Skip to main content

C34.9 ICD-10-CM Code: Malignant neoplasm of unspecified part of bronchus or lung

Compare with another codeCheck this code on a claim

Billing Status: NO. This is a non-billable ICD-10-CM code: report a more specific billable code beneath it.

Coding at a Glance

Tabular directives
1 inclusion term · 3 Excludes1 · 7 use-additional codes

Not billable · FY2027A non-billable heading in the tabular list: report a more specific code beneath it.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too; the Instructions section marks which is which.

Use additional codeReport with this code when documented
  • 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)

+3 more in Instructions

Excludes1Never report with this code
  • Kaposi's sarcoma of lung (C46.5-)
  • malignant carcinoid tumor of the bronchus and lung (C7A.090)
  • mesothelioma (C45.-)
IncludesWhat this code covers
  • malignant neoplasm of middle ear

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for C34.9 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on C34.9 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • malignant neoplasm of middle ear

Source: inherited from C30-C39

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use 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.-)
  • tobacco use (Z72.0)

Source: inherited from C34

Coder workflow for C34.9

MedCoder structured workflow — derived from this code’s own official record

Before you code C34.9

  1. C34.9 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

    ReviewC34.90, C34.91, C34.92

    See the relationships section · Guide: How to choose an ICD-10-CM code →

  2. Unspecified does not mean incorrect. When the record gives no greater specificity, C34.9 may be the appropriate code. Check the record for detail that supports a more specific sibling. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).

    ReviewC34.0, C34.1, C34.2, C34.3, C34.8

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

  3. Confirm the documented site and behavior (this code’s block classifies malignant neoplasms), whether the site is primary or secondary, and whether the malignancy is current or a personal history: a previously excised malignancy with no further treatment and no evidence of disease is history, not current disease. Verify the site against the Table of Neoplasms. Neoplasm chapter guidelines (Guidelines I.C.2.a, I.C.2.d, I.C.2.m).

    See the Table of Neoplasms entries · Guide: Active cancer vs history of cancer →

  4. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with C34.9. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support one of the more specific codes beneath C34.9?
    Yes → Select that code and continue the checks below on its own page.
    No → C34.9 cannot be reported as written; query for the specificity its subcategory needs.

    ReviewC34.90, C34.91, C34.92

  2. Does the record document the detail a more specific sibling code needs?
    Yes → Review the specific siblings in this subcategory.
    No → Continue — C34.9 is appropriate when the documentation goes no further.

    ReviewC34.0, C34.1, C34.2, C34.3, C34.8

  3. Does the documentation support a condition named in C34.9’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewC46.5, C7A.090, C45

Consider C34.9. Then work the Use Additional Code note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Anatomical site
At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.
The conditions the Use Additional Code note names
Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.
Behavior and current-versus-history status
Malignant, in situ, benign or uncertain; primary or secondary; current disease or personal history (Guidelines I.C.2.m).
Any detail beyond this code’s title
What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting C34.9(3 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with C34.9: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareC46.5, C7A.090, C45

    See the official tabular notes · Guidelines I.A.12.a

  • Use Additional Code — after identifying C34.9(7 notes)

    Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with C34.9 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

    ReviewZ77.22, P96.81, Z87.891, Z57.31, F17, Z72.0

    See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.

Coding question: Is a more specific sibling code supportable?

Path: Review the specific siblings in this subcategory and what each requires the record to state.

Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).

ReviewC34.0, C34.1, C34.2, C34.3, C34.8

Documentation: Both the condition C34.9 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewC46.5, C7A.090, C45

Documentation: A condition the Use Additional Code note names is documented.

Coding question: Is a second code reported with C34.9?

Path: Review the Use Additional Code note and the code it names.

Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).

ReviewZ77.22, P96.81, Z87.891, Z57.31, F17, Z72.0

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse C34.9 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of C34.9 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • C46.5— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of Kaposi's sarcoma of lung moves the case to C46.5; the two are not reported together unless documented as unrelated.

    Full comparison: C34.9 vs C46.5 →

  • C7A.090— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of malignant carcinoid tumor of the bronchus and lung moves the case to C7A.090; the two are not reported together unless documented as unrelated.

    Full comparison: C34.9 vs C7A.090 →

  • C45— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of mesothelioma moves the case to C45; the two are not reported together unless documented as unrelated.

    Full comparison: C34.9 vs C45 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Malignant neoplasm of unspecified part of bronchus or lung is a non-billable ICD-10-CM category code (C34.9). A more specific billable subcode must be selected for claims submission.

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name C34.9 or its code family, from the CMS ICD-10-CM tabular instructional notes, the CMS Table of Neoplasms and the CMS Table of Neoplasms (site match derived from the code title). Tabular-note edges are stored at the code family level that carries each note.

Referenced by 12 Excludes2 notes: J60 — Coalworker's pneumoconiosis (via C34.-), J60-J70 — Lung diseases due to external agents (J60-J70) (via C34.-), J61 — Pneumoconiosis due to asbestos and other mineral fibers (via C34.-), J62 — Pneumoconiosis due to dust containing silica (via C34.-), J63 — Pneumoconiosis due to other inorganic dusts (via C34.-), J64 — Unspecified pneumoconiosis (via C34.-), J65 — Pneumoconiosis associated with tuberculosis (via C34.-), J66 — Airway disease due to specific organic dust (via C34.-), J67 — Hypersensitivity pneumonitis due to organic dust (via C34.-), J68 — Respiratory conditions due to inhalation of chemicals, gases, fumes and vapors (via C34.-), J69 — Pneumonitis due to solids and liquids (via C34.-), J70 — Respiratory conditions due to other external agents (via C34.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 1 Code First instruction: J93.12 — Secondary spontaneous pneumothorax (via C34.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

Referenced by 5 Same-site neoplasm codes: C78.0 — Secondary malignant neoplasm of lungCompare C34.9 vs C78.0 →, D02.2 — Carcinoma in situ of bronchus and lungCompare C34.9 vs D02.2 →, D14.3 — Benign neoplasm of bronchus and lungCompare C34.9 vs D14.3 →, D38.1 — Neoplasm of uncertain behavior of trachea, bronchus and lungCompare C34.9 vs D38.1 →, D49.1 — Neoplasm of unspecified behavior of respiratory systemCompare C34.9 vs D49.1 →.

These codes represent related neoplasm behaviors affecting the same anatomic site.

Referenced by 5 Screening & history codes: Z80.1 — Family history of malignant neoplasm of trachea, bronchus and lungCompare C34.9 vs Z80.1 →, Z85.1 — Personal history of malignant neoplasm of trachea, bronchus and lungCompare C34.9 vs Z85.1 →, Z85.11 — Personal history of malignant neoplasm of bronchus and lungCompare C34.9 vs Z85.11 →, Z85.110 — Personal history of malignant carcinoid tumor of bronchus and lungCompare C34.9 vs Z85.110 →, Z85.118 — Personal history of other malignant neoplasm of bronchus and lungCompare C34.9 vs Z85.118 →.

These codes represent screening tests and history codes that refer to this active disease condition.

Contextual Map

Every relationship of C34.9 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run C34.9 with these 9 related codes in Claim Check

Hierarchy

Same site

Referenced by Excludes2 notes (12)

Referenced by Code First instructions

Referenced by Same-site neoplasm codes

Referenced by Screening & history codes MedCoder-derived

Neoplasm sites

  • Neoplasm, neoplastic, bronchiogenic, bronchogenic (lung) — Neoplasm, neoplastic, bronchiogenic, bronchogenic (lung) — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, bronchiogenic, bronchogenic (lung) (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, bronchiole — Neoplasm, neoplastic, bronchiole — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, bronchiole (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, bronchus — Neoplasm, neoplastic, bronchus — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, bronchus (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, lung — Neoplasm, neoplastic, lung — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, lung (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, lung, lobe NEC — Neoplasm, neoplastic, lung, lobe NEC — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, lung, lobe NEC (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, pulmonary — Neoplasm, neoplastic, pulmonary — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, pulmonary (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027
  • Neoplasm, neoplastic, subpleural — Neoplasm, neoplastic, subpleural — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, subpleural (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027

Nearest codes (21)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Neoplasm Table Sites (7)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Anatomical sites from the official ICD-10-CM Table of Neoplasms that map to this code, with the matching behavior column.

  • Neoplasm, neoplastic, bronchiogenic, bronchogenic (lung) — Malignant, Primary
  • Neoplasm, neoplastic, bronchiole — Malignant, Primary
  • Neoplasm, neoplastic, bronchus — Malignant, Primary
  • Neoplasm, neoplastic, lung — Malignant, Primary
  • Neoplasm, neoplastic, lung, lobe NEC — Malignant, Primary
  • Neoplasm, neoplastic, pulmonary — Malignant, Primary
  • Neoplasm, neoplastic, subpleural — Malignant, Primary

Common coding questions

MedCoder editorial

Can C34.9 be billed directly?

No. C34.9 (Malignant neoplasm of unspecified part of bronchus or lung) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "C34.9 — Malignant neoplasm of unspecified part of bronchus or lung." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/c34.9-malignant-neoplasm-of-unspecified-part-of-bronchus-or-lung

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Malignant neoplasm of unspecified part of bronchus or lung

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to C34.9 in its code family, with their registry titles.

View all codes in the C34 family