C34.91 — Malignant neoplasm of unspecified part of right bronchus or lung
Is C34.91 billable?
Yes, but C34.91 is an unspecified code. C34.91 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, C34.91 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting C34.91 — the more specific alternatives are listed below.
C34.91 at a glance
| Code | C34.91 |
|---|---|
| Description | Malignant neoplasm of unspecified part of right bronchus or lung |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does C34.91 group to?
C34.91 sits in MDC 04 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 180Respiratory Neoplasms with MCCmedical
- 181Respiratory Neoplasms with CCmedical
- 182Respiratory Neoplasms without CC/MCCmedical
As a secondary diagnosis, C34.91 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
Excludes1 — never code together — inherited from C30-C39
The conditions below can never be reported together with C34.91 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- mesothelioma (C45.-)
Excludes1 — never code together — inherited from C34
The conditions below can never be reported together with C34.91 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Use additional code — inherited from C34
Report an additional code alongside C34.91 to fully describe the condition. C34.91 is sequenced first.
How long has C34.91 existed?
C34.91 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.