HCPCS G9424: Specimen Other Than Lung or NSCLC‑NOS - OpenPayer

Summary & Overview

HCPCS G9424: Specimen Other Than Lung or NSCLC‑NOS

HCPCS Level II code G9424 identifies specimens obtained from a site other than the anatomic lung or specimens classified as non–small cell lung cancer, not otherwise specified (NSCLC‑NOS). The code is relevant for pathology reporting and claims adjudication when tumor origin or classification differs from primary lung site documentation. Nationally, accurate use of G9424 affects diagnostic coding consistency, cancer registry capture, and billing for pathology services tied to thoracic oncology care.

Key payers included in the analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find information on the clinical context for using G9424, typical sites of service where the code appears, and common operational considerations for claims processing. The publication also outlines benchmarking and policy-relevant topics for payers and providers, such as coding clarity around specimen site and NSCLC classification, and implications for reimbursement workflows and quality measurement.

The piece serves clinicians, coding staff, and revenue cycle professionals seeking concise guidance on when G9424 applies, what operational settings typically bill it, and what documentation elements are necessary to support claim submission. Data not available in the input is noted where applicable.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicareG9424HCPCS Level IIpathologylung cancerspecimen classificationNSCLConcology codingclaims processinghospital outpatientlaboratory

Billing Code Overview

HCPCS Level II code G9424 denotes a specimen collected from a site other than the anatomic location of the lung, or a specimen classified as non–small cell lung cancer not otherwise specified (nsclc-nos).

Service type: Pathology / specimen collection and classification related to lung cancer diagnosis.
Typical site of service: Hospital outpatient department, ambulatory surgical center, pathology laboratory, or other settings where tumor specimens are processed and classified.

Clinical & Coding Specifications

Clinical Context

A patient with a suspected or confirmed non–small cell lung cancer (NSCLC) presents for tissue-based diagnostic testing where the specimen submitted for pathology/molecular analysis is from a site other than the anatomic lung (for example, a lymph node biopsy, pleural fluid cell block, soft tissue metastasis, or a specimen labeled as NSCLC–NOS). The clinical workflow typically begins with imaging (CT, PET/CT) identifying a suspicious extracavitary or nonpulmonary lesion. Interventional radiology or surgical teams obtain the specimen via core needle biopsy, excisional biopsy, thoracentesis with cell block, or endoscopic sampling. The specimen is sent to surgical pathology for histologic classification and ancillary testing (immunohistochemistry, molecular profiling). Billing uses HCPCS Level II code G9424 to indicate that the specimen site is other than the anatomic location of the lung, or that the specimen is classified as NSCLC–NOS, which informs payors and laboratories of the anatomic origin and potential need for site-specific testing algorithms. Typical site of service: hospital outpatient department, ambulatory surgery center, interventional radiology suite, or pathology/laboratory service. Typical patient scenario: an adult with a suspected metastatic focus (e.g., supraclavicular node) sampled to confirm NSCLC and to obtain tissue for PD-L1 and molecular testing prior to systemic therapy selection.

Coding Specifications

Below are the most clinically relevant modifiers for use with services related to G9424 and when they apply.

Modifier	Description	When to Use

HCPCS G8650: Knee Impairment Residual Score Not Measured

HCPCS-G0472-HEPATITIS-C-ANTIBODY-SCREENING-HIGH-RISK

HCPCS G0472: Hepatitis C Antibody Screening for High-Risk Individuals

HCPCS-G9298-VENOUS-THROMBOEMBOLIC-CARDIOVASCULAR-RISK-EVALUATION-PREOP

HCPCS G9298: Preoperative Venous Thromboembolic and Cardiovascular Risk Evaluation

HCPCS-G9730-PATIENT-REFUSED-TO-PARTICIPATE

HCPCS Level II G9730: Patient Refused to Participate

HCPCS-G9310-UNPLANNED-30-DAY-READMISSION

HCPCS G9310: Unplanned Hospital Readmission within 30 Days

HCPCS-G0455-FECAL-MICROBIOTA-INSTILLATION-PREPARATION

HCPCS G0455: Preparation and Instillation of Fecal Microbiota

HCPCS-G9967-CHILDREN-NOT-SCREENED-DEVELOPMENTAL-RISK

HCPCS G9967: Children Not Screened for Developmental/Behavioral Risk

HCPCS-G9405-POST-DISCHARGE-FOLLOW-UP-WITHIN-7-DAYS

HCPCS G9405: Post-Discharge Follow-Up Within 7 Days

HCPCS-G4009-HOSPITALISTS-MIPS-SPECIALTY-SET

HCPCS G4009: Hospitalists MIPS Specialty Set

HCPCS-G9907-TOBACCO-CESSATION-NO-INTERVENTION-MEDICAL-REASON

HCPCS G9907: Documentation of Medical Reason for No Tobacco Cessation Intervention

Showing 1–10 of 1996

Taxonomy Code	Specialty	Notes
207R00000X	Radiology — Diagnostic	Interventional radiologists commonly perform image-guided biopsies of nonpulmonary metastatic sites.
208000000X	Surgery — General	General surgeons perform excisional biopsies of accessible soft tissue or nodal sites.
2084P0800X	Thoracic Surgery	Thoracic surgeons may obtain mediastinal or pleural specimens when indicated.
207L00000X	Pathology	Pathologists perform tissue processing, histologic classification, and ancillary testing.
363A00000X	Pulmonary Disease	Pulmonologists perform endobronchial or transthoracic sampling and coordinate lung cancer diagnosis and staging.

Related Diagnoses

Typical diagnoses associated with a specimen labeled as a nonpulmonary site or NSCLC–NOS.

ICD-10 Code	Description	Clinical Relevance
`C34.90`	Malignant neoplasm of unspecified part of unspecified bronchus or lung	Used when lung primary is suspected but specimen is from a nonpulmonary site and lung origin remains probable.
`C78.2`	Secondary malignant neoplasm of lung	Relevant when a nonpulmonary specimen is evaluated to determine whether metastasis to a nonlung site originates from lung primary or vice versa.
`C77.0`	Secondary and unspecified malignant neoplasm of lymph nodes of head, face and neck	Frequently used when a cervical or supraclavicular node is biopsied to confirm NSCLC.
`R91.8`	Other nonspecific abnormal findings of lung field	May be used in the diagnostic workup when imaging shows suspicious pulmonary lesions but tissue comes from another site.
`R09.9`	Respiratory abnormality, unspecified	May be used as an interim symptom code when the definitive primary site is not yet established and a nonpulmonary specimen is submitted.

Related CPT Codes

Common CPT codes performed alongside or in support of a specimen from a nonpulmonary site sampled for NSCLC diagnosis.

CPT Code	Description	Relationship to This Procedure
`10022`	Fine needle aspiration without imaging guidance	May be used when a palpable nonpulmonary mass or node is sampled without image guidance prior to pathology coding with `G9424`.
`10005`	Fine needle aspiration with imaging guidance for a non-superficial lesion; first lesion	Used when CT/US-guided fine needle aspiration is performed on an extracpulmonary lesion that becomes the specimen described by `G9424`.
`32421`	Thoracentesis, therapeutic (for pleural effusion) including obtaining sample	Used when pleural fluid is obtained and processed as a cell block representing a nonpulmonary specimen for analysis under `G9424`.
`38500`	Biopsy or excision of lymph node (open)	Used when an excisional lymph node biopsy provides the specimen that is not from the anatomic lung and is reported with `G9424`.
`38999`	Unlisted procedure, hemic/lymphatic system	May be used for atypical lymphatic or nodal procedures not described by a specific CPT when tissue is submitted and coded with `G9424`.

`22`	Increased procedural services	Use when work required to process/interpret an atypically complex specimen or when extensive pathology work-up and reporting exceed typical service.
`23`	Unusual anesthesia	Use if unusual anesthesia is required for biopsy of an extracpulmonary site associated with this service.
`52`	Reduced services	Use when the procedure was partially reduced or not completed but still billed.
`53`	Discontinued procedure	Use when the biopsy or specimen collection was started but terminated due to complications or patient condition.
`54`	Surgical care only	Use when billing only for the surgical portion of care and another provider bills postoperative care.
`55`	Postoperative management only	Use when billing only for postoperative care related to the biopsy or excision.
`56`	Preoperative management only	Use when billing only for preoperative evaluation related to the specimen acquisition.
`62`	Two surgeons	Use when two surgeons of different specialties are required to obtain the specimen.
`AS`	Ambulatory surgical center facility	Use to indicate the service was performed in an ASC when reporting facility charges.
`CO`	Workers' compensation	Use when the claim is related to workers’ compensation.
`CQ`	Service furnished by a CRNA without an anesthesiologist	Use when a certified registered nurse anesthetist provides anesthesia for the specimen acquisition.
`FX`	Primary surgeon no longer performs surgical assist	Use when the primary surgeon no longer performs assistant-at-surgery duties and an assistant is used for the biopsy procedure.
`FY`	Primary surgeon no longer personally performs the procedure	Use when the primary surgeon delegates parts of the surgical procedure associated with specimen acquisition.
`QK`	Medical direction of two, three, or four concurrent anesthesia procedures	Use when medical direction is provided during anesthesia for multiple concurrent procedures.
`QX`	CRNA service with modifier `QK` omitted	Use to indicate the CRNA service when required by payor rules.

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