ICD-10 · PDGM grouping
C34 Malignant neoplasm of bronchus and lung
All 16 codes in the C34 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
16
Can lead a claim
12
Cannot lead a claim
4
What CMS assigns to C34
12 of the 16 codes group to MMTA - Infectious Disease, Neoplasms, and Blood-Forming Diseases; 4 are assigned no clinical group. All 16 count toward the Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum comorbidity subgroup. 12 of the 16 can lead a claim.
- Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum: can award the low comorbidity tier as a secondary diagnosis.
Every code in C34
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| C34.0 Malignant neoplasm of main bronchus | ||||
| C34.00 | Malignant neoplasm of unspecified main bronchus | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.01 | Malignant neoplasm of right main bronchus | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.02 | Malignant neoplasm of left main bronchus | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.1 Malignant neoplasm of upper lobe, bronchus or lung | ||||
| C34.10 | Malignant neoplasm of upper lobe, unspecified bronchus or lungCMS: Malignant neoplasm of upper lobe, unsp bronchus or lung | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.11 | Malignant neoplasm of upper lobe, right bronchus or lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.12 | Malignant neoplasm of upper lobe, left bronchus or lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.2 | Malignant neoplasm of middle lobe, bronchus or lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.3 Malignant neoplasm of lower lobe, bronchus or lung | ||||
| C34.30 | Malignant neoplasm of lower lobe, unspecified bronchus or lungCMS: Malignant neoplasm of lower lobe, unsp bronchus or lung | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.31 | Malignant neoplasm of lower lobe, right bronchus or lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.32 | Malignant neoplasm of lower lobe, left bronchus or lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.8 Malignant neoplasm of overlapping sites of bronchus and lung | ||||
| C34.80 | Malignant neoplasm of overlapping sites of unspecified bronchus and lungCMS: Malignant neoplasm of ovrlp sites of unsp bronchus and lung | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.81 | Malignant neoplasm of overlapping sites of right bronchus and lungCMS: Malignant neoplasm of ovrlp sites of right bronchus and lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.82 | Malignant neoplasm of overlapping sites of left bronchus and lungCMS: Malignant neoplasm of ovrlp sites of left bronchus and lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.9 Malignant neoplasm of unspecified part of bronchus or lung | ||||
| C34.90 | Malignant neoplasm of unspecified part of unspecified bronchus or lungCMS: Malignant neoplasm of unsp part of unsp bronchus or lung | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.91 | Malignant neoplasm of unspecified part of right bronchus or lungCMS: Malignant neoplasm of unsp part of right bronchus or lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
| C34.92 | Malignant neoplasm of unspecified part of left bronchus or lungCMS: Malignant neoplasm of unsp part of left bronchus or lung | Can lead a claim | K | Malignant Neoplasm of Trachea, Bronchus, Lung, and Mediastinum |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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