is the ICD-10 code for malignant neoplasm of unspecified main bronchus?
- C34.00 — Malignant neoplasm of unspecified main bronchus.
What is the ICD-10 code for malignant neoplasm of right main bronchus?
- C34.01 — Malignant neoplasm of right main bronchus.
What is the ICD-10 code for malignant neoplasm of left main bronchus?
- C34.02 — Malignant neoplasm of left main bronchus.
What is the ICD-10 code for malignant neoplasm of upper lobe, unspecified bronchus or lung?
- C34.10 — Malignant neoplasm of upper lobe, unspecified bronchus or lung.
What is the ICD-10 code for malignant neoplasm of upper lobe, right bronchus or lung?
- C34.11 — Malignant neoplasm of upper lobe, right bronchus or lung.
What is the ICD-10 code for malignant neoplasm of upper lobe, left bronchus or lung?
- C34.12 — Malignant neoplasm of upper lobe, left bronchus or lung.
Is C34.90 billable?
- Yes. C34.90 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can C34.90 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict C34.90 as a principal diagnosis.
Is C34.90 a CC or MCC?
- C34.90 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.